bug fix with missing early return statements fix #112

* set log limit to 100K in browser

.github/workflows/closeinactive.yml

@@ -13,11 +13,11 @@ jobs:
     steps:
       - uses: actions/stale@v9
         with:
-          days-before-issue-stale: 30
+          days-before-issue-stale: 14
           days-before-issue-close: 14
           stale-issue-label: "stale"
-          stale-issue-message: "This issue is stale because it has been open for 30 days with no activity."
-          close-issue-message: "This issue was closed because it has been inactive for 14 days since being marked as stale."
+          stale-issue-message: "This issue is stale because it has been open for 2 weeks with no activity."
+          close-issue-message: "This issue was closed because it has been inactive for 2 weeks since being marked as stale."
           days-before-pr-stale: -1
           days-before-pr-close: -1
-          repo-token: ${{ secrets.GITHUB_TOKEN }}
+          repo-token: ${{ secrets.GITHUB_TOKEN }}

.goreleaser.yaml

@@ -15,4 +15,16 @@ builds:
       - goos: freebsd
         goarch: arm64
       - goos: windows
-        goarch: arm64
+        goarch: arm64
+
+# use zip format for windows
+archives:
+  - id: default
+    format: tar.gz
+    name_template: "{{ .ProjectName }}_{{ .Version }}_{{ .Os }}_{{ .Arch }}"
+    builds_info:
+      group: root
+      owner: root
+    format_overrides:
+      - goos: windows
+        format: zip

README.md

@@ -1,4 +1,7 @@
-![llama-swap header image](header.jpeg)
+![llama-swap header image](header2.png)
+![GitHub Downloads (all assets, all releases)](https://img.shields.io/github/downloads/mostlygeek/llama-swap/total)
+![GitHub Actions Workflow Status](https://img.shields.io/github/actions/workflow/status/mostlygeek/llama-swap/go-ci.yml)
+![GitHub Repo stars](https://img.shields.io/github/stars/mostlygeek/llama-swap)
 
 # llama-swap
 
@@ -23,7 +26,7 @@ Written in golang, it is very easy to install (single binary with no dependancie
   - `/upstream/:model_id` - direct access to upstream HTTP server ([demo](https://github.com/mostlygeek/llama-swap/pull/31))
   - `/unload` - manually unload running models ([#58](https://github.com/mostlygeek/llama-swap/issues/58))
   - `/running` - list currently running models ([#61](https://github.com/mostlygeek/llama-swap/issues/61))
-- ✅ Run multiple models at once with `profiles` ([docs](https://github.com/mostlygeek/llama-swap/issues/53#issuecomment-2660761741))
+- ✅ Run multiple models at once with `Groups` ([#107](https://github.com/mostlygeek/llama-swap/issues/107))
 - ✅ Automatic unloading of models after timeout by setting a `ttl`
 - ✅ Use any local OpenAI compatible server (llama.cpp, vllm, tabbyAPI, etc)
 - ✅ Docker and Podman support
@@ -33,7 +36,7 @@ Written in golang, it is very easy to install (single binary with no dependancie
 
 When a request is made to an OpenAI compatible endpoint, lama-swap will extract the `model` value and load the appropriate server configuration to serve it. If the wrong upstream server is running, it will be replaced with the correct one. This is where the "swap" part comes in. The upstream server is automatically swapped to the correct one to serve the request.
 
-In the most basic configuration llama-swap handles one model at a time. For more advanced use cases, the `profiles` feature can load multiple models at the same time. You have complete control over how your system resources are used.
+In the most basic configuration llama-swap handles one model at a time. For more advanced use cases, the `groups` feature allows multiple models to be loaded at the same time. You have complete control over how your system resources are used.
 
 ## config.yaml
 
@@ -64,8 +67,8 @@ models:
 # Default (and minimum) is 15 seconds
 healthCheckTimeout: 60
 
-# Write HTTP logs (useful for troubleshooting), defaults to false
-logRequests: true
+# Valid log levels: debug, info (default), warn, error
+logLevel: info
 
 # define valid model values and the upstream server start
 models:
@@ -117,16 +120,58 @@ models:
       ghcr.io/ggerganov/llama.cpp:server
       --model '/models/Qwen2.5-Coder-0.5B-Instruct-Q4_K_M.gguf'
 
