proxy: implement setParamsByID filter (#535)

Add setParamsByID filter that applies different request parameters based on the requested model ID, enabling per-alias behaviour for a single loaded model. - add SetParamsByID field to Filters struct and SanitizedSetParamsByID method - substitute ${MODEL_ID} and other macros in setParamsByID keys and values - validate no unknown macros remain in keys or values after substitution - apply setParamsByID in proxyInferenceHandler after setParams (can override it) - update config-schema.json with setParamsByID definition - update UI to show aliases and make them selectable in the Playground closes #534
2026-02-19 22:21:10 -08:00
parent b45102bde8
commit 19fb5f35e9
12 changed files with 387 additions and 20 deletions
@@ -294,6 +294,24 @@ func LoadConfigFromReader(r io.Reader) (Config, error) {
 			modelConfig.CheckEndpoint = strings.ReplaceAll(modelConfig.CheckEndpoint, macroSlug, macroStr)
 			modelConfig.Filters.StripParams = strings.ReplaceAll(modelConfig.Filters.StripParams, macroSlug, macroStr)

+			// Substitute macros in SetParamsByID keys and values
+			if len(modelConfig.Filters.SetParamsByID) > 0 {
+				newSetParamsByID := make(map[string]map[string]any, len(modelConfig.Filters.SetParamsByID))
+				for key, paramMap := range modelConfig.Filters.SetParamsByID {
+					newKey := strings.ReplaceAll(key, macroSlug, macroStr)
+					newValAny, err := substituteMacroInValue(any(paramMap), entry.Name, entry.Value)
+					if err != nil {
+						return Config{}, fmt.Errorf("model %s filters.setParamsByID: %s", modelId, err.Error())
+					}
+					newParamMap, ok := newValAny.(map[string]any)
+					if !ok {
+						return Config{}, fmt.Errorf("model %s filters.setParamsByID: unexpected type after macro substitution", modelId)
+					}
+					newSetParamsByID[newKey] = newParamMap
+				}
+				modelConfig.Filters.SetParamsByID = newSetParamsByID
+			}
+
 			// Substitute in metadata (type-preserving)
 			if len(modelConfig.Metadata) > 0 {
 				result, err := substituteMacroInValue(modelConfig.Metadata, entry.Name, entry.Value)
@@ -359,6 +377,34 @@ func LoadConfigFromReader(r io.Reader) (Config, error) {
 			}
 		}

+		// Validate SetParamsByID keys and values
+		for key, paramMap := range modelConfig.Filters.SetParamsByID {
+			if matches := macroPatternRegex.FindAllStringSubmatch(key, -1); len(matches) > 0 {
+				return Config{}, fmt.Errorf("unknown macro '${%s}' found in model %s filters.setParamsByID key", matches[0][1], modelId)
+			}
+			if err := validateNestedForUnknownMacros(any(paramMap), fmt.Sprintf("model %s filters.setParamsByID[%s]", modelId, key)); err != nil {
+				return Config{}, err
+			}
+		}
+
+		// Auto-register setParamsByID keys as aliases (skip the model's own ID)
+		for key := range modelConfig.Filters.SetParamsByID {
+			if key == modelId {
+				continue
+			}
+			if _, exists := config.Models[key]; exists {
+				return Config{}, fmt.Errorf("model %s filters.setParamsByID: key '%s' conflicts with an existing model ID", modelId, key)
+			}
+			if existingModel, exists := config.aliases[key]; exists {
+				if existingModel != modelId {
+					return Config{}, fmt.Errorf("duplicate alias '%s' in model %s filters.setParamsByID, already used by model %s", key, modelId, existingModel)
+				}
+				continue // already registered as explicit alias for this model
+			}
+			config.aliases[key] = modelId
+			modelConfig.Aliases = append(modelConfig.Aliases, key)
+		}
+
 		if _, err := url.Parse(modelConfig.Proxy); err != nil {
 			return Config{}, fmt.Errorf("model %s: invalid proxy URL: %w", modelId, err)
 		}
@@ -20,6 +20,12 @@ type Filters struct {
 	// SetParams is a dictionary of parameters to set/override in requests
 	// Protected params (like "model") cannot be set
 	SetParams map[string]any `yaml:"setParams"`
+
+	// SetParamsByID maps requested model IDs to parameters to set/override in requests.
+	// Useful with aliases: a single loaded model can behave differently depending on
+	// which alias the client used. Applied after SetParams, so it can override those values.
+	// Protected params (like "model") cannot be set.
+	SetParamsByID map[string]map[string]any `yaml:"setParamsByID"`
 }

