The undo substrate. The agent is going to act freely — "empty the garlic bed and
plant cucumbers" runs without a confirmation prompt — and that is only a
defensible default if the result is easy to roll back. So undo lands before the
agent write path, not after it.
The unit of undo is the OPERATION, not the row. A change set groups the
row-level revisions it produced; revert replays their inverses. Emptying a bed
and replanting it touches one object and many plantings, and undoing half of
that is worse than useless.
Two properties shape the rest:
Revert is itself a change set (reverts_id names its target), so history is
append-only and an undo can be undone. git revert, not git reset.
Revert is version-guarded per entity. Every snapshot carries the row's version;
if something edited that row after the change set being reverted, restoring the
old snapshot would silently discard the newer edit, so it is reported as a
conflict and left alone while the rest of the change set still reverts.
The auto-scope is what keeps this invasive but shallow. Service mutations call
record(), which joins the change set on the context if one is open and otherwise
opens a single-op one on the spot. REST handlers needed no edits at all and
every UI mutation lands in history for free; only the agent wraps a whole turn.
Multi-row operations (FillRegion, ClearObject) pass all their changes in one
record call, so a 12-plop fill is one change set with 12 revisions and one undo.
Revisions are buffered and written with their change set in a single
transaction, so an operation that fails partway leaves no half-recorded history.
Recording is best-effort after the fact: the row is already written, so failing
the caller there would report a failure that didn't happen and invite a
duplicate retry. A gap is logged loudly instead.
Two sharp edges handled explicitly rather than by luck:
Deleting an object cascades its plantings away at the FK level, where the
service never sees them. deleteObjectRecording snapshots them first, or the
delete would be listed in history and not actually be undoable.
Restoring deleted rows reuses their ids, and a restored plop needs its object
back first. planRevert runs three explicit passes — restore parents then
children, then updates, then delete created children before their parents —
instead of trusting reverse-seq ordering to happen to be right.
Garden deletion stays out of scope, as designed: the cascade is invisible to the
service and ON DELETE CASCADE would take the history with it. The history UI
will say so rather than pretend otherwise.
Closes#48
Co-Authored-By: Claude Opus 4.8 (1M context) <[email protected]>
Claude-Session: https://claude.ai/code/session_01H3zbym8Doka2d7D48maSgZ
Closes#44. Two independent grids (garden + per-bed), each with a size and a snap toggle; snapping defaults off. See PR #45 for details.
Co-authored-by: Steve Dudenhoeffer <[email protected]>
Per-garden public read-only link: unauthenticated GET /api/v1/public/gardens/:token (no requireAuth, no OIDC), owner-only enable/rotate/disable, and a /g/$token page rendering GardenCanvas read-only. Review fixes: redact plant owner ids, Cache-Control: no-store, 400 on malformed body, shared resetTransient store action.
Closes#41.
Co-authored-by: Steve Dudenhoeffer <[email protected]>
Fixes from the PR #23 adversarial review (graded 35 real / 1 false positive):
Security / correctness
- Race-free registration: is_admin and the registration gate are now
computed atomically inside a single INSERT...SELECT, so concurrent
first registrations can't both become admin or bypass closed
registration (fixed the whole TOCTOU cluster).
- Sliding session now reaches the browser: ResolveSession returns the
current expiry and requireAuth re-sets the cookie, so active users
aren't logged out 30 days after login regardless of activity.
- Login CSRF: csrfGuard rejects state-changing requests whose Origin
doesn't match PANSY_BASE_URL (no-op when unset, so the dev proxy is
unaffected). SameSite=Lax alone didn't cover this.
- argon2id tuned to RFC 9106's second recommended profile (t=3).
- Timing equalizer can't fail open: the dummy hash is derived
deterministically (fixed salt, no RNG) so it's always present.
- Password length (<=1024) enforced in the service for both register
and login, not just HTTP binding tags; login rejects over-long input
before spending argon2 work.
Error handling / robustness
- Login logs a malformed stored hash instead of silently treating it as
a wrong password.
- Best-effort session writes (Touch/Delete during renewal, expiry, and
corrupt-expiry cleanup) now log on failure.
- index sessions.expires_at via new migration 0002 (0001 is immutable).
Maintainability
- Extract startSessionAndRespond and abortUnauthenticated; make
writeServiceError a free function; consistent error handling in
decodeHash; doc/comment fixes.
Tests: over-long password, CSRF guard (cross-origin/same-origin/dev
no-op), and cookie refresh on authenticated requests; migration-version
assertions bumped to 2.
Co-Authored-By: Claude Opus 4.8 (1M context) <[email protected]>
Claude-Session: https://claude.ai/code/session_01JdQpdYYsTgtkJBxbcpAszi
Implements the Pansy v1 scaffold (epic #20, phase 0).
#1 Backend: Go module (pure-Go, builds with CGO_ENABLED=0), env config,
gin server with slog + recovery + /api/v1/healthz, modernc SQLite store
with WAL/busy_timeout/foreign_keys pragmas, embedded numbered-migration
runner, full initial schema (users, sessions, gardens, garden_shares,
garden_objects, plants, plantings), domain structs + sentinel errors,
graceful shutdown.
#2 Frontend: Vite + React 19 + TS (strict) + Tailwind 4 + TanStack
Router/Query, typed /api/v1 fetch wrapper (ApiError carries status +
body so later issues can read 409 conflict rows), dev proxy /api -> :8080,
responsive app shell with stub pages for all five routes.
#3 Single binary: //go:embed of the web build with a committed placeholder,
SPA fallback (deep links, immutable asset caching, JSON 404 for unmatched
/api and missing assets), Makefile (web/build/dev/test), README quickstart
+ env var table.
Verified: go build/vet/test clean (CGO off); binary migrates idempotently and
serves healthz; web tsc + build clean; integrated binary serves the SPA, deep
links, and correct cache headers; app mounts and navigates all five routes at
desktop and 375px widths.
Co-Authored-By: Claude Opus 4.8 (1M context) <[email protected]>
Claude-Session: https://claude.ai/code/session_01JdQpdYYsTgtkJBxbcpAszi