-# profiles eliminates swapping by running multiple models at the same time
+# Groups provide advanced controls over model swapping behaviour. Using groups
+# some models can be kept loaded indefinitely, while others are swapped out.
 #
 # Tips:
-#  - each model must be listening on a unique address and port
-#  - the model name is in this format: "profile_name:model", like "coding:qwen"
-#  - the profile will load and unload all models in the profile at the same time
-profiles:
-  coding:
-    - "llama"
-    - "qwen-unlisted"
+#
+#  - models must be defined above in the Models section
+#  - a model can only be a member of one group
+#  - group behaviour is controlled via the `swap`, `exclusive` and `persistent` fields
+#  - see issue #109 for details
+#
+# NOTE: the example below uses model names that are not defined above for demonstration purposes
+groups:
+  # group1 is the default behaviour of llama-swap where only one model is allowed
+  # to run a time across the whole llama-swap instance
+  "group1":
+    # swap controls the model swapping behaviour in within the group
+    # - true : only one model is allowed to run at a time
+    # - false: all models can run together, no swapping
+    swap: true
+
+    # exclusive controls how the group affects other groups
+    # - true: causes all other groups to unload their models when this group runs a model
+    # - false: does not affect other groups
+    exclusive: true
+
+    # members references the models defined above
+    members:
+      - "llama"
+      - "qwen-unlisted"
+
+  # models in this group are never unloaded
+  "group2":
+    swap: false
+    exclusive: false
+    members:
+      - "docker-llama"
+      # (not defined above, here for example)
+      - "modelA"
+      - "modelB"
+
+  "forever":
+    # setting persistent to true causes the group to never be affected by the swapping behaviour of
+    # other groups. It is a shortcut to keeping some models always loaded.
+    persistent: true
+
+    # set swap/exclusive to false to prevent swapping inside the group and effect on other groups
+    swap: false
+    exclusive: false
+    members:
+      - "forever-modelA"
+      - "forever-modelB"
+      - "forever-modelc"
 ```
 
 ### Use Case Examples
@@ -216,9 +261,15 @@ Of course, CLI access is also supported:
 # sends up to the last 10KB of logs
 curl http://host/logs'
 
-# streams logs
+# streams combined logs
 curl -Ns 'http://host/logs/stream'
 
+# just llama-swap's logs
+curl -Ns 'http://host/logs/stream/proxy'
+
+# just upstream's logs
+curl -Ns 'http://host/logs/stream/upstream'
+
 # stream and filter logs with linux pipes
 curl -Ns http://host/logs/stream | grep 'eval time'
 
@@ -260,8 +311,4 @@ WantedBy=multi-user.target
 
 ## Star History
 
-<picture>
-   <source media="(prefers-color-scheme: dark)" srcset="https://api.star-history.com/svg?repos=mostlygeek/llama-swap&type=Date&theme=dark" />
-   <source media="(prefers-color-scheme: light)" srcset="https://api.star-history.com/svg?repos=mostlygeek/llama-swap&type=Date" />
-   <img alt="Star History Chart" src="https://api.star-history.com/svg?repos=mostlygeek/llama-swap&type=Date" />
-</picture>
+[![Star History Chart](https://api.star-history.com/svg?repos=mostlygeek/llama-swap&type=Date)](https://www.star-history.com/#mostlygeek/llama-swap&Date)

config.example.yaml

@@ -1,9 +1,9 @@
 # Seconds to wait for llama.cpp to be available to serve requests
 # Default (and minimum): 15 seconds
-healthCheckTimeout: 15
+healthCheckTimeout: 90
 
-# Log HTTP requests helpful for troubleshoot, defaults to False
-logRequests: true
+# valid log levels: debug, info (default), warn, error
+logLevel: debug
 
 models:
   "llama":

examples/aider-qwq-coder/README.md

@@ -0,0 +1,153 @@
+# aider, QwQ, Qwen-Coder 2.5 and llama-swap
+
+This guide show how to use aider and llama-swap to get a 100% local coding co-pilot setup. The focus is on the trickest part which is configuring aider, llama-swap and llama-server to work together.
+
+## Here's what you you need:
+
+- aider - [installation docs](https://aider.chat/docs/install.html)
+- llama-server - [download latest release](https://github.com/ggml-org/llama.cpp/releases)
+- llama-swap - [download latest release](https://github.com/mostlygeek/llama-swap/releases)
+- [QwQ 32B](https://huggingface.co/bartowski/Qwen_QwQ-32B-GGUF) and [Qwen Coder 2.5 32B](https://huggingface.co/bartowski/Qwen2.5-Coder-32B-Instruct-GGUF) models
+- 24GB VRAM video card
+
+## Running aider
+
+The goal is getting this command line to work:
+
+```sh
+aider --architect \
+    --no-show-model-warnings \
+    --model openai/QwQ \
+    --editor-model openai/qwen-coder-32B \
+    --model-settings-file aider.model.settings.yml \
+    --openai-api-key "sk-na" \
+    --openai-api-base "http://10.0.1.24:8080/v1" \
+```
+
+Set `--openai-api-base` to the IP and port where your llama-swap is running.
+
+## Create an aider model settings file
+
+```yaml
+# aider.model.settings.yml
+
+#
+# !!! important: model names must match llama-swap configuration names !!!
+#
+
+- name: "openai/QwQ"
+  edit_format: diff
+  extra_params:
+    max_tokens: 16384
+    top_p: 0.95
+    top_k: 40
+    presence_penalty: 0.1
+    repetition_penalty: 1
+    num_ctx: 16384
+  use_temperature: 0.6
+  reasoning_tag: think
+  weak_model_name: "openai/qwen-coder-32B"
+  editor_model_name: "openai/qwen-coder-32B"
+
+- name: "openai/qwen-coder-32B"
+  edit_format: diff
+  extra_params:
+    max_tokens: 16384
+    top_p: 0.8
+    top_k: 20
+    repetition_penalty: 1.05
+  use_temperature: 0.6
+  reasoning_tag: think
+  editor_edit_format: editor-diff
+  editor_model_name: "openai/qwen-coder-32B"
+```
+
+## llama-swap configuration
+
+```yaml
+# config.yaml
+
+# The parameters are tweaked to fit model+context into 24GB VRAM GPUs
+models:
+  "qwen-coder-32B":
+    proxy: "http://127.0.0.1:8999"
+    cmd: >
+      /path/to/llama-server
+      --host 127.0.0.1 --port 8999 --flash-attn --slots
+      --ctx-size 16000
+      --cache-type-k q8_0 --cache-type-v q8_0
+       -ngl 99
+      --model /path/to/Qwen2.5-Coder-32B-Instruct-Q4_K_M.gguf
+
+  "QwQ":
+    proxy: "http://127.0.0.1:9503"
+    cmd: >
+      /path/to/llama-server
+      --host 127.0.0.1 --port 9503 --flash-attn --metrics--slots
+      --cache-type-k q8_0 --cache-type-v q8_0
+      --ctx-size 32000
+      --samplers "top_k;top_p;min_p;temperature;dry;typ_p;xtc"
+      --temp 0.6 --repeat-penalty 1.1 --dry-multiplier 0.5
+      --min-p 0.01 --top-k 40 --top-p 0.95
+      -ngl 99
+      --model /mnt/nvme/models/bartowski/Qwen_QwQ-32B-Q4_K_M.gguf
+```
+
+## Advanced, Dual GPU Configuration
+
+If you have _dual 24GB GPUs_ you can use llama-swap profiles to avoid swapping between QwQ and Qwen Coder.
+
+In llama-swap's configuration file:
+
+1. add a `profiles` section with `aider` as the profile name
+2. using the `env` field to specify the GPU IDs for each model
+
+```yaml
+# config.yaml
+
+# Add a profile for aider
+profiles:
+  aider:
+    - qwen-coder-32B
+    - QwQ
+
+models:
+  "qwen-coder-32B":
+    # manually set the GPU to run on
+    env:
+      - "CUDA_VISIBLE_DEVICES=0"
+    proxy: "http://127.0.0.1:8999"
+    cmd: /path/to/llama-server ...
+
+  "QwQ":
+    # manually set the GPU to run on
+    env:
+      - "CUDA_VISIBLE_DEVICES=1"
+    proxy: "http://127.0.0.1:9503"
+    cmd: /path/to/llama-server ...
+```
+
+Append the profile tag, `aider:`, to the model names in the model settings file
+
+```yaml
+# aider.model.settings.yml
+- name: "openai/aider:QwQ"
+  weak_model_name: "openai/aider:qwen-coder-32B-aider"
+  editor_model_name: "openai/aider:qwen-coder-32B-aider"
+
+- name: "openai/aider:qwen-coder-32B"
+  editor_model_name: "openai/aider:qwen-coder-32B-aider"
+```
+
+Run aider with:
+
+```sh
+$ aider --architect \
+    --no-show-model-warnings \
+    --model openai/aider:QwQ \
+    --editor-model openai/aider:qwen-coder-32B \
+    --config aider.conf.yml \
+    --model-settings-file aider.model.settings.yml
+    --openai-api-key "sk-na" \
+    --openai-api-base "http://10.0.1.24:8080/v1"
+```

examples/aider-qwq-coder/aider.model.settings.dualgpu.yml

@@ -0,0 +1,28 @@
+# this makes use of llama-swap's profile feature to
+# keep the architect and editor models in VRAM on different GPUs
+
+- name: "openai/aider:QwQ"
+  edit_format: diff
+  extra_params:
+    max_tokens: 16384
+    top_p: 0.95
+    top_k: 40
+    presence_penalty: 0.1
+    repetition_penalty: 1
+    num_ctx: 16384
+  use_temperature: 0.6
+  reasoning_tag: think
+  weak_model_name: "openai/aider:qwen-coder-32B"
+  editor_model_name: "openai/aider:qwen-coder-32B"
+
+- name: "openai/aider:qwen-coder-32B"
+  edit_format: diff
+  extra_params:
+    max_tokens: 16384
+    top_p: 0.8
+    top_k: 20
+    repetition_penalty: 1.05
+  use_temperature: 0.6
+  reasoning_tag: think
+  editor_edit_format: editor-diff
+  editor_model_name: "openai/aider:qwen-coder-32B"

examples/aider-qwq-coder/aider.model.settings.yml

@@ -0,0 +1,26 @@
+- name: "openai/QwQ"
+  edit_format: diff
+  extra_params:
+    max_tokens: 16384
+    top_p: 0.95
+    top_k: 40
+    presence_penalty: 0.1
+    repetition_penalty: 1
+    num_ctx: 16384
+  use_temperature: 0.6
+  reasoning_tag: think
+  weak_model_name: "openai/qwen-coder-32B"
+  editor_model_name: "openai/qwen-coder-32B"
+
+- name: "openai/qwen-coder-32B"
+  edit_format: diff
+  extra_params:
+    max_tokens: 16384
+    top_p: 0.8
+    top_k: 20
+    repetition_penalty: 1.05
+  use_temperature: 0.6
+  reasoning_tag: think
+  editor_edit_format: editor-diff
+  editor_model_name: "openai/qwen-coder-32B"
+

examples/aider-qwq-coder/llama-swap.yaml

@@ -0,0 +1,49 @@
+healthCheckTimeout: 300
+logLevel: debug
+
+profiles:
+    aider:
+      - qwen-coder-32B
+      - QwQ
+
+models:
+  "qwen-coder-32B":
+    env:
+      - "CUDA_VISIBLE_DEVICES=0"
+    aliases:
+      - coder
+    proxy: "http://127.0.0.1:8999"
+
+    # set appropriate paths for your environment
+    cmd: >
+      /path/to/llama-server
+      --host 127.0.0.1 --port 8999 --flash-attn --slots
+      --ctx-size 16000
+      --ctx-size-draft 16000
+      --model /path/to/Qwen2.5-Coder-32B-Instruct-Q4_K_M.gguf
+      --model-draft /path/to/Qwen2.5-Coder-1.5B-Instruct-Q8_0.gguf
+      -ngl 99 -ngld 99
+      --draft-max 16 --draft-min 4 --draft-p-min 0.4
+      --cache-type-k q8_0 --cache-type-v q8_0
+  "QwQ":
+    env:
+      - "CUDA_VISIBLE_DEVICES=1"
+    proxy: "http://127.0.0.1:9503"
+
+    # set appropriate paths for your environment
+    cmd: >
+      /path/to/llama-server
+      --host 127.0.0.1 --port 9503
+      --flash-attn --metrics
+      --slots
+      --model /path/to/Qwen_QwQ-32B-Q4_K_M.gguf
+      --cache-type-k q8_0 --cache-type-v q8_0
+      --ctx-size 32000
+      --samplers "top_k;top_p;min_p;temperature;dry;typ_p;xtc"
+      --temp 0.6
+      --repeat-penalty 1.1
+      --dry-multiplier 0.5
+      --min-p 0.01
+      --top-k 40
+      --top-p 0.95
+      -ngl 99 -ngld 99

go.mod

@@ -37,7 +37,7 @@ require (
 	github.com/ugorji/go/codec v1.2.12 // indirect
 	golang.org/x/arch v0.8.0 // indirect
 	golang.org/x/crypto v0.36.0 // indirect
-	golang.org/x/net v0.37.0 // indirect
+	golang.org/x/net v0.38.0 // indirect
 	golang.org/x/sys v0.31.0 // indirect
 	golang.org/x/text v0.23.0 // indirect
 	google.golang.org/protobuf v1.34.1 // indirect

go.sum

@@ -86,6 +86,8 @@ golang.org/x/net v0.33.0 h1:74SYHlV8BIgHIFC/LrYkOGIwL19eTYXQ5wc6TBuO36I=
 golang.org/x/net v0.33.0/go.mod h1:HXLR5J+9DxmrqMwG9qjGCxZ+zKXxBru04zlTvWlWuN4=
 golang.org/x/net v0.37.0 h1:1zLorHbz+LYj7MQlSf1+2tPIIgibq2eL5xkrGk6f+2c=
 golang.org/x/net v0.37.0/go.mod h1:ivrbrMbzFq5J41QOQh0siUuly180yBYtLp+CKbEaFx8=
+golang.org/x/net v0.38.0 h1:vRMAPTMaeGqVhG5QyLJHqNDwecKTomGeqbnfZyKlBI8=
+golang.org/x/net v0.38.0/go.mod h1:ivrbrMbzFq5J41QOQh0siUuly180yBYtLp+CKbEaFx8=
 golang.org/x/sys v0.5.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.20.0 h1:Od9JTbYCk261bKm4M/mw7AklTlFYIa0bIp9BgSm1S8Y=

llama-swap.go

@@ -34,6 +34,10 @@ func main() {
 		os.Exit(1)
 	}
 
+	if len(config.Profiles) > 0 {
+		fmt.Println("WARNING: Profile functionality has been removed in favor of Groups. See the README for more information.")
+	}
+
 	if mode := os.Getenv("GIN_MODE"); mode != "" {
 		gin.SetMode(mode)
 	} else {

proxy/config.go

@@ -3,12 +3,15 @@ package proxy
 import (
 	"fmt"
 	"os"
+	"sort"
 	"strings"
 
 	"github.com/google/shlex"
 	"gopkg.in/yaml.v3"
 )
 
+const DEFAULT_GROUP_ID = "(default)"
+
 type ModelConfig struct {
 	Cmd           string   `yaml:"cmd"`
 	Proxy         string   `yaml:"proxy"`
@@ -24,11 +27,38 @@ func (m *ModelConfig) SanitizedCommand() ([]string, error) {
 	return SanitizeCommand(m.Cmd)
 }
 
+type GroupConfig struct {
+	Swap       bool     `yaml:"swap"`
+	Exclusive  bool     `yaml:"exclusive"`
+	Persistent bool     `yaml:"persistent"`
+	Members    []string `yaml:"members"`
+}
+
+// set default values for GroupConfig
+func (c *GroupConfig) UnmarshalYAML(unmarshal func(interface{}) error) error {
+	type rawGroupConfig GroupConfig
+	defaults := rawGroupConfig{
+		Swap:       true,
+		Exclusive:  true,
+		Persistent: false,
+		Members:    []string{},
+	}
+
+	if err := unmarshal(&defaults); err != nil {
+		return err
+	}
+
+	*c = GroupConfig(defaults)
+	return nil
+}
+
 type Config struct {
 	HealthCheckTimeout int                    `yaml:"healthCheckTimeout"`
 	LogRequests        bool                   `yaml:"logRequests"`
-	Models             map[string]ModelConfig `yaml:"models"`
+	LogLevel           string                 `yaml:"logLevel"`
+	Models             map[string]ModelConfig `yaml:"models"` /* key is model ID */
 	Profiles           map[string][]string    `yaml:"profiles"`
+	Groups             map[string]GroupConfig `yaml:"groups"` /* key is group ID */
 
 	// map aliases to actual model IDs
 	aliases map[string]string
@@ -52,16 +82,16 @@ func (c *Config) FindConfig(modelName string) (ModelConfig, string, bool) {
 	}
 }
 
-func LoadConfig(path string) (*Config, error) {
+func LoadConfig(path string) (Config, error) {
 	data, err := os.ReadFile(path)
 	if err != nil {
-		return nil, err
+		return Config{}, err
 	}
 
 	var config Config
 	err = yaml.Unmarshal(data, &config)
 	if err != nil {
-		return nil, err
+		return Config{}, err
 	}
 
 	if config.HealthCheckTimeout < 15 {
@@ -76,7 +106,72 @@ func LoadConfig(path string) (*Config, error) {
 		}
 	}
 
-	return &config, nil