 // SanitizedStripParams returns a sorted list of parameters to strip,
@@ -51,6 +57,33 @@ func (f Filters) SanitizedStripParams() []string {
 	return cleaned
 }

+// SanitizedSetParamsByID returns the params to set for the given requestedModelID,
+// with protected params removed and keys sorted for consistent iteration order.
+// Returns nil if the ID has no entry or all its params are protected.
+func (f Filters) SanitizedSetParamsByID(requestedModelID string) (map[string]any, []string) {
+	if len(f.SetParamsByID) == 0 {
+		return nil, nil
+	}
+	params, found := f.SetParamsByID[requestedModelID]
+	if !found || len(params) == 0 {
+		return nil, nil
+	}
+	result := make(map[string]any, len(params))
+	keys := make([]string, 0, len(params))
+	for key, value := range params {
+		if slices.Contains(ProtectedParams, key) {
+			continue
+		}
+		result[key] = value
+		keys = append(keys, key)
+	}
+	sort.Strings(keys)
+	if len(result) == 0 {
+		return nil, nil
+	}
+	return result, keys
+}
+
 // SanitizedSetParams returns a copy of SetParams with protected params removed
 // and keys sorted for consistent iteration order
 func (f Filters) SanitizedSetParams() (map[string]any, []string) {
@@ -162,6 +162,123 @@ func TestFilters_SanitizedSetParams(t *testing.T) {
 	}
 }

+func TestFilters_SanitizedSetParamsByID(t *testing.T) {
+	tests := []struct {
+		name             string
+		setParamsByID    map[string]map[string]any
+		requestedModelID string
+		wantParams       map[string]any
+		wantKeys         []string
+	}{
+		{
+			name:             "empty SetParamsByID returns nil",
+			setParamsByID:    nil,
+			requestedModelID: "model1",
+			wantParams:       nil,
+			wantKeys:         nil,
+		},
+		{
+			name:             "empty map returns nil",
+			setParamsByID:    map[string]map[string]any{},
+			requestedModelID: "model1",
+			wantParams:       nil,
+			wantKeys:         nil,
+		},
+		{
+			name: "non-matching model ID returns nil",
+			setParamsByID: map[string]map[string]any{
+				"model2": {"temperature": 0.9},
+			},
+			requestedModelID: "model1",
+			wantParams:       nil,
+			wantKeys:         nil,
+		},
+		{
+			name: "matching model ID returns correct params",
+			setParamsByID: map[string]map[string]any{
+				"model1": {"temperature": 0.7, "top_p": 0.9},
+				"model2": {"temperature": 0.5},
+			},
+			requestedModelID: "model1",
+			wantParams: map[string]any{
+				"temperature": 0.7,
+				"top_p":       0.9,
+			},
+			wantKeys: []string{"temperature", "top_p"},
+		},
+		{
+			name: "protected param model is filtered out",
+			setParamsByID: map[string]map[string]any{
+				"model1": {
+					"model":       "should-be-filtered",
+					"temperature": 0.7,
+				},
+			},
+			requestedModelID: "model1",
+			wantParams: map[string]any{
+				"temperature": 0.7,
+			},
+			wantKeys: []string{"temperature"},
+		},
+		{
+			name: "only protected param returns nil",
+			setParamsByID: map[string]map[string]any{
+				"model1": {
+					"model": "should-be-filtered",
+				},
+			},
+			requestedModelID: "model1",
+			wantParams:       nil,
+			wantKeys:         nil,
+		},
+		{
+			name: "keys are sorted",
+			setParamsByID: map[string]map[string]any{
+				"model1": {
+					"z_param": "z",
+					"a_param": "a",
+					"m_param": "m",
+				},
+			},
+			requestedModelID: "model1",
+			wantParams: map[string]any{
+				"z_param": "z",
+				"a_param": "a",
+				"m_param": "m",
+			},
+			wantKeys: []string{"a_param", "m_param", "z_param"},
+		},
+		{
+			name: "alias style key lookup",
+			setParamsByID: map[string]map[string]any{
+				"model1:high": {"reasoning_effort": "high"},
+				"model1:low":  {"reasoning_effort": "low"},
+			},
+			requestedModelID: "model1:high",
+			wantParams: map[string]any{
+				"reasoning_effort": "high",
+			},
+			wantKeys: []string{"reasoning_effort"},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			f := Filters{SetParamsByID: tt.setParamsByID}
+			gotParams, gotKeys := f.SanitizedSetParamsByID(tt.requestedModelID)
+
+			if tt.wantParams == nil {
+				assert.Nil(t, gotParams)
+				assert.Nil(t, gotKeys)
+				return
+			}
+
+			assert.Equal(t, tt.wantKeys, gotKeys)
+			assert.Equal(t, tt.wantParams, gotParams)
+		})
+	}
+}
+
 func TestProtectedParams(t *testing.T) {
 	// Verify that "model" is protected
 	assert.Contains(t, ProtectedParams, "model")
@@ -73,6 +73,72 @@ models:
 	}
 }

