Add an ephemeral, process-local blob store so the in-app agent (and the
embedded MCP) can hand a large page document and its images to an external
consumer WITHOUT routing the bytes through the model context or Docmost auth.
- SandboxStore (@Injectable singleton): Map<uuid,{buf,mime,sha256,expiresAt}>
in RAM only. put() picks a per-blob cap by mime (image vs doc), enforces a
total-bytes RAM guard with oldest-first eviction, and stamps a TTL; get()
lazily expires. sha256 computed at put() doubles as the strong ETag. An
unref'd sweep interval clears expired entries and is cleared on destroy.
- GET /api/sb/:uuid anonymous controller: serves raw bytes with Content-Type,
Content-Length and ETag=sha256; 404 on missing/expired/non-UUID (anti-
traversal), 304 on a matching If-None-Match. No tokens, no 401 — the
capability is the unguessable UUID + short TTL + TLS. Auth-exempt the same
way as /api/files/public (no JwtAuthGuard) plus an /api/sb entry in main.ts's
workspace-resolution preHandler so a remote consumer with no workspace host
is not rejected.
- stash_page tool in both layers (MCP resource_link + in-app {uri,size,sha256,
images}). client.stashPage serializes the get_page_json shape, mirrors every
INTERNAL file/image src (type-agnostic, covers drawio/excalidraw/video/file)
into the sandbox under Docmost auth and rewrites src to the sandbox URL;
external http(s) srcs are left untouched; dedup by src; a failed image fetch
is counted, never aborts the doc.
- SANDBOX_PUBLIC_URL / SANDBOX_TTL_MS / SANDBOX_MAX_BYTES /
SANDBOX_MAX_IMAGE_BYTES / SANDBOX_MAX_TOTAL_BYTES wired through the
environment service + validation + .env.example.
- SandboxModule (@Global) provides the shared store to the controller,
McpService and AiChatToolsService (same instance for put and get).
Tests: SandboxStore (round-trip, sha256, TTL lazy + sweep, caps, eviction),
SandboxController (200+ETag+CT+CL, 404 missing/expired/non-UUID, 304), and a
mock-HTTP stashPage test (mirror+rewrite internal, keep external, dedup, failed
image counted, returns only a link). Interoperates with the vvzvlad/habr-mcp
consumer's anonymous-GET + sha256-ETag + resource_link contract.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2fe4ca8537