+	config = AddDefaultGroupToConfig(config)
+	// check that members are all unique in the groups
+	memberUsage := make(map[string]string) // maps member to group it appears in
+	for groupID, groupConfig := range config.Groups {
+		prevSet := make(map[string]bool)
+		for _, member := range groupConfig.Members {
+			// Check for duplicates within this group
+			if _, found := prevSet[member]; found {
+				return Config{}, fmt.Errorf("duplicate model member %s found in group: %s", member, groupID)
+			}
+			prevSet[member] = true
+
+			// Check if member is used in another group
+			if existingGroup, exists := memberUsage[member]; exists {
+				return Config{}, fmt.Errorf("model member %s is used in multiple groups: %s and %s", member, existingGroup, groupID)
+			}
+			memberUsage[member] = groupID
+		}
+	}
+
+	return config, nil
+}
+
+// rewrites the yaml to include a default group with any orphaned models
+func AddDefaultGroupToConfig(config Config) Config {
+
+	if config.Groups == nil {
+		config.Groups = make(map[string]GroupConfig)
+	}
+
+	defaultGroup := GroupConfig{
+		Swap:      true,
+		Exclusive: true,
+		Members:   []string{},
+	}
+	// if groups is empty, create a default group and put
+	// all models into it
+	if len(config.Groups) == 0 {
+		for modelName := range config.Models {
+			defaultGroup.Members = append(defaultGroup.Members, modelName)
+		}
+	} else {
+		// iterate over existing group members and add non-grouped models into the default group
+		for modelName, _ := range config.Models {
+			foundModel := false
+		found:
+			// search for the model in existing groups
+			for _, groupConfig := range config.Groups {
+				for _, member := range groupConfig.Members {
+					if member == modelName {
+						foundModel = true
+						break found
+					}
+				}
+			}
+
+			if !foundModel {
+				defaultGroup.Members = append(defaultGroup.Members, modelName)
+			}
+		}
+	}
+
+	sort.Strings(defaultGroup.Members) // make consistent ordering for testing
+	config.Groups[DEFAULT_GROUP_ID] = defaultGroup
+
+	return config
 }
 
 func SanitizeCommand(cmdStr string) ([]string, error) {

proxy/config_test.go

@@ -35,11 +35,31 @@ models:
     aliases:
       - "m2"
     checkEndpoint: "/"
+  model3:
+    cmd: path/to/cmd --arg1 one
+    proxy: "http://localhost:8081"
+    aliases:
+      - "mthree"
+    checkEndpoint: "/"
+  model4:
+    cmd: path/to/cmd --arg1 one
+    checkEndpoint: "/"
+
 healthCheckTimeout: 15
 profiles:
   test:
     - model1
     - model2
+groups:
+  group1:
+    swap: true
+    exclusive: false
+    members: ["model2"]
+  forever:
+    exclusive: false
+    persistent: true
+    members:
+      - "model4"
 `
 
 	if err := os.WriteFile(tempFile, []byte(content), 0644); err != nil {
@@ -52,7 +72,7 @@ profiles:
 		t.Fatalf("Failed to load config: %v", err)
 	}
 
-	expected := &Config{
+	expected := Config{
 		Models: map[string]ModelConfig{
 			"model1": {
 				Cmd:           "path/to/cmd --arg1 one",
@@ -68,6 +88,17 @@ profiles:
 				Env:           nil,
 				CheckEndpoint: "/",
 			},
+			"model3": {
+				Cmd:           "path/to/cmd --arg1 one",
+				Proxy:         "http://localhost:8081",
+				Aliases:       []string{"mthree"},
+				Env:           nil,
+				CheckEndpoint: "/",
+			},
+			"model4": {
+				Cmd:           "path/to/cmd --arg1 one",
+				CheckEndpoint: "/",
+			},
 		},
 		HealthCheckTimeout: 15,
 		Profiles: map[string][]string{
@@ -77,6 +108,25 @@ profiles:
 			"m1":        "model1",
 			"model-one": "model1",
 			"m2":        "model2",
+			"mthree":    "model3",
+		},
+		Groups: map[string]GroupConfig{
+			DEFAULT_GROUP_ID: {
+				Swap:      true,
+				Exclusive: true,
+				Members:   []string{"model1", "model3"},
+			},
+			"group1": {
+				Swap:      true,
+				Exclusive: false,
+				Members:   []string{"model2"},
+			},
+			"forever": {
+				Swap:       true,
+				Exclusive:  false,
+				Persistent: true,
+				Members:    []string{"model4"},
+			},
 		},
 	}
 
@@ -87,6 +137,51 @@ profiles:
 	assert.Equal(t, "model1", realname)
 }
 
+func TestConfig_GroupMemberIsUnique(t *testing.T) {
+	// Create a temporary YAML file for testing
+	tempDir, err := os.MkdirTemp("", "test-config")
+	if err != nil {
+		t.Fatalf("Failed to create temporary directory: %v", err)
+	}
+	defer os.RemoveAll(tempDir)
+
+	tempFile := filepath.Join(tempDir, "config.yaml")
+	content := `
+models:
+  model1:
+    cmd: path/to/cmd --arg1 one
+    proxy: "http://localhost:8080"
+  model2:
+    cmd: path/to/cmd --arg1 one
+    proxy: "http://localhost:8081"
+    checkEndpoint: "/"
+  model3:
+    cmd: path/to/cmd --arg1 one
+    proxy: "http://localhost:8081"
+    checkEndpoint: "/"
+
+healthCheckTimeout: 15
+groups:
+  group1:
+    swap: true
+    exclusive: false
+    members: ["model2"]
+  group2:
+    swap: true
+    exclusive: false
+    members: ["model2"]
+`
+
+	if err := os.WriteFile(tempFile, []byte(content), 0644); err != nil {
+		t.Fatalf("Failed to write temporary file: %v", err)
+	}
+
+	// Load the config and verify
+	_, err = LoadConfig(tempFile)
+	assert.NotNil(t, err)
+
+}
+
 func TestConfig_ModelConfigSanitizedCommand(t *testing.T) {
 	config := &ModelConfig{
 		Cmd: `python model1.py \

proxy/helpers_test.go

@@ -14,6 +14,7 @@ import (
 var (
 	nextTestPort int = 12000
 	portMutex    sync.Mutex
+	testLogger   = NewLogMonitorWriter(os.Stdout)
 )
 
 // Check if the binary exists
@@ -26,6 +27,17 @@ func TestMain(m *testing.M) {
 
 	gin.SetMode(gin.TestMode)
 
+	switch os.Getenv("LOG_LEVEL") {
+	case "debug":
+		testLogger.SetLogLevel(LevelDebug)
+	case "warn":
+		testLogger.SetLogLevel(LevelWarn)
+	case "info":
+		testLogger.SetLogLevel(LevelInfo)
+	default:
+		testLogger.SetLogLevel(LevelWarn)
+	}
+
 	m.Run()
 }
 

proxy/html/logs.html

@@ -12,32 +12,65 @@
             flex-direction: column;
             font-family: "Courier New", Courier, monospace;
         }
-        #log-controls {
-            margin: 0.5em;
+        .log-container {
             display: flex;
-            align-items: center;
-            justify-content: space-between; /* Spaces out elements evenly */
-        }
-        #log-controls input {
-            flex: 1;
-        }
-        #log-controls input:focus {
-           outline: none; /* Ensures no outline is shown when the input is focused */
-        }
-        #log-stream {
             flex: 1;
+            gap: 0.5em;
             margin: 0.5em;
+            min-height: 0;
+        }
+        .log-column {
+            display: flex;
+            flex-direction: column;
+            flex: 1;
+            min-width: 0;
+            transition: flex 0.3s ease;
+        }
+        .log-column.minimized {
+            flex: 0.1;
+            max-width: 50px;
+            border: 1px solid #777;
+            color: green;
+        }
+        .log-controls {
+            display: grid;
+            grid-template-columns: 1fr auto;
+            gap: 0.5em;
+            margin-bottom: 0.5em;
+        }
+        .log-controls input {
+            width: 100%;
+            padding: 4px;
+        }
+        .log-controls input:focus {
+           outline: none;
+        }
+        .log-stream {
+            flex: 1;
             padding: 1em;
             background: #f4f4f4;
             overflow-y: auto;
-            white-space: pre-wrap; /* Ensures line wrapping */
-            word-wrap: break-word; /* Ensures long words wrap */
+            white-space: pre-wrap;
+            word-wrap: break-word;
+            min-height: 0;
         }
 
         .regex-error {
             background-color: #ff0000 !important;
         }
 
+        /* Make headers clickable and show pointer cursor */
+        h2 {
+            cursor: pointer;
+            user-select: none;
+            margin: 0 0 0.5em 0;
+            padding: 0.5em;
+        }
+
+        h2:hover {
+            background-color: rgba(0, 0, 0, 0.05);
+        }
+
         /* Dark mode styles */
         @media (prefers-color-scheme: dark) {
             body {
@@ -45,101 +78,182 @@
                 color: #fff;
             }
 
-            #log-stream {
+            .log-stream {
                 background: #444;
                 color: #fff;
             }
 
-            #log-controls input {
+            .log-controls input {
                 background: #555;
                 color: #fff;
                 border: 1px solid #777;
             }
 
-            #log-controls button {
+            .log-controls button {
                 background: #555;
                 color: #fff;
                 border: 1px solid #777;
             }
+
+            h2:hover {
+                background-color: rgba(255, 255, 255, 0.1);
+            }
+        }
+
+        /* Hide content when minimized */
+        .log-column.minimized .log-controls,
+        .log-column.minimized .log-stream {
+            display: none;
+        }
+
+        .log-column.minimized h2 {
+            writing-mode: vertical-rl;
+            text-orientation: mixed;
+            transform: rotate(180deg);
+            white-space: nowrap;
+            margin: auto;
         }
     </style>
 </head>
 <body>
-    <pre id="log-stream">Waiting for logs...</pre>
-    <div id="log-controls">
-        <input type="text" id="filter-input" placeholder="regex filter">
-        <button id="clear-button">clear</button>
+    <div class="log-container">
+        <div class="log-column">
+            <h2>Proxy Logs</h2>
+            <div class="log-controls">
+                <input type="text" id="proxy-filter-input" placeholder="proxy regex filter">
+                <button id="proxy-clear-button">clear</button>
+            </div>
+            <pre class="log-stream" id="proxy-log-stream">Waiting for proxy logs...</pre>
+        </div>
+        <div class="log-column minimized">
+            <h2>Upstream Logs</h2>
+            <div class="log-controls">
+                <input type="text" id="upstream-filter-input" placeholder="upstream regex filter">
+                <button id="upstream-clear-button">clear</button>
+            </div>
+            <pre class="log-stream" id="upstream-log-stream">Waiting for upstream logs...</pre>
+        </div>
     </div>
     <script>
-        const logStream = document.getElementById('log-stream');
-        const filterInput = document.getElementById('filter-input');
-        var logData = "";
-        let regexFilter = null;
+        class LogStream {
+            constructor(streamElement, filterInput, clearButton, endpoint) {
+                this.streamElement = streamElement;
+                this.filterInput = filterInput;
+                this.clearButton = clearButton;
+                this.endpoint = endpoint;
+                this.logData = "";
+                this.regexFilter = null;
+                this.eventSource = null;
 
-        function setupEventSource() {
-            if (typeof(EventSource) !== "undefined") {
-                const eventSource = new EventSource("/logs/streamSSE");
-
-                eventSource.onmessage = function(event) {
-                    logData += event.data;
-                    render()
-                };
-
-                eventSource.onerror = function(err) {
-                    logData = "EventSource failed: " + err.message;
-                };
-            } else {
-                logData = "SSE Not supported by this browser."
+                this.initialize();
             }
-        }
 
-        // poor-ai's react  ¯\_(ツ)_/¯
-        function render() {
-            if (regexFilter) {
-                const lines = logData.split('\n');
-                const filteredLines = lines.filter(line => {
-                    return regexFilter === null || regexFilter.test(line);
+            initialize() {
+                this.filterInput.addEventListener('input', () => this.updateFilter());
+                this.clearButton.addEventListener('click', () => {
+                    this.filterInput.value = "";
+                    this.regexFilter = null;
+                    this.render();
                 });
-
-                if (filteredLines.length > 0) {
-                    logStream.textContent = filteredLines.join('\n') + '\n';
-                } else {
-                    logStream.textContent = "";
-                }
-            } else {
-                logStream.textContent = logData;
+                this.setupEventSource();
             }
 
-            logStream.scrollTop = logStream.scrollHeight;
-        }
+            setupEventSource() {
+                if (typeof(EventSource) === "undefined") {
+                    this.logData = "SSE Not supported by this browser.";
+                    this.render();
+                    return;
+                }
+
+                const connect = () => {
+                    this.eventSource = new EventSource(this.endpoint);
+
+                    this.eventSource.onmessage = (event) => {
+                        this.logData += event.data;
+                        this.logData = this.logData.slice(-1024 * 100);
+                        this.render();
+                    };
+
+                    this.eventSource.onerror = (err) => {
+                        // Close the current connection
+                        this.eventSource.close();
+
+                        this.logData += "\nConnection lost. Retrying in 5 seconds...\n";
+                        this.render();
+
+                        // Attempt to reconnect after 5 seconds
+                        setTimeout(() => {
+                            this.logData += "Attempting to reconnect...\n";
+                            this.render();
+                            connect();
+                        }, 5000);
+                    };
+                };
+
+                // Initial connection
+                connect();
+            }
+
+            render() {
+                let content = this.logData;
+
+                if (this.regexFilter) {
+                    const lines = content.split('\n');
+                    const filteredLines = lines.filter(line => this.regexFilter.test(line));
+                    content = filteredLines.length > 0 ? filteredLines.join('\n') + '\n' : "";
+                }
+
+                this.streamElement.textContent = content;
+                this.streamElement.scrollTop = this.streamElement.scrollHeight;
+            }
+
+            updateFilter() {