+func TestConfig_SetParamsByIDAutoAlias(t *testing.T) {
+	content := `
+models:
+  model1:
+    cmd: path/to/cmd --port ${PORT}
+    filters:
+      setParamsByID:
+        "${MODEL_ID}:high":
+          reasoning_effort: high
+        "${MODEL_ID}:low":
+          reasoning_effort: low
+`
+	cfg, err := LoadConfigFromReader(strings.NewReader(content))
+	assert.NoError(t, err)
+
+	// Keys (other than the model's own ID) should be registered as aliases
+	realName, found := cfg.RealModelName("model1:high")
+	assert.True(t, found, "model1:high should be an auto-registered alias")
+	assert.Equal(t, "model1", realName)
+
+	realName, found = cfg.RealModelName("model1:low")
+	assert.True(t, found, "model1:low should be an auto-registered alias")
+	assert.Equal(t, "model1", realName)
+
+	// Auto-aliases should also appear in modelConfig.Aliases
+	aliases := cfg.Models["model1"].Aliases
+	assert.Contains(t, aliases, "model1:high")
+	assert.Contains(t, aliases, "model1:low")
+}
+
+func TestConfig_SetParamsByIDAutoAliasConflictWithModelID(t *testing.T) {
+	content := `
+models:
+  model1:
+    cmd: path/to/cmd --port ${PORT}
+    filters:
+      setParamsByID:
+        model2:
+          reasoning_effort: high
+  model2:
+    cmd: path/to/cmd --port ${PORT}
+`
+	_, err := LoadConfigFromReader(strings.NewReader(content))
+	assert.ErrorContains(t, err, "conflicts with an existing model ID")
+}
+
+func TestConfig_SetParamsByIDAutoAliasConflictWithOtherModel(t *testing.T) {
+	content := `
+models:
+  model1:
+    cmd: path/to/cmd --port ${PORT}
+    filters:
+      setParamsByID:
+        "shared-alias":
+          reasoning_effort: high
+  model2:
+    cmd: path/to/cmd --port ${PORT}
+    filters:
+      setParamsByID:
+        "shared-alias":
+          reasoning_effort: low
+`
+	_, err := LoadConfigFromReader(strings.NewReader(content))
+	assert.ErrorContains(t, err, "duplicate alias")
+}
+
 func TestConfig_ModelFiltersWithSetParams(t *testing.T) {
 	content := `
 models: