Builds on merged PR-1 (#2729), independent of PR-2/PR-4.
Implements every endpoint of the v1 plugin contract behind an HTTP
server (cmd/memory-plugin-postgres/) backed by postgres. Operators
run this binary next to workspace-server; it's the default
implementation MEMORY_PLUGIN_URL points at.
What ships:
- cmd/memory-plugin-postgres/main.go: boot, signal-driven shutdown,
boot-time migrations, configurable LISTEN/DATABASE/MIGRATION_DIR
- cmd/memory-plugin-postgres/migrations/001_memory_v2.up.sql:
memory_namespaces (PK on name, kind CHECK, expires_at, metadata)
memory_records (FK to namespaces with CASCADE, kind+source CHECK,
pgvector embedding, FTS tsvector, ivfflat partial
index on embedding, partial index on expires_at)
- internal/memory/pgplugin/store.go: storage layer using lib/pq
- internal/memory/pgplugin/handlers.go: HTTP layer (no router dep —
a switch on URL.Path keeps the binary's dep surface tiny)
- 100% statement coverage on store.go + handlers.go
Schema notes:
- These tables live next to the plugin binary, NOT in workspace-
server/migrations/. When operators swap the plugin, these tables
become orphaned (operator drops manually). Documented in PR-10.
- Search supports semantic (pgvector cosine) → FTS (>=2 char query)
→ ILIKE (1-char query) → recent-listing (no query), with a TTL
filter applied uniformly across all paths.
- DELETE on namespace cascades to memory_records (FK ON DELETE
CASCADE) — a deleted namespace immediately frees its memories.
Coverage corner cases pinned:
- Health: ok, degraded (db ping fails), no-ping fn
- Every CRUD endpoint: happy path, bad name, bad JSON, bad body,
not-found, store errors, exec/scan/marshal errors
- Search: FTS, semantic, short-query (ILIKE), no-query (recent),
kinds filter, store errors, scan errors, mid-iteration row error
- Routing edge cases: unknown path, empty namespace, unknown sub,
method-not-allowed, GET on /v1/health (allowed), POST on /v1/health
(404), GET on /v1/search (404)
- Helper internals: marshalMetadata (nil/happy/unmarshalable),
nullTime (nil/non-nil), vectorString (empty/format),
nullVectorString (empty/non-empty), scanNamespace +
scanMemory metadata-decode errors
No callers in workspace-server yet; integration starts in PR-5
(MCP handlers wire the plugin client through to MCP tools).