+                const pattern = this.filterInput.value.trim();
+                this.filterInput.classList.remove('regex-error');
+
+                if (!pattern) {
+                    this.regexFilter = null;
+                    this.render();
+                    return;
+                }
 
-        function updateFilter() {
-            const pattern = filterInput.value.trim();
-            filterInput.classList.remove('regex-error');
-            if (pattern) {
                 try {
-                    regexFilter = new RegExp(pattern);
+                    this.regexFilter = new RegExp(pattern);
                 } catch (e) {
                     console.error("Invalid regex pattern:", e);
-                    regexFilter = null;
-                    filterInput.classList.add('regex-error');
-                    return
+                    this.regexFilter = null;
+                    this.filterInput.classList.add('regex-error');
+                    return;
                 }
-            } else {
-                regexFilter = null;
-            }
 
-            render();
+                this.render();
+            }
         }
 
-        filterInput.addEventListener('input', updateFilter);
-        document.getElementById('clear-button').addEventListener('click', () => {
-            filterInput.value = "";
-            regexFilter = null;
-            render();
+        // Initialize both log streams
+        document.addEventListener('DOMContentLoaded', () => {
+            new LogStream(
+                document.getElementById('proxy-log-stream'),
+                document.getElementById('proxy-filter-input'),
+                document.getElementById('proxy-clear-button'),
+                "/logs/streamSSE/proxy"
+            );
+
+            new LogStream(
+                document.getElementById('upstream-log-stream'),
+                document.getElementById('upstream-filter-input'),
+                document.getElementById('upstream-clear-button'),
+                "/logs/streamSSE/upstream"
+            );
+
+            // Initialize clickable headers
+            document.querySelectorAll('h2').forEach(header => {
+                header.addEventListener('click', () => {
+                    const column = header.closest('.log-column');
+                    column.classList.toggle('minimized');
+                });
+            });
         });
-        setupEventSource();
-        updateFilter();
     </script>
 </body>
 </html>

proxy/logMonitor.go

@@ -2,11 +2,21 @@ package proxy
 
 import (
 	"container/ring"
+	"fmt"
 	"io"
 	"os"
 	"sync"
 )
 
+type LogLevel int
+
+const (
+	LevelDebug LogLevel = iota
+	LevelInfo
+	LevelWarn
+	LevelError
+)
+
 type LogMonitor struct {
 	clients  map[chan []byte]bool
 	mu       sync.RWMutex
@@ -15,6 +25,10 @@ type LogMonitor struct {
 
 	// typically this can be os.Stdout
 	stdout io.Writer
+
+	// logging levels
+	level  LogLevel
+	prefix string
 }
 
 func NewLogMonitor() *LogMonitor {
@@ -26,6 +40,8 @@ func NewLogMonitorWriter(stdout io.Writer) *LogMonitor {
 		clients: make(map[chan []byte]bool),
 		buffer:  ring.New(10 * 1024), // keep 10KB of buffered logs
 		stdout:  stdout,
+		level:   LevelInfo,
+		prefix:  "",
 	}
 }
 
@@ -94,3 +110,77 @@ func (w *LogMonitor) broadcast(msg []byte) {
 		}
 	}
 }
+
+func (w *LogMonitor) SetPrefix(prefix string) {
+	w.mu.Lock()
+	defer w.mu.Unlock()
+	w.prefix = prefix
+}
+
+func (w *LogMonitor) SetLogLevel(level LogLevel) {
+	w.mu.Lock()
+	defer w.mu.Unlock()
+	w.level = level
+}
+
+func (w *LogMonitor) formatMessage(level string, msg string) []byte {
+	prefix := ""
+	if w.prefix != "" {
+		prefix = fmt.Sprintf("[%s] ", w.prefix)
+	}
+	return []byte(fmt.Sprintf("%s[%s] %s\n", prefix, level, msg))
+}
+
+func (w *LogMonitor) log(level LogLevel, msg string) {
+	if level < w.level {
+		return
+	}
+	w.Write(w.formatMessage(level.String(), msg))
+}
+
+func (w *LogMonitor) Debug(msg string) {
+	w.log(LevelDebug, msg)
+}
+
+func (w *LogMonitor) Info(msg string) {
+	w.log(LevelInfo, msg)
+}
+
+func (w *LogMonitor) Warn(msg string) {
+	w.log(LevelWarn, msg)
+}
+
+func (w *LogMonitor) Error(msg string) {
+	w.log(LevelError, msg)
+}
+
+func (w *LogMonitor) Debugf(format string, args ...interface{}) {
+	w.log(LevelDebug, fmt.Sprintf(format, args...))
+}
+
+func (w *LogMonitor) Infof(format string, args ...interface{}) {
+	w.log(LevelInfo, fmt.Sprintf(format, args...))
+}
+
+func (w *LogMonitor) Warnf(format string, args ...interface{}) {
+	w.log(LevelWarn, fmt.Sprintf(format, args...))
+}
+
+func (w *LogMonitor) Errorf(format string, args ...interface{}) {
+	w.log(LevelError, fmt.Sprintf(format, args...))
+}
+
+func (l LogLevel) String() string {
+	switch l {
+	case LevelDebug:
+		return "DEBUG"
+	case LevelInfo:
+		return "INFO"
+	case LevelWarn:
+		return "WARN"
+	case LevelError:
+		return "ERROR"
+	default:
+		return "UNKNOWN"
+	}
+}

proxy/process.go

@@ -30,10 +30,15 @@ const (
 )
 
 type Process struct {
-	ID         string
-	config     ModelConfig
-	cmd        *exec.Cmd
-	logMonitor *LogMonitor
+	ID     string
+	config ModelConfig
+	cmd    *exec.Cmd
+
+	// for p.cmd.Wait() select { ... }
+	cmdWaitChan chan error
+
+	processLogger *LogMonitor
+	proxyLogger   *LogMonitor
 
 	healthCheckTimeout      int
 	healthCheckLoopInterval time.Duration
@@ -53,13 +58,15 @@ type Process struct {
 	shutdownCancel context.CancelFunc
 }
 
-func NewProcess(ID string, healthCheckTimeout int, config ModelConfig, logMonitor *LogMonitor) *Process {
+func NewProcess(ID string, healthCheckTimeout int, config ModelConfig, processLogger *LogMonitor, proxyLogger *LogMonitor) *Process {
 	ctx, cancel := context.WithCancel(context.Background())
 	return &Process{
 		ID:                      ID,
 		config:                  config,
 		cmd:                     nil,
-		logMonitor:              logMonitor,
+		cmdWaitChan:             make(chan error, 1),
+		processLogger:           processLogger,
+		proxyLogger:             proxyLogger,
 		healthCheckTimeout:      healthCheckTimeout,
 		healthCheckLoopInterval: 5 * time.Second, /* default, can not be set by user - used for testing */
 		state:                   StateStopped,
@@ -68,6 +75,11 @@ func NewProcess(ID string, healthCheckTimeout int, config ModelConfig, logMonito
 	}
 }
 
+// LogMonitor returns the log monitor associated with the process.
+func (p *Process) LogMonitor() *LogMonitor {
+	return p.processLogger
+}
+
 // custom error types for swapping state
 var (
 	ErrExpectedStateMismatch  = errors.New("expected state mismatch")
@@ -81,14 +93,17 @@ func (p *Process) swapState(expectedState, newState ProcessState) (ProcessState,
 	defer p.stateMutex.Unlock()
 
 	if p.state != expectedState {
+		p.proxyLogger.Warnf("<%s> swapState() Unexpected current state %s, expected %s", p.ID, p.state, expectedState)
 		return p.state, ErrExpectedStateMismatch
 	}
 
 	if !isValidTransition(p.state, newState) {
+		p.proxyLogger.Warnf("<%s> swapState() Invalid state transition from %s to %s", p.ID, p.state, newState)
 		return p.state, ErrInvalidStateTransition
 	}
 
 	p.state = newState
+	p.proxyLogger.Debugf("<%s> swapState() State transitioned from %s to %s", p.ID, expectedState, newState)
 	return p.state, nil
 }
 
@@ -152,15 +167,15 @@ func (p *Process) start() error {
 	defer p.waitStarting.Done()
 
 	p.cmd = exec.Command(args[0], args[1:]...)
-	p.cmd.Stdout = p.logMonitor
-	p.cmd.Stderr = p.logMonitor
+	p.cmd.Stdout = p.processLogger
+	p.cmd.Stderr = p.processLogger
 	p.cmd.Env = p.config.Env
 
 	err = p.cmd.Start()
 
 	// Set process state to failed
 	if err != nil {
-		if curState, swapErr := p.swapState(StateStarting, StateFailed); err != nil {
+		if curState, swapErr := p.swapState(StateStarting, StateFailed); swapErr != nil {
 			return fmt.Errorf(
 				"failed to start command and state swap failed. command error: %v, current state: %v, state swap error: %v",
 				err, curState, swapErr,
@@ -169,6 +184,13 @@ func (p *Process) start() error {
 		return fmt.Errorf("start() failed: %v", err)
 	}
 
+	// Capture the exit error for later signaling
+	go func() {
+		exitErr := p.cmd.Wait()
+		p.proxyLogger.Debugf("<%s> cmd.Wait() returned error: %v", p.ID, exitErr)
+		p.cmdWaitChan <- exitErr
+	}()
+
 	// One of three things can happen at this stage:
 	// 1. The command exits unexpectedly
 	// 2. The health check fails
@@ -212,17 +234,34 @@ func (p *Process) start() error {
 				}
 			case <-p.shutdownCtx.Done():
 				return errors.New("health check interrupted due to shutdown")
+			case exitErr := <-p.cmdWaitChan:
+				if exitErr != nil {
+					p.proxyLogger.Warnf("<%s> upstream command exited prematurely with error: %v", p.ID, exitErr)
+					if curState, err := p.swapState(StateStarting, StateFailed); err != nil {
+						return fmt.Errorf("upstream command exited unexpectedly: %s AND state swap failed: %v, current state: %v", exitErr.Error(), err, curState)
+					} else {
+						return fmt.Errorf("upstream command exited unexpectedly: %s", exitErr.Error())
+					}
+				} else {
+					p.proxyLogger.Warnf("<%s> upstream command exited prematurely but successfully", p.ID)
+					if curState, err := p.swapState(StateStarting, StateFailed); err != nil {
+						return fmt.Errorf("upstream command exited prematurely but successfully AND state swap failed: %v, current state: %v", err, curState)
+					} else {
+						return fmt.Errorf("upstream command exited prematurely but successfully")
+					}
+				}
 			default:
 				if err := p.checkHealthEndpoint(healthURL); err == nil {
+					p.proxyLogger.Infof("<%s> Health check passed on %s", p.ID, healthURL)
 					cancelHealthCheck()
 					break loop
 				} else {
 					if strings.Contains(err.Error(), "connection refused") {
 						endTime, _ := checkDeadline.Deadline()
 						ttl := time.Until(endTime)
-						fmt.Fprintf(p.logMonitor, "!!! Connection refused on %s, ttl %.0fs\n", healthURL, ttl.Seconds())
+						p.proxyLogger.Infof("<%s> Connection refused on %s, giving up in %.0fs", p.ID, healthURL, ttl.Seconds())
 					} else {
-						fmt.Fprintf(p.logMonitor, "!!! Health check error: %v\n", err)
+						p.proxyLogger.Infof("<%s> Health check error on %s, %v", p.ID, healthURL, err)
 					}
 				}
 			}
@@ -246,7 +285,7 @@ func (p *Process) start() error {
 				p.inFlightRequests.Wait()
 
 				if time.Since(p.lastRequestHandled) > maxDuration {
-					fmt.Fprintf(p.logMonitor, "!!! Unloading model %s, TTL of %ds reached.\n", p.ID, p.config.UnloadAfter)
+					p.proxyLogger.Infof("<%s> Unloading model, TTL of %ds reached", p.ID, p.config.UnloadAfter)
 					p.Stop()
 					return
 				}
@@ -262,12 +301,17 @@ func (p *Process) start() error {
 }
 
 func (p *Process) Stop() {
+	if !isValidTransition(p.CurrentState(), StateStopping) {
+		return
+	}
+
 	// wait for any inflight requests before proceeding
 	p.inFlightRequests.Wait()
+	p.proxyLogger.Debugf("<%s> Stopping process", p.ID)
 
 	// calling Stop() when state is invalid is a no-op
 	if curState, err := p.swapState(StateReady, StateStopping); err != nil {
-		fmt.Fprintf(p.logMonitor, "!!! Info - Stop() Ready -> StateStopping err: %v, current state: %v\n", err, curState)
+		p.proxyLogger.Infof("<%s> Stop() Ready -> StateStopping err: %v, current state: %v", p.ID, err, curState)
 		return
 	}
 
@@ -275,7 +319,7 @@ func (p *Process) Stop() {
 	p.stopCommand(5 * time.Second)
 
 	if curState, err := p.swapState(StateStopping, StateStopped); err != nil {
-		fmt.Fprintf(p.logMonitor, "!!! Info - Stop() StateStopping -> StateStopped err: %v, current state: %v\n", err, curState)
+		p.proxyLogger.Infof("<%s> Stop() StateStopping -> StateStopped err: %v, current state: %v", p.ID, err, curState)
 	}
 }
 
@@ -291,47 +335,51 @@ func (p *Process) Shutdown() {
 // stopCommand will send a SIGTERM to the process and wait for it to exit.
 // If it does not exit within 5 seconds, it will send a SIGKILL.
 func (p *Process) stopCommand(sigtermTTL time.Duration) {
+	stopStartTime := time.Now()
+	defer func() {
+		p.proxyLogger.Debugf("<%s> stopCommand took %v", p.ID, time.Since(stopStartTime))
+	}()
+
 	sigtermTimeout, cancelTimeout := context.WithTimeout(context.Background(), sigtermTTL)
 	defer cancelTimeout()
 
-	sigtermNormal := make(chan error, 1)
-	go func() {
-		sigtermNormal <- p.cmd.Wait()
-	}()
-
 	if p.cmd == nil || p.cmd.Process == nil {
-		fmt.Fprintf(p.logMonitor, "!!! process [%s] cmd or cmd.Process is nil", p.ID)
+		p.proxyLogger.Warnf("<%s> cmd or cmd.Process is nil", p.ID)
 		return
 	}
 
-	p.cmd.Process.Signal(syscall.SIGTERM)
+	if err := p.terminateProcess(); err != nil {
+		p.proxyLogger.Infof("<%s> Failed to gracefully terminate process: %v", p.ID, err)
+	}
 
 	select {
 	case <-sigtermTimeout.Done():
-		fmt.Fprintf(p.logMonitor, "!!! process [%s] timed out waiting to stop, sending KILL signal\n", p.ID)
+		p.proxyLogger.Infof("<%s> Process timed out waiting to stop, sending KILL signal", p.ID)
 		p.cmd.Process.Kill()
-	case err := <-sigtermNormal:
+	case err := <-p.cmdWaitChan:
+		// Note: in start(), p.cmdWaitChan also has a select { ... }. That should be OK
+		// because if we make it here then the cmd has been successfully running and made it
+		// through the health check. There is a possibility that ithe cmd crashed after the health check
+		// succeeded but that's not a case llama-swap is handling for now.
 		if err != nil {
 			if errno, ok := err.(syscall.Errno); ok {
-				fmt.Fprintf(p.logMonitor, "!!! process [%s] errno >> %v\n", p.ID, errno)
+				p.proxyLogger.Errorf("<%s> errno >> %v", p.ID, errno)
 			} else if exitError, ok := err.(*exec.ExitError); ok {
 				if strings.Contains(exitError.String(), "signal: terminated") {
-					fmt.Fprintf(p.logMonitor, "!!! process [%s] stopped OK\n", p.ID)
+					p.proxyLogger.Infof("<%s> Process stopped OK", p.ID)
 				} else if strings.Contains(exitError.String(), "signal: interrupt") {
-					fmt.Fprintf(p.logMonitor, "!!! process [%s] interrupted OK\n", p.ID)
+					p.proxyLogger.Infof("<%s> Process interrupted OK", p.ID)
 				} else {
-					fmt.Fprintf(p.logMonitor, "!!! process [%s] ExitError >> %v, exit code: %d\n", p.ID, exitError, exitError.ExitCode())
+					p.proxyLogger.Warnf("<%s> ExitError >> %v, exit code: %d", p.ID, exitError, exitError.ExitCode())
 				}
-
 			} else {
-				fmt.Fprintf(p.logMonitor, "!!! process [%s] exited >> %v\n", p.ID, err)
+				p.proxyLogger.Errorf("<%s> Process exited >> %v", p.ID, err)
 			}
 		}
 	}
 }
 
 func (p *Process) checkHealthEndpoint(healthURL string) error {
-
 	client := &http.Client{
 		Timeout: 500 * time.Millisecond,
 	}
@@ -356,6 +404,8 @@ func (p *Process) checkHealthEndpoint(healthURL string) error {
 }
 
 func (p *Process) ProxyRequest(w http.ResponseWriter, r *http.Request) {
+	requestBeginTime := time.Now()
+	var startDuration time.Duration
 
 	// prevent new requests from being made while stopping or irrecoverable
 	currentState := p.CurrentState()
@@ -372,11 +422,13 @@ func (p *Process) ProxyRequest(w http.ResponseWriter, r *http.Request) {
 
 	// start the process on demand
 	if p.CurrentState() != StateReady {
+		beginStartTime := time.Now()
 		if err := p.start(); err != nil {
 			errstr := fmt.Sprintf("unable to start process: %s", err)
 			http.Error(w, errstr, http.StatusBadGateway)
 			return
 		}
+		startDuration = time.Since(beginStartTime)
 	}
 
 	proxyTo := p.config.Proxy
@@ -420,4 +472,8 @@ func (p *Process) ProxyRequest(w http.ResponseWriter, r *http.Request) {
 			return
 		}
 	}
+
+	totalTime := time.Since(requestBeginTime)
+	p.proxyLogger.Debugf("<%s> request %s - start: %v, total: %v",
+		p.ID, r.RequestURI, startDuration, totalTime)
 }

proxy/process_stop.go

@@ -0,0 +1,9 @@
+//go:build !windows
+
+package proxy
+
+import "syscall"
+
+func (p *Process) terminateProcess() error {
+	return p.cmd.Process.Signal(syscall.SIGTERM)
+}

proxy/process_stop_windows.go

@@ -0,0 +1,14 @@
+//go:build windows
+
+package proxy
+
+import (
+	"fmt"
+	"os/exec"
+)
+
+func (p *Process) terminateProcess() error {
+	pid := fmt.Sprintf("%d", p.cmd.Process.Pid)
+	cmd := exec.Command("taskkill", "/f", "/t", "/pid", pid)
+	return cmd.Run()
+}

proxy/process_test.go

@@ -2,7 +2,6 @@ package proxy
 
 import (
 	"fmt"
-	"io"
 	"net/http"
 	"net/http/httptest"
 	"os"
@@ -13,13 +12,26 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
+var (
+	debugLogger = NewLogMonitorWriter(os.Stdout)
+)
+
+func init() {
+	// flip to help with debugging tests
+	if false {
+		debugLogger.SetLogLevel(LevelDebug)
+	} else {
+		debugLogger.SetLogLevel(LevelError)
+	}
+}
+
 func TestProcess_AutomaticallyStartsUpstream(t *testing.T) {
-	logMonitor := NewLogMonitorWriter(io.Discard)
+
 	expectedMessage := "testing91931"
 	config := getTestSimpleResponderConfig(expectedMessage)
 
 	// Create a process
-	process := NewProcess("test-process", 5, config, logMonitor)
+	process := NewProcess("test-process", 5, config, debugLogger, debugLogger)
 	defer process.Stop()
 
 	req := httptest.NewRequest("GET", "/test", nil)
@@ -52,11 +64,10 @@ func TestProcess_AutomaticallyStartsUpstream(t *testing.T) {
 // are all handled successfully, even though they all may ask for the process to .start()
 func TestProcess_WaitOnMultipleStarts(t *testing.T) {
 
-	logMonitor := NewLogMonitorWriter(io.Discard)
 	expectedMessage := "testing91931"
 	config := getTestSimpleResponderConfig(expectedMessage)
 
-	process := NewProcess("test-process", 5, config, logMonitor)
+	process := NewProcess("test-process", 5, config, debugLogger, debugLogger)
 	defer process.Stop()
 
 	var wg sync.WaitGroup
@@ -84,7 +95,7 @@ func TestProcess_BrokenModelConfig(t *testing.T) {
 		CheckEndpoint: "/health",
 	}
 
-	process := NewProcess("broken", 1, config, NewLogMonitor())
+	process := NewProcess("broken", 1, config, debugLogger, debugLogger)
 
 	req := httptest.NewRequest("GET", "/", nil)
 	w := httptest.NewRecorder()
@@ -109,7 +120,7 @@ func TestProcess_UnloadAfterTTL(t *testing.T) {
 	config.UnloadAfter = 3 // seconds
 	assert.Equal(t, 3, config.UnloadAfter)
 
-	process := NewProcess("ttl_test", 2, config, NewLogMonitorWriter(io.Discard))
+	process := NewProcess("ttl_test", 2, config, debugLogger, debugLogger)
 	defer process.Stop()
 
 	// this should take 4 seconds
@@ -151,7 +162,7 @@ func TestProcess_LowTTLValue(t *testing.T) {
 	config.UnloadAfter = 1 // second
 	assert.Equal(t, 1, config.UnloadAfter)
 
-	process := NewProcess("ttl", 2, config, NewLogMonitorWriter(os.Stdout))
+	process := NewProcess("ttl", 2, config, debugLogger, debugLogger)
 	defer process.Stop()
 
 	for i := 0; i < 100; i++ {
@@ -178,7 +189,7 @@ func TestProcess_HTTPRequestsHaveTimeToFinish(t *testing.T) {
 
 	expectedMessage := "12345"
 	config := getTestSimpleResponderConfig(expectedMessage)
-	process := NewProcess("t", 10, config, NewLogMonitorWriter(os.Stdout))
+	process := NewProcess("t", 10, config, debugLogger, debugLogger)
 	defer process.Stop()
 
 	results := map[string]string{
@@ -255,9 +266,8 @@ func TestProcess_SwapState(t *testing.T) {
 
 	for _, test := range tests {
 		t.Run(test.name, func(t *testing.T) {
-			p := &Process{
-				state: test.currentState,
-			}
+			p := NewProcess("test", 10, getTestSimpleResponderConfig("test"), debugLogger, debugLogger)
+			p.state = test.currentState
 
 			resultState, err := p.swapState(test.expectedState, test.newState)
 			if err != nil && test.expectedError == nil {
@@ -282,7 +292,6 @@ func TestProcess_ShutdownInterruptsHealthCheck(t *testing.T) {
 		t.Skip("skipping long shutdown test")
 	}
 
-	logMonitor := NewLogMonitorWriter(io.Discard)
 	expectedMessage := "testing91931"
 
 	// make a config where the healthcheck will always fail because port is wrong
@@ -290,7 +299,7 @@ func TestProcess_ShutdownInterruptsHealthCheck(t *testing.T) {
 	config.Proxy = "http://localhost:9998/test"
 
 	healthCheckTTLSeconds := 30
-	process := NewProcess("test-process", healthCheckTTLSeconds, config, logMonitor)
+	process := NewProcess("test-process", healthCheckTTLSeconds, config, debugLogger, debugLogger)
 
 	// make it a lot faster
 	process.healthCheckLoopInterval = time.Second
@@ -311,3 +320,23 @@ func TestProcess_ShutdownInterruptsHealthCheck(t *testing.T) {
 	assert.ErrorContains(t, err, "health check interrupted due to shutdown")
 	assert.Equal(t, StateShutdown, process.CurrentState())
 }
+
+func TestProcess_ExitInterruptsHealthCheck(t *testing.T) {
+	if testing.Short() {
+		t.Skip("skipping Exit Interrupts Health Check test")
+	}
+
+	// should run and exit but interrupt the long checkHealthTimeout
+	checkHealthTimeout := 5
+	config := ModelConfig{
+		Cmd:           "sleep 1",
+		Proxy:         "http://127.0.0.1:9913",
+		CheckEndpoint: "/health",
+	}
+
+	process := NewProcess("sleepy", checkHealthTimeout, config, debugLogger, debugLogger)
+	process.healthCheckLoopInterval = time.Second // make it faster
+	err := process.start()
+	assert.Equal(t, "upstream command exited prematurely but successfully", err.Error())
+	assert.Equal(t, process.CurrentState(), StateFailed)
+}

proxy/processgroup.go

@@ -0,0 +1,113 @@
+package proxy
+
+import (
+	"fmt"
+	"net/http"
+	"slices"
+	"sync"
+)
+
+type ProcessGroup struct {
+	sync.Mutex
+
+	config     Config
+	id         string
+	swap       bool
+	exclusive  bool
+	persistent bool
+
+	proxyLogger    *LogMonitor
+	upstreamLogger *LogMonitor
+
+	// map of current processes
+	processes       map[string]*Process
+	lastUsedProcess string
+}
+
+func NewProcessGroup(id string, config Config, proxyLogger *LogMonitor, upstreamLogger *LogMonitor) *ProcessGroup {
+	groupConfig, ok := config.Groups[id]
+	if !ok {
+		panic("Unable to find configuration for group id: " + id)
+	}
+
+	pg := &ProcessGroup{
+		id:             id,
+		config:         config,
+		swap:           groupConfig.Swap,
+		exclusive:      groupConfig.Exclusive,
+		persistent:     groupConfig.Persistent,
+		proxyLogger:    proxyLogger,
+		upstreamLogger: upstreamLogger,
+		processes:      make(map[string]*Process),
+	}
+
+	// Create a Process for each member in the group
+	for _, modelID := range groupConfig.Members {
+		modelConfig, modelID, _ := pg.config.FindConfig(modelID)
+		process := NewProcess(modelID, pg.config.HealthCheckTimeout, modelConfig, pg.upstreamLogger, pg.proxyLogger)
+		pg.processes[modelID] = process
+	}
+
+	return pg
+}
+
+// ProxyRequest proxies a request to the specified model
+func (pg *ProcessGroup) ProxyRequest(modelID string, writer http.ResponseWriter, request *http.Request) error {
+	if !pg.HasMember(modelID) {
+		return fmt.Errorf("model %s not part of group %s", modelID, pg.id)
+	}
+
+	if pg.swap {
+		pg.Lock()
+		if pg.lastUsedProcess != modelID {
+			if pg.lastUsedProcess != "" {
+				pg.processes[pg.lastUsedProcess].Stop()
+			}
+			pg.lastUsedProcess = modelID
+		}
+		pg.Unlock()
+	}
+
+	pg.processes[modelID].ProxyRequest(writer, request)
+	return nil
+}
+
+func (pg *ProcessGroup) HasMember(modelName string) bool {
+	return slices.Contains(pg.config.Groups[pg.id].Members, modelName)
+}
+
+func (pg *ProcessGroup) StopProcesses() {
+	pg.Lock()
+	defer pg.Unlock()
+	pg.stopProcesses()
+}
+
+// stopProcesses stops all processes in the group
+func (pg *ProcessGroup) stopProcesses() {
+	if len(pg.processes) == 0 {
+		return
+	}
+
+	// stop Processes in parallel
+	var wg sync.WaitGroup
+	for _, process := range pg.processes {
+		wg.Add(1)
+		go func(process *Process) {
+			defer wg.Done()
+			process.Stop()
+		}(process)
+	}
+	wg.Wait()
+}
+
+func (pg *ProcessGroup) Shutdown() {
+	var wg sync.WaitGroup
+	for _, process := range pg.processes {
+		wg.Add(1)
+		go func(process *Process) {
+			defer wg.Done()
+			process.Shutdown()
+		}(process)
+	}
+	wg.Wait()
+}

proxy/processgroup_test.go

@@ -0,0 +1,96 @@
+package proxy
+
+import (
+	"bytes"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+var processGroupTestConfig = AddDefaultGroupToConfig(Config{
+	HealthCheckTimeout: 15,
+	Models: map[string]ModelConfig{
+		"model1": getTestSimpleResponderConfig("model1"),
+		"model2": getTestSimpleResponderConfig("model2"),
+		"model3": getTestSimpleResponderConfig("model3"),
+		"model4": getTestSimpleResponderConfig("model4"),
+		"model5": getTestSimpleResponderConfig("model5"),
+	},
+	Groups: map[string]GroupConfig{
+		"G1": {
+			Swap:      true,
+			Exclusive: true,
+			Members:   []string{"model1", "model2"},
+		},
+		"G2": {
+			Swap:      false,
+			Exclusive: true,
+			Members:   []string{"model3", "model4"},
+		},
+	},
+})
+
+func TestProcessGroup_DefaultHasCorrectModel(t *testing.T) {
+	pg := NewProcessGroup(DEFAULT_GROUP_ID, processGroupTestConfig, testLogger, testLogger)
+	assert.True(t, pg.HasMember("model5"))
+}
+
+func TestProcessGroup_HasMember(t *testing.T) {
+	pg := NewProcessGroup("G1", processGroupTestConfig, testLogger, testLogger)
+	assert.True(t, pg.HasMember("model1"))
+	assert.True(t, pg.HasMember("model2"))
+	assert.False(t, pg.HasMember("model3"))
+}
+
+func TestProcessGroup_ProxyRequestSwapIsTrue(t *testing.T) {
+	pg := NewProcessGroup("G1", processGroupTestConfig, testLogger, testLogger)
+	defer pg.StopProcesses()
+
+	tests := []string{"model1", "model2"}
+
+	for _, modelName := range tests {
+		t.Run(modelName, func(t *testing.T) {
+			reqBody := `{"x", "y"}`
+			req := httptest.NewRequest("POST", "/v1/chat/completions", bytes.NewBufferString(reqBody))
+			w := httptest.NewRecorder()
+
+			assert.NoError(t, pg.ProxyRequest(modelName, w, req))
+			assert.Equal(t, http.StatusOK, w.Code)
+			assert.Contains(t, w.Body.String(), modelName)
+
+			// make sure only one process is in the running state
+			count := 0
+			for _, process := range pg.processes {
+				if process.CurrentState() == StateReady {
+					count++
+				}
+			}
+			assert.Equal(t, 1, count)
+		})
+	}
+}
+
+func TestProcessGroup_ProxyRequestSwapIsFalse(t *testing.T) {
+	pg := NewProcessGroup("G2", processGroupTestConfig, testLogger, testLogger)
+	defer pg.StopProcesses()
+
+	tests := []string{"model3", "model4"}
+
+	for _, modelName := range tests {
+		t.Run(modelName, func(t *testing.T) {
+			reqBody := `{"x", "y"}`
+			req := httptest.NewRequest("POST", "/v1/chat/completions", bytes.NewBufferString(reqBody))
+			w := httptest.NewRecorder()
+			assert.NoError(t, pg.ProxyRequest(modelName, w, req))
+			assert.Equal(t, http.StatusOK, w.Code)
+			assert.Contains(t, w.Body.String(), modelName)
+		})
+	}
+
+	// make sure all the processes are running
+	for _, process := range pg.processes {
+		assert.Equal(t, StateReady, process.CurrentState())
+	}
+}

proxy/proxymanager.go

@@ -7,6 +7,7 @@ import (
 	"io"
 	"mime/multipart"
 	"net/http"
+	"os"
 	"sort"
 	"strconv"
 	"strings"
@@ -25,61 +26,111 @@ const (
 type ProxyManager struct {
 	sync.Mutex
 
-	config           *Config
-	currentProcesses map[string]*Process
-	logMonitor       *LogMonitor
-	ginEngine        *gin.Engine
+	config    Config
+	ginEngine *gin.Engine
+
+	// logging
+	proxyLogger    *LogMonitor
+	upstreamLogger *LogMonitor
+	muxLogger      *LogMonitor
+
+	processGroups map[string]*ProcessGroup
 }
 
-func New(config *Config) *ProxyManager {
-	pm := &ProxyManager{
-		config:           config,
-		currentProcesses: make(map[string]*Process),
-		logMonitor:       NewLogMonitor(),
-		ginEngine:        gin.New(),
-	}
+func New(config Config) *ProxyManager {
+	// set up loggers
+	stdoutLogger := NewLogMonitorWriter(os.Stdout)
+	upstreamLogger := NewLogMonitorWriter(stdoutLogger)
+	proxyLogger := NewLogMonitorWriter(stdoutLogger)
 
 	if config.LogRequests {
-		pm.ginEngine.Use(func(c *gin.Context) {
-			// Start timer
-			start := time.Now()
-
-			// capture these because /upstream/:model rewrites them in c.Next()
-			clientIP := c.ClientIP()
-			method := c.Request.Method
-			path := c.Request.URL.Path
-
-			// Process request
-			c.Next()
-
-			// Stop timer
-			duration := time.Since(start)
-
-			statusCode := c.Writer.Status()
-			bodySize := c.Writer.Size()
-
-			fmt.Fprintf(pm.logMonitor, "[llama-swap] %s [%s] \"%s %s %s\" %d %d \"%s\" %v\n",
-				clientIP,
-				time.Now().Format("2006-01-02 15:04:05"),
-				method,
-				path,
-				c.Request.Proto,
-				statusCode,
-				bodySize,
-				c.Request.UserAgent(),
-				duration,
-			)
-		})
+		proxyLogger.Warn("LogRequests configuration is deprecated. Use logLevel instead.")
 	}
 
-	// see: https://github.com/mostlygeek/llama-swap/issues/42
+	switch strings.ToLower(strings.TrimSpace(config.LogLevel)) {
+	case "debug":
+		proxyLogger.SetLogLevel(LevelDebug)
+		upstreamLogger.SetLogLevel(LevelDebug)
+	case "info":
+		proxyLogger.SetLogLevel(LevelInfo)
+		upstreamLogger.SetLogLevel(LevelInfo)
+	case "warn":
+		proxyLogger.SetLogLevel(LevelWarn)
+		upstreamLogger.SetLogLevel(LevelWarn)
+	case "error":
+		proxyLogger.SetLogLevel(LevelError)
+		upstreamLogger.SetLogLevel(LevelError)
+	default:
+		proxyLogger.SetLogLevel(LevelInfo)
+		upstreamLogger.SetLogLevel(LevelInfo)
+	}
+
+	pm := &ProxyManager{
+		config:    config,
+		ginEngine: gin.New(),
+
+		proxyLogger:    proxyLogger,
+		muxLogger:      stdoutLogger,
+		upstreamLogger: upstreamLogger,
+
+		processGroups: make(map[string]*ProcessGroup),
+	}
+
+	// create the process groups
+	for groupID := range config.Groups {
+		processGroup := NewProcessGroup(groupID, config, proxyLogger, upstreamLogger)
+		pm.processGroups[groupID] = processGroup
+	}
+
+	pm.ginEngine.Use(func(c *gin.Context) {
+		// Start timer
+		start := time.Now()
+
+		// capture these because /upstream/:model rewrites them in c.Next()
+		clientIP := c.ClientIP()
+		method := c.Request.Method
+		path := c.Request.URL.Path
+
+		// Process request
+		c.Next()
+
+		// Stop timer
+		duration := time.Since(start)
+
+		statusCode := c.Writer.Status()
+		bodySize := c.Writer.Size()
+
+		pm.proxyLogger.Infof("Request %s \"%s %s %s\" %d %d \"%s\" %v",
+			clientIP,
+			method,
+			path,
+			c.Request.Proto,
+			statusCode,
+			bodySize,
+			c.Request.UserAgent(),
+			duration,
+		)
+	})
+
+	// see: issue: #81, #77 and #42 for CORS issues
 	// respond with permissive OPTIONS for any endpoint
 	pm.ginEngine.Use(func(c *gin.Context) {
 		if c.Request.Method == "OPTIONS" {
 			c.Header("Access-Control-Allow-Origin", "*")
-			c.Header("Access-Control-Allow-Methods", "GET, POST, OPTIONS")
-			c.Header("Access-Control-Allow-Headers", "Content-Type, Authorization")
-			c.AbortWithStatus(204)
+			c.Header("Access-Control-Allow-Methods", "GET, POST, PUT, PATCH, DELETE, OPTIONS")
+
+			// allow whatever the client requested by default
+			if headers := c.Request.Header.Get("Access-Control-Request-Headers"); headers != "" {
+				sanitized := SanitizeAccessControlRequestHeaderValues(headers)
+				c.Header("Access-Control-Allow-Headers", sanitized)
+			} else {
+				c.Header(
+					"Access-Control-Allow-Headers",
+					"Content-Type, Authorization, Accept, X-Requested-With",
+				)
+			}
+			c.Header("Access-Control-Max-Age", "86400")
+			c.AbortWithStatus(http.StatusNoContent)
 			return
 		}
 		c.Next()
@@ -104,6 +155,8 @@ func New(config *Config) *ProxyManager {
 	pm.ginEngine.GET("/logs", pm.sendLogsHandlers)
 	pm.ginEngine.GET("/logs/stream", pm.streamLogsHandler)
 	pm.ginEngine.GET("/logs/streamSSE", pm.streamLogsHandlerSSE)
+	pm.ginEngine.GET("/logs/stream/:logMonitorID", pm.streamLogsHandler)
+	pm.ginEngine.GET("/logs/streamSSE/:logMonitorID", pm.streamLogsHandlerSSE)
 
 	pm.ginEngine.GET("/upstream", pm.upstreamIndex)
 	pm.ginEngine.Any("/upstream/:model_id/*upstreamPath", pm.proxyToUpstream)
@@ -155,27 +208,17 @@ func (pm *ProxyManager) StopProcesses() {
 	pm.Lock()
 	defer pm.Unlock()
 
-	pm.stopProcesses()
-}
-
-// for internal usage
-func (pm *ProxyManager) stopProcesses() {
-	if len(pm.currentProcesses) == 0 {
-		return
-	}
-
 	// stop Processes in parallel
 	var wg sync.WaitGroup
-	for _, process := range pm.currentProcesses {
+	for _, processGroup := range pm.processGroups {
 		wg.Add(1)
-		go func(process *Process) {
+		go func(processGroup *ProcessGroup) {
 			defer wg.Done()
-			process.Stop()
-		}(process)
+			processGroup.stopProcesses()
+		}(processGroup)
 	}
-	wg.Wait()
 
-	pm.currentProcesses = make(map[string]*Process)
+	wg.Wait()
 }
 
 // Shutdown is called to shutdown all upstream processes
@@ -184,18 +227,44 @@ func (pm *ProxyManager) Shutdown() {
 	pm.Lock()
 	defer pm.Unlock()
 
-	// shutdown process in parallel
+	pm.proxyLogger.Debug("Shutdown() called in proxy manager")
+
 	var wg sync.WaitGroup
-	for _, process := range pm.currentProcesses {
+	// Send shutdown signal to all process in groups
+	for _, processGroup := range pm.processGroups {
 		wg.Add(1)
-		go func(process *Process) {
+		go func(processGroup *ProcessGroup) {
 			defer wg.Done()
-			process.Shutdown()
-		}(process)
+			processGroup.Shutdown()
+		}(processGroup)
 	}
 	wg.Wait()
 }
 
+func (pm *ProxyManager) swapProcessGroup(requestedModel string) (*ProcessGroup, string, error) {
+	// de-alias the real model name and get a real one
+	realModelName, found := pm.config.RealModelName(requestedModel)
+	if !found {
+		return nil, realModelName, fmt.Errorf("could not find real modelID for %s", requestedModel)
+	}
+
+	processGroup := pm.findGroupByModelName(realModelName)
+	if processGroup == nil {
+		return nil, realModelName, fmt.Errorf("could not find process group for model %s", requestedModel)
+	}
+
+	if processGroup.exclusive {
+		pm.proxyLogger.Debugf("Exclusive mode for group %s, stopping other process groups", processGroup.id)
+		for groupId, otherGroup := range pm.processGroups {
+			if groupId != processGroup.id && !otherGroup.persistent {
+				otherGroup.StopProcesses()
+			}
+		}
+	}
+
+	return processGroup, realModelName, nil
+}
+
 func (pm *ProxyManager) listModelsHandler(c *gin.Context) {
 	data := []interface{}{}
 	for id, modelConfig := range pm.config.Models {
@@ -225,78 +294,6 @@ func (pm *ProxyManager) listModelsHandler(c *gin.Context) {
 	}
 }
 
-func (pm *ProxyManager) swapModel(requestedModel string) (*Process, error) {
-	pm.Lock()
-	defer pm.Unlock()
-
-	// Check if requestedModel contains a PROFILE_SPLIT_CHAR
-	profileName, modelName := splitRequestedModel(requestedModel)
-
-	if profileName != "" {
-		if _, found := pm.config.Profiles[profileName]; !found {
-			return nil, fmt.Errorf("model group not found %s", profileName)
-		}
-	}
-
-	// de-alias the real model name and get a real one
-	realModelName, found := pm.config.RealModelName(modelName)
-	if !found {
-		return nil, fmt.Errorf("could not find modelID for %s", requestedModel)
-	}
-
-	// check if model is part of the profile
-	if profileName != "" {
-		found := false
-		for _, item := range pm.config.Profiles[profileName] {
-			if item == realModelName {
-				found = true
-				break
-			}
-		}
-
-		if !found {
-			return nil, fmt.Errorf("model %s part of profile %s", realModelName, profileName)
-		}
-	}
-
-	// exit early when already running, otherwise stop everything and swap
-	requestedProcessKey := ProcessKeyName(profileName, realModelName)
-
-	if process, found := pm.currentProcesses[requestedProcessKey]; found {
-		return process, nil
-	}
-
-	// stop all running models
-	pm.stopProcesses()
-
-	if profileName == "" {
-		modelConfig, modelID, found := pm.config.FindConfig(realModelName)
-		if !found {
-			return nil, fmt.Errorf("could not find configuration for %s", realModelName)
-		}
-
-		process := NewProcess(modelID, pm.config.HealthCheckTimeout, modelConfig, pm.logMonitor)
-		processKey := ProcessKeyName(profileName, modelID)
-		pm.currentProcesses[processKey] = process
-	} else {
-		for _, modelName := range pm.config.Profiles[profileName] {
-			if realModelName, found := pm.config.RealModelName(modelName); found {
-				modelConfig, modelID, found := pm.config.FindConfig(realModelName)
-				if !found {
-					return nil, fmt.Errorf("could not find configuration for %s in group %s", realModelName, profileName)
-				}
-
-				process := NewProcess(modelID, pm.config.HealthCheckTimeout, modelConfig, pm.logMonitor)
-				processKey := ProcessKeyName(profileName, modelID)
-				pm.currentProcesses[processKey] = process
-			}
-		}
-	}
-
-	// requestedProcessKey should exist due to swap
-	return pm.currentProcesses[requestedProcessKey], nil
-}
-
 func (pm *ProxyManager) proxyToUpstream(c *gin.Context) {
 	requestedModel := c.Param("model_id")
 
@@ -305,13 +302,15 @@ func (pm *ProxyManager) proxyToUpstream(c *gin.Context) {
 		return
 	}
 
-	if process, err := pm.swapModel(requestedModel); err != nil {
-		pm.sendErrorResponse(c, http.StatusNotFound, fmt.Sprintf("unable to swap to model, %s", err.Error()))
-	} else {
-		// rewrite the path
-		c.Request.URL.Path = c.Param("upstreamPath")
-		process.ProxyRequest(c.Writer, c.Request)
+	processGroup, _, err := pm.swapProcessGroup(requestedModel)
+	if err != nil {
+		pm.sendErrorResponse(c, http.StatusInternalServerError, fmt.Sprintf("error swapping process group: %s", err.Error()))
+		return
 	}
+
+	// rewrite the path
+	c.Request.URL.Path = c.Param("upstreamPath")
+	processGroup.ProxyRequest(requestedModel, c.Writer, c.Request)
 }
 
 func (pm *ProxyManager) upstreamIndex(c *gin.Context) {
@@ -349,32 +348,23 @@ func (pm *ProxyManager) proxyOAIHandler(c *gin.Context) {
 	requestedModel := gjson.GetBytes(bodyBytes, "model").String()
 	if requestedModel == "" {
 		pm.sendErrorResponse(c, http.StatusBadRequest, "missing or invalid 'model' key")
+		return
 	}
 
-	process, err := pm.swapModel(requestedModel)
-
+	processGroup, realModelName, err := pm.swapProcessGroup(requestedModel)
 	if err != nil {
-		pm.sendErrorResponse(c, http.StatusNotFound, fmt.Sprintf("unable to swap to model, %s", err.Error()))
+		pm.sendErrorResponse(c, http.StatusInternalServerError, fmt.Sprintf("error swapping process group: %s", err.Error()))
 		return
 	}
 
 	// issue #69 allow custom model names to be sent to upstream
-	if process.config.UseModelName != "" {
-		bodyBytes, err = sjson.SetBytes(bodyBytes, "model", process.config.UseModelName)
+	useModelName := pm.config.Models[realModelName].UseModelName
+	if useModelName != "" {
+		bodyBytes, err = sjson.SetBytes(bodyBytes, "model", useModelName)
 		if err != nil {
-			pm.sendErrorResponse(c, http.StatusInternalServerError, fmt.Sprintf("error updating JSON: %s", err.Error()))
+			pm.sendErrorResponse(c, http.StatusInternalServerError, fmt.Sprintf("error rewriting model name in JSON: %s", err.Error()))
 			return
 		}
-	} else {
-		profileName, modelName := splitRequestedModel(requestedModel)
-		if profileName != "" {
-			bodyBytes, err = sjson.SetBytes(bodyBytes, "model", modelName)
-			if err != nil {
-				pm.sendErrorResponse(c, http.StatusInternalServerError, fmt.Sprintf("error updating JSON: %s", err.Error()))
-				return
-			}
-		}
-
 	}
 
 	c.Request.Body = io.NopCloser(bytes.NewBuffer(bodyBytes))
@@ -383,8 +373,11 @@ func (pm *ProxyManager) proxyOAIHandler(c *gin.Context) {
 	c.Request.Header.Del("transfer-encoding")
 	c.Request.Header.Add("content-length", strconv.Itoa(len(bodyBytes)))
 
-	process.ProxyRequest(c.Writer, c.Request)
-
+	if err := processGroup.ProxyRequest(realModelName, c.Writer, c.Request); err != nil {
+		pm.sendErrorResponse(c, http.StatusInternalServerError, fmt.Sprintf("error proxying request: %s", err.Error()))
+		pm.proxyLogger.Errorf("Error Proxying Request for processGroup %s and model %s", processGroup.id, realModelName)
+		return
+	}
 }
 
 func (pm *ProxyManager) proxyOAIPostFormHandler(c *gin.Context) {
@@ -406,26 +399,25 @@ func (pm *ProxyManager) proxyOAIPostFormHandler(c *gin.Context) {
 		return
 	}
 
-	// Swap to the requested model
-	process, err := pm.swapModel(requestedModel)
+	processGroup, realModelName, err := pm.swapProcessGroup(requestedModel)
 	if err != nil {
-		pm.sendErrorResponse(c, http.StatusNotFound, fmt.Sprintf("unable to swap to model, %s", err.Error()))
+		pm.sendErrorResponse(c, http.StatusInternalServerError, fmt.Sprintf("error swapping process group: %s", err.Error()))
 		return
 	}
 
-	// Get profile name and model name from the requested model
-	profileName, modelName := splitRequestedModel(requestedModel)
-
 	// Copy all form values
 	for key, values := range c.Request.MultipartForm.Value {
 		for _, value := range values {
 			fieldValue := value
 			// If this is the model field and we have a profile, use just the model name
 			if key == "model" {
-				if process.config.UseModelName != "" {
-					fieldValue = process.config.UseModelName
-				} else if profileName != "" {
-					fieldValue = modelName
+				// # issue #69 allow custom model names to be sent to upstream
+				useModelName := pm.config.Models[realModelName].UseModelName
+
+				if useModelName != "" {
+					fieldValue = useModelName
+				} else {
+					fieldValue = requestedModel
 				}
 			}
 			field, err := multipartWriter.CreateFormField(key)
@@ -487,7 +479,11 @@ func (pm *ProxyManager) proxyOAIPostFormHandler(c *gin.Context) {
 	modifiedReq.Header.Set("Content-Type", multipartWriter.FormDataContentType())
 
 	// Use the modified request for proxying
-	process.ProxyRequest(c.Writer, modifiedReq)
+	if err := processGroup.ProxyRequest(realModelName, c.Writer, modifiedReq); err != nil {
+		pm.sendErrorResponse(c, http.StatusInternalServerError, fmt.Sprintf("error proxying request: %s", err.Error()))
+		pm.proxyLogger.Errorf("Error Proxying Request for processGroup %s and model %s", processGroup.id, realModelName)
+		return
+	}
 }
 
 func (pm *ProxyManager) sendErrorResponse(c *gin.Context, statusCode int, message string) {
@@ -509,14 +505,15 @@ func (pm *ProxyManager) listRunningProcessesHandler(context *gin.Context) {
 	context.Header("Content-Type", "application/json")
 	runningProcesses := make([]gin.H, 0) // Default to an empty response.
 
-	for _, process := range pm.currentProcesses {
-
-		// Append the process ID and State (multiple entries if profiles are being used).
-		runningProcesses = append(runningProcesses, gin.H{
-			"model": process.ID,
-			"state": process.state,
-		})
-
+	for _, processGroup := range pm.processGroups {
+		for _, process := range processGroup.processes {
+			if process.CurrentState() == StateReady {
+				runningProcesses = append(runningProcesses, gin.H{
+					"model": process.ID,
+					"state": process.state,
+				})
+			}
+		}
 	}
 
 	// Put the results under the `running` key.
@@ -527,15 +524,11 @@ func (pm *ProxyManager) listRunningProcessesHandler(context *gin.Context) {
 	context.JSON(http.StatusOK, response) // Always return 200 OK
 }
 
-func ProcessKeyName(groupName, modelName string) string {
-	return groupName + PROFILE_SPLIT_CHAR + modelName
-}
-
-func splitRequestedModel(requestedModel string) (string, string) {
-	profileName, modelName := "", requestedModel
-	if idx := strings.Index(requestedModel, PROFILE_SPLIT_CHAR); idx != -1 {
-		profileName = requestedModel[:idx]
-		modelName = requestedModel[idx+1:]
+func (pm *ProxyManager) findGroupByModelName(modelName string) *ProcessGroup {
+	for _, group := range pm.processGroups {
+		if group.HasMember(modelName) {
+			return group
+		}
 	}
-	return profileName, modelName
+	return nil
 }

proxy/proxymanager_loghandlers.go

@@ -9,7 +9,6 @@ import (
 )
 
 func (pm *ProxyManager) sendLogsHandlers(c *gin.Context) {
-
 	accept := c.GetHeader("Accept")
 	if strings.Contains(accept, "text/html") {
 		// Set the Content-Type header to text/html
@@ -28,7 +27,7 @@ func (pm *ProxyManager) sendLogsHandlers(c *gin.Context) {
 		}
 	} else {
 		c.Header("Content-Type", "text/plain")
-		history := pm.logMonitor.GetHistory()
+		history := pm.muxLogger.GetHistory()
 		_, err := c.Writer.Write(history)
 		if err != nil {
 			c.AbortWithError(http.StatusInternalServerError, err)
@@ -42,8 +41,14 @@ func (pm *ProxyManager) streamLogsHandler(c *gin.Context) {
 	c.Header("Transfer-Encoding", "chunked")
 	c.Header("X-Content-Type-Options", "nosniff")
 
-	ch := pm.logMonitor.Subscribe()
-	defer pm.logMonitor.Unsubscribe(ch)
+	logMonitorId := c.Param("logMonitorID")
+	logger, err := pm.getLogger(logMonitorId)
+	if err != nil {
+		c.String(http.StatusBadRequest, err.Error())
+		return
+	}
+	ch := logger.Subscribe()
+	defer logger.Unsubscribe(ch)
 
 	notify := c.Request.Context().Done()
 	flusher, ok := c.Writer.(http.Flusher)
@@ -56,7 +61,7 @@ func (pm *ProxyManager) streamLogsHandler(c *gin.Context) {
 	// Send history first if not skipped
 
 	if !skipHistory {
-		history := pm.logMonitor.GetHistory()
+		history := logger.GetHistory()
 		if len(history) != 0 {
 			c.Writer.Write(history)
 			flusher.Flush()
@@ -85,15 +90,21 @@ func (pm *ProxyManager) streamLogsHandlerSSE(c *gin.Context) {
 	c.Header("Connection", "keep-alive")
 	c.Header("X-Content-Type-Options", "nosniff")
 
-	ch := pm.logMonitor.Subscribe()
-	defer pm.logMonitor.Unsubscribe(ch)
+	logMonitorId := c.Param("logMonitorID")
+	logger, err := pm.getLogger(logMonitorId)
+	if err != nil {
+		c.String(http.StatusBadRequest, err.Error())
+		return
+	}
+	ch := logger.Subscribe()
+	defer logger.Unsubscribe(ch)
 
 	notify := c.Request.Context().Done()
 
 	// Send history first if not skipped
 	_, skipHistory := c.GetQuery("no-history")
 	if !skipHistory {
-		history := pm.logMonitor.GetHistory()
+		history := logger.GetHistory()
 		if len(history) != 0 {
 			c.SSEvent("message", string(history))
 			c.Writer.Flush()
@@ -111,3 +122,21 @@ func (pm *ProxyManager) streamLogsHandlerSSE(c *gin.Context) {
 		}
 	}
 }
+
+// getLogger searches for the appropriate logger based on the logMonitorId
+func (pm *ProxyManager) getLogger(logMonitorId string) (*LogMonitor, error) {
+	var logger *LogMonitor
+
+	if logMonitorId == "" {
+		// maintain the default
+		logger = pm.muxLogger
+	} else if logMonitorId == "proxy" {
+		logger = pm.proxyLogger
+	} else if logMonitorId == "upstream" {
+		logger = pm.upstreamLogger
+	} else {
+		return nil, fmt.Errorf("invalid logger. Use 'proxy' or 'upstream'")
+	}
+
+	return logger, nil
+}

proxy/proxymanager_test.go

@@ -16,13 +16,14 @@ import (
 )
 
 func TestProxyManager_SwapProcessCorrectly(t *testing.T) {
-	config := &Config{
+	config := AddDefaultGroupToConfig(Config{
 		HealthCheckTimeout: 15,
 		Models: map[string]ModelConfig{
 			"model1": getTestSimpleResponderConfig("model1"),
 			"model2": getTestSimpleResponderConfig("model2"),
 		},
-	}
+		LogLevel: "error",
+	})
 
 	proxy := New(config)
 	defer proxy.StopProcesses()
@@ -35,58 +36,91 @@ func TestProxyManager_SwapProcessCorrectly(t *testing.T) {
 		proxy.HandlerFunc(w, req)
 		assert.Equal(t, http.StatusOK, w.Code)
 		assert.Contains(t, w.Body.String(), modelName)
-
-		_, exists := proxy.currentProcesses[ProcessKeyName("", modelName)]
-		assert.True(t, exists, "expected %s key in currentProcesses", modelName)
-
 	}
-
-	// make sure there's only one loaded model
-	assert.Len(t, proxy.currentProcesses, 1)
 }
 
 func TestProxyManager_SwapMultiProcess(t *testing.T) {
-
-	model1 := "path1/model1"
-	model2 := "path2/model2"
-
-	profileModel1 := ProcessKeyName("test", model1)
-	profileModel2 := ProcessKeyName("test", model2)
-
-	config := &Config{
+	config := AddDefaultGroupToConfig(Config{
 		HealthCheckTimeout: 15,
 		Models: map[string]ModelConfig{
-			model1: getTestSimpleResponderConfig("model1"),
-			model2: getTestSimpleResponderConfig("model2"),
+			"model1": getTestSimpleResponderConfig("model1"),
+			"model2": getTestSimpleResponderConfig("model2"),
 		},
-		Profiles: map[string][]string{
-			"test": {model1, model2},
+		LogLevel: "error",
+		Groups: map[string]GroupConfig{
+			"G1": {
+				Swap:      true,
+				Exclusive: false,
+				Members:   []string{"model1"},
+			},
+			"G2": {
+				Swap:      true,
+				Exclusive: false,
+				Members:   []string{"model2"},
+			},
 		},
-	}
+	})
 
 	proxy := New(config)
 	defer proxy.StopProcesses()
 
-	for modelID, requestedModel := range map[string]string{
-		"model1": profileModel1,
-		"model2": profileModel2,
-	} {
+	tests := []string{"model1", "model2"}
+	for _, requestedModel := range tests {
+		t.Run(requestedModel, func(t *testing.T) {
+			reqBody := fmt.Sprintf(`{"model":"%s"}`, requestedModel)
+			req := httptest.NewRequest("POST", "/v1/chat/completions", bytes.NewBufferString(reqBody))
+			w := httptest.NewRecorder()
+
+			proxy.HandlerFunc(w, req)
+			assert.Equal(t, http.StatusOK, w.Code)
+			assert.Contains(t, w.Body.String(), requestedModel)
+
+		})
+	}
+
+	// make sure there's two loaded models
+	assert.Equal(t, proxy.findGroupByModelName("model1").processes["model1"].CurrentState(), StateReady)
+	assert.Equal(t, proxy.findGroupByModelName("model2").processes["model2"].CurrentState(), StateReady)
+}
+
+// Test that a persistent group is not affected by the swapping behaviour of
+// other groups.
+func TestProxyManager_PersistentGroupsAreNotSwapped(t *testing.T) {
+	config := AddDefaultGroupToConfig(Config{
+		HealthCheckTimeout: 15,
+		Models: map[string]ModelConfig{
+			"model1": getTestSimpleResponderConfig("model1"), // goes into the default group
+			"model2": getTestSimpleResponderConfig("model2"),
+		},
+		LogLevel: "error",
+		Groups: map[string]GroupConfig{
+			// the forever group is persistent and should not be affected by model1
+			"forever": {
+				Swap:       true,
+				Exclusive:  false,
+				Persistent: true,
+				Members:    []string{"model2"},
+			},
+		},
+	})
+
+	proxy := New(config)
+	defer proxy.StopProcesses()
+
+	// make requests to load all models, loading model1 should not affect model2
+	tests := []string{"model2", "model1"}
+	for _, requestedModel := range tests {
 		reqBody := fmt.Sprintf(`{"model":"%s"}`, requestedModel)
 		req := httptest.NewRequest("POST", "/v1/chat/completions", bytes.NewBufferString(reqBody))
 		w := httptest.NewRecorder()
 
 		proxy.HandlerFunc(w, req)
 		assert.Equal(t, http.StatusOK, w.Code)
-		assert.Contains(t, w.Body.String(), modelID)
+		assert.Contains(t, w.Body.String(), requestedModel)
 	}
 
-	// make sure there's two loaded models
-	assert.Len(t, proxy.currentProcesses, 2)
-	_, exists := proxy.currentProcesses[profileModel1]
-	assert.True(t, exists, "expected "+profileModel1+" key in currentProcesses")
-
-	_, exists = proxy.currentProcesses[profileModel2]
-	assert.True(t, exists, "expected "+profileModel2+" key in currentProcesses")
+	assert.Equal(t, proxy.findGroupByModelName("model2").processes["model2"].CurrentState(), StateReady)
+	assert.Equal(t, proxy.findGroupByModelName("model1").processes["model1"].CurrentState(), StateReady)
 }
 
 // When a request for a different model comes in ProxyManager should wait until
@@ -96,14 +130,15 @@ func TestProxyManager_SwapMultiProcessParallelRequests(t *testing.T) {
 		t.Skip("skipping slow test")
 	}
 
-	config := &Config{
+	config := AddDefaultGroupToConfig(Config{
 		HealthCheckTimeout: 15,
 		Models: map[string]ModelConfig{
 			"model1": getTestSimpleResponderConfig("model1"),
 			"model2": getTestSimpleResponderConfig("model2"),
 			"model3": getTestSimpleResponderConfig("model3"),
 		},
-	}
+		LogLevel: "error",
+	})
 
 	proxy := New(config)
 	defer proxy.StopProcesses()
@@ -146,13 +181,14 @@ func TestProxyManager_SwapMultiProcessParallelRequests(t *testing.T) {
 }
 
 func TestProxyManager_ListModelsHandler(t *testing.T) {
-	config := &Config{
+	config := Config{
 		HealthCheckTimeout: 15,
 		Models: map[string]ModelConfig{
 			"model1": getTestSimpleResponderConfig("model1"),
 			"model2": getTestSimpleResponderConfig("model2"),
 			"model3": getTestSimpleResponderConfig("model3"),
 		},
+		LogLevel: "error",
 	}
 
 	proxy := New(config)
@@ -213,50 +249,6 @@ func TestProxyManager_ListModelsHandler(t *testing.T) {
 	assert.Empty(t, expectedModels, "not all expected models were returned")
 }
 
-func TestProxyManager_ProfileNonMember(t *testing.T) {
-
-	model1 := "path1/model1"
-	model2 := "path2/model2"
-
-	profileMemberName := ProcessKeyName("test", model1)
-	profileNonMemberName := ProcessKeyName("test", model2)
-
-	config := &Config{
-		HealthCheckTimeout: 15,
-		Models: map[string]ModelConfig{
-			model1: getTestSimpleResponderConfig("model1"),
-			model2: getTestSimpleResponderConfig("model2"),
-		},
-		Profiles: map[string][]string{
-			"test": {model1},
-		},
-	}
-
-	proxy := New(config)
-	defer proxy.StopProcesses()
-
-	// actual member of profile
-	{
-		reqBody := fmt.Sprintf(`{"model":"%s"}`, profileMemberName)
-		req := httptest.NewRequest("POST", "/v1/chat/completions", bytes.NewBufferString(reqBody))
-		w := httptest.NewRecorder()
-
-		proxy.HandlerFunc(w, req)
-		assert.Equal(t, http.StatusOK, w.Code)
-		assert.Contains(t, w.Body.String(), "model1")
-	}
-
-	// actual model, but non-member will 404
-	{
-		reqBody := fmt.Sprintf(`{"model":"%s"}`, profileNonMemberName)
-		req := httptest.NewRequest("POST", "/v1/chat/completions", bytes.NewBufferString(reqBody))
-		w := httptest.NewRecorder()
-
-		proxy.HandlerFunc(w, req)
-		assert.Equal(t, http.StatusNotFound, w.Code)
-	}
-}
-
 func TestProxyManager_Shutdown(t *testing.T) {
 	// make broken model configurations
 	model1Config := getTestSimpleResponderConfigPort("model1", 9991)
@@ -268,23 +260,27 @@ func TestProxyManager_Shutdown(t *testing.T) {
 	model3Config := getTestSimpleResponderConfigPort("model3", 9993)
 	model3Config.Proxy = "http://localhost:10003/"
 
-	config := &Config{
+	config := AddDefaultGroupToConfig(Config{
 		HealthCheckTimeout: 15,
-		Profiles: map[string][]string{
-			"test": {"model1", "model2", "model3"},
-		},
 		Models: map[string]ModelConfig{
 			"model1": model1Config,
 			"model2": model2Config,
 			"model3": model3Config,
 		},
-	}
+		LogLevel: "error",
+		Groups: map[string]GroupConfig{
+			"test": {
+				Swap:    false,
+				Members: []string{"model1", "model2", "model3"},
+			},
+		},
+	})
 
 	proxy := New(config)
 
 	// Start all the processes
 	var wg sync.WaitGroup
-	for _, modelName := range []string{"test:model1", "test:model2", "test:model3"} {
+	for _, modelName := range []string{"model1", "model2", "model3"} {
 		wg.Add(1)
 		go func(modelName string) {
 			defer wg.Done()
@@ -292,11 +288,10 @@ func TestProxyManager_Shutdown(t *testing.T) {
 			req := httptest.NewRequest("POST", "/v1/chat/completions", bytes.NewBufferString(reqBody))
 			w := httptest.NewRecorder()
 
-			// send a request to trigger the proxy to load
+			// send a request to trigger the proxy to load ... this should hang waiting for start up
 			proxy.HandlerFunc(w, req)
 			assert.Equal(t, http.StatusBadGateway, w.Code)
 			assert.Contains(t, w.Body.String(), "health check interrupted due to shutdown")
-			//fmt.Println(w.Code, w.Body.String())
 		}(modelName)
 	}
 
@@ -308,64 +303,44 @@ func TestProxyManager_Shutdown(t *testing.T) {
 }
 
 func TestProxyManager_Unload(t *testing.T) {
-	config := &Config{
+	config := AddDefaultGroupToConfig(Config{
 		HealthCheckTimeout: 15,
 		Models: map[string]ModelConfig{
 			"model1": getTestSimpleResponderConfig("model1"),
 		},
-	}
+		LogLevel: "error",
+	})
 
 	proxy := New(config)
-	proc, err := proxy.swapModel("model1")
-	assert.NoError(t, err)
-	assert.NotNil(t, proc)
-
-	assert.Len(t, proxy.currentProcesses, 1)
-	req := httptest.NewRequest("GET", "/unload", nil)
+	reqBody := fmt.Sprintf(`{"model":"%s"}`, "model1")
+	req := httptest.NewRequest("POST", "/v1/chat/completions", bytes.NewBufferString(reqBody))
 	w := httptest.NewRecorder()
 	proxy.HandlerFunc(w, req)
+
+	assert.Equal(t, proxy.processGroups[DEFAULT_GROUP_ID].processes["model1"].CurrentState(), StateReady)
+	req = httptest.NewRequest("GET", "/unload", nil)
+	w = httptest.NewRecorder()
+	proxy.HandlerFunc(w, req)
 	assert.Equal(t, http.StatusOK, w.Code)
 	assert.Equal(t, w.Body.String(), "OK")
-	assert.Len(t, proxy.currentProcesses, 0)
-}
 
-// issue 62, strip profile slug from model name
-func TestProxyManager_StripProfileSlug(t *testing.T) {
-	config := &Config{
-		HealthCheckTimeout: 15,
-		Profiles: map[string][]string{
-			"test": {"TheExpectedModel"}, // TheExpectedModel is default in simple-responder.go
-		},
-		Models: map[string]ModelConfig{
-			"TheExpectedModel": getTestSimpleResponderConfig("TheExpectedModel"),
-		},
-	}
-
-	proxy := New(config)
-	defer proxy.StopProcesses()
-
-	reqBody := fmt.Sprintf(`{"model":"%s"}`, "test:TheExpectedModel")
-	req := httptest.NewRequest("POST", "/v1/audio/speech", bytes.NewBufferString(reqBody))
-	w := httptest.NewRecorder()
-	proxy.HandlerFunc(w, req)
-	assert.Equal(t, http.StatusOK, w.Code)
-	assert.Contains(t, w.Body.String(), "ok")
+	// give it a bit of time to stop
+	<-time.After(time.Millisecond * 250)
+	assert.Equal(t, proxy.processGroups[DEFAULT_GROUP_ID].processes["model1"].CurrentState(), StateStopped)
 }
 
 // Test issue #61 `Listing the current list of models and the loaded model.`
 func TestProxyManager_RunningEndpoint(t *testing.T) {
 
 	// Shared configuration
-	config := &Config{
+	config := AddDefaultGroupToConfig(Config{
 		HealthCheckTimeout: 15,
 		Models: map[string]ModelConfig{
 			"model1": getTestSimpleResponderConfig("model1"),
 			"model2": getTestSimpleResponderConfig("model2"),
 		},
-		Profiles: map[string][]string{
-			"test": {"model1", "model2"},
-		},
-	}
+		LogLevel: "debug",
+	})
 
 	// Define a helper struct to parse the JSON response.
 	type RunningResponse struct {
@@ -420,224 +395,200 @@ func TestProxyManager_RunningEndpoint(t *testing.T) {
 		// Is the model loaded?
 		assert.Equal(t, "ready", response.Running[0].State)
 	})
-
-	t.Run("multiple models via profile", func(t *testing.T) {
-		// Load more than one model.
-		for _, model := range []string{"model1", "model2"} {
-			profileModel := ProcessKeyName("test", model)
-			reqBody := fmt.Sprintf(`{"model":"%s"}`, profileModel)
-			req := httptest.NewRequest("POST", "/v1/chat/completions", bytes.NewBufferString(reqBody))
-			w := httptest.NewRecorder()
-			proxy.HandlerFunc(w, req)
-			assert.Equal(t, http.StatusOK, w.Code)
-		}
-
-		// Simulate the browser call.
-		req := httptest.NewRequest("GET", "/running", nil)
-		w := httptest.NewRecorder()
-		proxy.HandlerFunc(w, req)
-
-		var response RunningResponse
-
-		// The JSON response must be valid.
-		assert.NoError(t, json.Unmarshal(w.Body.Bytes(), &response))
-
-		// The response should contain 2 models.
-		assert.Len(t, response.Running, 2)
-
-		expectedModels := map[string]struct{}{
-			"model1": {},
-			"model2": {},
-		}
-
-		// Iterate through the models and check their states as well.
-		for _, entry := range response.Running {
-			_, exists := expectedModels[entry.Model]
-			assert.True(t, exists, "unexpected model %s", entry.Model)
-			assert.Equal(t, "ready", entry.State)
-			delete(expectedModels, entry.Model)
-		}
-
-		// Since we deleted each model while testing for its validity we should have no more models in the response.
-		assert.Empty(t, expectedModels, "unexpected additional models in response")
-	})
 }
 
 func TestProxyManager_AudioTranscriptionHandler(t *testing.T) {
-	config := &Config{
+	config := AddDefaultGroupToConfig(Config{
 		HealthCheckTimeout: 15,
-		Profiles: map[string][]string{
-			"test": {"TheExpectedModel"},
-		},
 		Models: map[string]ModelConfig{
 			"TheExpectedModel": getTestSimpleResponderConfig("TheExpectedModel"),
 		},
-	}
+		LogLevel: "error",
+	})
 
 	proxy := New(config)
 	defer proxy.StopProcesses()
 
-	testCases := []struct {
-		name        string
-		modelInput  string
-		expectModel string
-	}{
-		{
-			name:        "With Profile Prefix",
-			modelInput:  "test:TheExpectedModel",
-			expectModel: "TheExpectedModel", // Profile prefix should be stripped
-		},
-		{
-			name:        "Without Profile Prefix",
-			modelInput:  "TheExpectedModel",
-			expectModel: "TheExpectedModel", // Should remain the same
-		},
-	}
+	// Create a buffer with multipart form data
+	var b bytes.Buffer
+	w := multipart.NewWriter(&b)
 
-	for _, tc := range testCases {
-		t.Run(tc.name, func(t *testing.T) {
-			// Create a buffer with multipart form data
-			var b bytes.Buffer
-			w := multipart.NewWriter(&b)
+	// Add the model field
+	fw, err := w.CreateFormField("model")
+	assert.NoError(t, err)
+	_, err = fw.Write([]byte("TheExpectedModel"))
+	assert.NoError(t, err)
 
-			// Add the model field
-			fw, err := w.CreateFormField("model")
-			assert.NoError(t, err)
-			_, err = fw.Write([]byte(tc.modelInput))
-			assert.NoError(t, err)
+	// Add a file field
+	fw, err = w.CreateFormFile("file", "test.mp3")
+	assert.NoError(t, err)
+	// Generate random content length between 10 and 20
+	contentLength := rand.Intn(11) + 10 // 10 to 20
+	content := make([]byte, contentLength)
+	_, err = fw.Write(content)
+	assert.NoError(t, err)
+	w.Close()
 
-			// Add a file field
-			fw, err = w.CreateFormFile("file", "test.mp3")
-			assert.NoError(t, err)
-			// Generate random content length between 10 and 20
-			contentLength := rand.Intn(11) + 10 // 10 to 20
-			content := make([]byte, contentLength)
-			_, err = fw.Write(content)
-			assert.NoError(t, err)
-			w.Close()
+	// Create the request with the multipart form data
+	req := httptest.NewRequest("POST", "/v1/audio/transcriptions", &b)
+	req.Header.Set("Content-Type", w.FormDataContentType())
+	rec := httptest.NewRecorder()
+	proxy.HandlerFunc(rec, req)
 
-			// Create the request with the multipart form data
-			req := httptest.NewRequest("POST", "/v1/audio/transcriptions", &b)
-			req.Header.Set("Content-Type", w.FormDataContentType())
-			rec := httptest.NewRecorder()
-			proxy.HandlerFunc(rec, req)
-
-			// Verify the response
-			assert.Equal(t, http.StatusOK, rec.Code)
-			var response map[string]string
-			err = json.Unmarshal(rec.Body.Bytes(), &response)
-			assert.NoError(t, err)
-			assert.Equal(t, tc.expectModel, response["model"])
-			assert.Equal(t, response["text"], fmt.Sprintf("The length of the file is %d bytes", contentLength)) // matches simple-responder
-		})
-	}
-}
-
-func TestProxyManager_SplitRequestedModel(t *testing.T) {
-
-	tests := []struct {
-		name            string
-		requestedModel  string
-		expectedProfile string
-		expectedModel   string
-	}{
-		{"no profile", "gpt-4", "", "gpt-4"},
-		{"with profile", "profile1:gpt-4", "profile1", "gpt-4"},
-		{"only profile", "profile1:", "profile1", ""},
-		{"empty model", ":gpt-4", "", "gpt-4"},
-		{"empty profile", ":", "", ""},
-		{"no split char", "gpt-4", "", "gpt-4"},
-		{"profile and model with delimiter", "profile1:delimiter:gpt-4", "profile1", "delimiter:gpt-4"},
-	}
-
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			profileName, modelName := splitRequestedModel(tt.requestedModel)
-			if profileName != tt.expectedProfile {
-				t.Errorf("splitRequestedModel(%q) = %q, %q; want %q, %q", tt.requestedModel, profileName, modelName, tt.expectedProfile, tt.expectedModel)
-			}
-			if modelName != tt.expectedModel {
-				t.Errorf("splitRequestedModel(%q) = %q, %q; want %q, %q", tt.requestedModel, profileName, modelName, tt.expectedProfile, tt.expectedModel)
-			}
-		})
-	}
+	// Verify the response
+	assert.Equal(t, http.StatusOK, rec.Code)
+	var response map[string]string
+	err = json.Unmarshal(rec.Body.Bytes(), &response)
+	assert.NoError(t, err)
+	assert.Equal(t, "TheExpectedModel", response["model"])
+	assert.Equal(t, response["text"], fmt.Sprintf("The length of the file is %d bytes", contentLength)) // matches simple-responder
 }
 
 // Test useModelName in configuration sends overrides what is sent to upstream
 func TestProxyManager_UseModelName(t *testing.T) {
-
 	upstreamModelName := "upstreamModel"
 
 	modelConfig := getTestSimpleResponderConfig(upstreamModelName)
 	modelConfig.UseModelName = upstreamModelName
 
-	config := &Config{
+	config := AddDefaultGroupToConfig(Config{
 		HealthCheckTimeout: 15,
-		Profiles: map[string][]string{
-			"test": {"model1"},
-		},
-
 		Models: map[string]ModelConfig{
 			"model1": modelConfig,
 		},
-	}
+		LogLevel: "error",
+	})
 
 	proxy := New(config)
 	defer proxy.StopProcesses()
 
-	tests := []struct {
-		description    string
-		requestedModel string
-	}{
-		{"useModelName over rides requested model", "model1"},
-		{"useModelName over rides requested profile:model", "test:model1"},
-	}
+	requestedModel := "model1"
 
-	for _, tt := range tests {
-		t.Run(tt.description+": /v1/chat/completions", func(t *testing.T) {
-			reqBody := fmt.Sprintf(`{"model":"%s"}`, tt.requestedModel)
-			req := httptest.NewRequest("POST", "/v1/chat/completions", bytes.NewBufferString(reqBody))
-			w := httptest.NewRecorder()
+	t.Run("useModelName over rides requested model: /v1/chat/completions", func(t *testing.T) {
+		reqBody := fmt.Sprintf(`{"model":"%s"}`, requestedModel)
+		req := httptest.NewRequest("POST", "/v1/chat/completions", bytes.NewBufferString(reqBody))
+		w := httptest.NewRecorder()
 
-			proxy.HandlerFunc(w, req)
-			assert.Equal(t, http.StatusOK, w.Code)
-			assert.Contains(t, w.Body.String(), upstreamModelName)
+		proxy.HandlerFunc(w, req)
+		assert.Equal(t, http.StatusOK, w.Code)
+		assert.Contains(t, w.Body.String(), upstreamModelName)
+	})
 
-		})
-	}
+	t.Run("useModelName over rides requested model: /v1/audio/transcriptions", func(t *testing.T) {
+		// Create a buffer with multipart form data
+		var b bytes.Buffer
+		w := multipart.NewWriter(&b)
 
-	for _, tt := range tests {
-		t.Run(tt.description+": /v1/audio/transcriptions", func(t *testing.T) {
-			// Create a buffer with multipart form data
-			var b bytes.Buffer
-			w := multipart.NewWriter(&b)
+		// Add the model field
+		fw, err := w.CreateFormField("model")
+		assert.NoError(t, err)
+		_, err = fw.Write([]byte(requestedModel))
+		assert.NoError(t, err)
 
-			// Add the model field
-			fw, err := w.CreateFormField("model")
-			assert.NoError(t, err)
-			_, err = fw.Write([]byte(tt.requestedModel))
-			assert.NoError(t, err)
+		// Add a file field
+		fw, err = w.CreateFormFile("file", "test.mp3")
+		assert.NoError(t, err)
+		_, err = fw.Write([]byte("test"))
+		assert.NoError(t, err)
+		w.Close()
 
-			// Add a file field
-			fw, err = w.CreateFormFile("file", "test.mp3")
-			assert.NoError(t, err)
-			_, err = fw.Write([]byte("test"))
-			assert.NoError(t, err)
-			w.Close()
-
-			// Create the request with the multipart form data
-			req := httptest.NewRequest("POST", "/v1/audio/transcriptions", &b)
-			req.Header.Set("Content-Type", w.FormDataContentType())
-			rec := httptest.NewRecorder()
-			proxy.HandlerFunc(rec, req)
-
-			// Verify the response
-			assert.Equal(t, http.StatusOK, rec.Code)
-			var response map[string]string
-			err = json.Unmarshal(rec.Body.Bytes(), &response)
-			assert.NoError(t, err)
-			assert.Equal(t, upstreamModelName, response["model"])
-		})
-	}
+		// Create the request with the multipart form data
+		req := httptest.NewRequest("POST", "/v1/audio/transcriptions", &b)
+		req.Header.Set("Content-Type", w.FormDataContentType())
+		rec := httptest.NewRecorder()
+		proxy.HandlerFunc(rec, req)
 
+		// Verify the response
+		assert.Equal(t, http.StatusOK, rec.Code)
+		var response map[string]string
+		err = json.Unmarshal(rec.Body.Bytes(), &response)
+		assert.NoError(t, err)
+		assert.Equal(t, upstreamModelName, response["model"])
+	})
+}
+
+func TestProxyManager_CORSOptionsHandler(t *testing.T) {
+	config := AddDefaultGroupToConfig(Config{
+		HealthCheckTimeout: 15,
+		Models: map[string]ModelConfig{
+			"model1": getTestSimpleResponderConfig("model1"),
+		},
+		LogLevel: "error",
+	})
+
+	tests := []struct {
+		name            string
+		method          string
+		requestHeaders  map[string]string
+		expectedStatus  int
+		expectedHeaders map[string]string
+	}{
+		{
+			name:           "OPTIONS with no headers",
+			method:         "OPTIONS",
+			expectedStatus: http.StatusNoContent,
+			expectedHeaders: map[string]string{
+				"Access-Control-Allow-Origin":  "*",
+				"Access-Control-Allow-Methods": "GET, POST, PUT, PATCH, DELETE, OPTIONS",
+				"Access-Control-Allow-Headers": "Content-Type, Authorization, Accept, X-Requested-With",
+			},
+		},
+		{
+			name:   "OPTIONS with specific headers",
+			method: "OPTIONS",
+			requestHeaders: map[string]string{
+				"Access-Control-Request-Headers": "X-Custom-Header, Some-Other-Header",
+			},
+			expectedStatus: http.StatusNoContent,
+			expectedHeaders: map[string]string{
+				"Access-Control-Allow-Origin":  "*",
+				"Access-Control-Allow-Methods": "GET, POST, PUT, PATCH, DELETE, OPTIONS",
+				"Access-Control-Allow-Headers": "X-Custom-Header, Some-Other-Header",
+			},
+		},
+		{
+			name:           "Non-OPTIONS request",
+			method:         "GET",
+			expectedStatus: http.StatusNotFound, // Since we don't have a GET route defined
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			proxy := New(config)
+			defer proxy.StopProcesses()
+
+			req := httptest.NewRequest(tt.method, "/v1/chat/completions", nil)
+			for k, v := range tt.requestHeaders {
+				req.Header.Set(k, v)
+			}
+
+			w := httptest.NewRecorder()
+			proxy.ginEngine.ServeHTTP(w, req)
+
+			assert.Equal(t, tt.expectedStatus, w.Code)
+
+			for header, expectedValue := range tt.expectedHeaders {
+				assert.Equal(t, expectedValue, w.Header().Get(header))
+			}
+		})
+	}
+}
+
+func TestProxyManager_Upstream(t *testing.T) {
+	config := AddDefaultGroupToConfig(Config{
+		HealthCheckTimeout: 15,
+		Models: map[string]ModelConfig{
+			"model1": getTestSimpleResponderConfig("model1"),
+		},
+		LogLevel: "error",
+	})
+
+	proxy := New(config)
+	defer proxy.StopProcesses()
+	req := httptest.NewRequest("GET", "/upstream/model1/test", nil)
+	rec := httptest.NewRecorder()
+	proxy.HandlerFunc(rec, req)
+	assert.Equal(t, http.StatusOK, rec.Code)
+	assert.Equal(t, "model1", rec.Body.String())
 }

proxy/sanitize_cors.go

@@ -0,0 +1,43 @@
+package proxy
+
+import (
+	"strings"
+)
+
+func isTokenChar(r rune) bool {
+	switch {
+	case r >= 'a' && r <= 'z':
+	case r >= 'A' && r <= 'Z':
+	case r >= '0' && r <= '9':
+	case strings.ContainsRune("!#$%&'*+-.^_`|~", r):
+	default:
+		return false
+	}
+	return true
+}
+
+func SanitizeAccessControlRequestHeaderValues(headerValues string) string {
+	parts := strings.Split(headerValues, ",")
+	valid := make([]string, 0, len(parts))
+
+	for _, p := range parts {
+		v := strings.TrimSpace(p)
+		if v == "" {
+			continue
+		}
+
+		validPart := true
+		for _, c := range v {
+			if !isTokenChar(c) {
+				validPart = false
+				break
+			}
+		}
+
+		if validPart {
+			valid = append(valid, v)
+		}
+	}
+
+	return strings.Join(valid, ", ")
+}

proxy/sanitize_cors_test.go

@@ -0,0 +1,77 @@
+package proxy
+
+import "testing"
+
+func TestSanitizeAccessControlRequestHeaderValues(t *testing.T) {
+	tests := []struct {
+		name     string
+		input    string
+		expected string
+	}{
+		{
+			name:     "empty string",
+			input:    "",
+			expected: "",
+		},
+		{
+			name:     "whitespace only",
+			input:    "   ",
+			expected: "",
+		},
+		{
+			name:     "single valid value",
+			input:    "content-type",
+			expected: "content-type",
+		},
+		{
+			name:     "multiple valid values",
+			input:    "content-type, authorization, x-requested-with",
+			expected: "content-type, authorization, x-requested-with",
+		},
+		{
+			name:     "values with extra spaces",
+			input:    "  content-type  ,  authorization  ",
+			expected: "content-type, authorization",
+		},
+		{
+			name:     "values with tabs",
+			input:    "content-type,\tauthorization",
+			expected: "content-type, authorization",
+		},
+		{
+			name:     "values with invalid characters",
+			input:    "content-type, auth\n, x-requested-with\r",
+			expected: "content-type, auth, x-requested-with",
+		},
+		{
+			name:     "empty values in list",
+			input:    "content-type,,authorization",
+			expected: "content-type, authorization",
+		},
+		{
+			name:     "leading and trailing commas",
+			input:    ",content-type,authorization,",
+			expected: "content-type, authorization",
+		},
+		{
+			name:     "mixed valid and invalid values",
+			input:    "content-type, \x00invalid, x-requested-with",
+			expected: "content-type, x-requested-with",
+		},
+		{
+			name:     "mixed case values",
+			input:    "Content-Type, my-Valid-Header, Another-hEader",
+			expected: "Content-Type, my-Valid-Header, Another-hEader",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := SanitizeAccessControlRequestHeaderValues(tt.input)
+			if got != tt.expected {
+				t.Errorf("SanitizeAccessControlRequestHeaderValues(%q) = %q, want %q",
+					tt.input, got, tt.expected)
+			}
+		})
+	}
+}