feat: replace WASM embeddings with persistent chroma-mcp MCP connection (#1176)

Browse Source

* feat: replace WASM embeddings with persistent chroma-mcp MCP connection

Replace ChromaServerManager (npx chroma run + chromadb npm + ONNX/WASM)
with ChromaMcpManager, a singleton stdio MCP client that communicates with
chroma-mcp via uvx. This eliminates native binary issues, segfaults, and
WASM embedding failures that plagued cross-platform installs.

Key changes:
- Add ChromaMcpManager: singleton MCP client with lazy connect, auto-reconnect,
  connection lock, and Zscaler SSL cert support
- Rewrite ChromaSync to use MCP tool calls instead of chromadb npm client
- Handle chroma-mcp's non-JSON responses (plain text success/error messages)
- Treat "collection already exists" as idempotent success
- Wire ChromaMcpManager into GracefulShutdown for clean subprocess teardown
- Delete ChromaServerManager (no longer needed)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* fix: address PR review — connection guard leak, timer leak, async reset

- Clear connecting guard in finally block to prevent permanent reconnection block
- Clear timeout after successful connection to prevent timer leak
- Make reset() async to await stop() before nullifying instance
- Delete obsolete chroma-server-manager test (imports deleted class)
- Update graceful-shutdown test to use chromaMcpManager property name

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* fix: prevent chroma-mcp spawn storm — zombie cleanup, stale onclose guard, reconnect backoff

Three bugs caused chroma-mcp processes to accumulate (92+ observed):

1. Zombie on timeout: failed connections left subprocess alive because
   only the timer was cleared, not the transport. Now catch block
   explicitly closes transport+client before rethrowing.

2. Stale onclose race: old transport's onclose handler captured `this`
   and overwrote the current connection reference after reconnect,
   orphaning the new subprocess. Now guarded with reference check.

3. No backoff: every failure triggered immediate reconnect. With
   backfill doing hundreds of MCP calls, this created rapid-fire
   spawning. Added 10s backoff on both connection failure and
   unexpected process death.

Also includes ChromaSync fixes from PR review:
- queryChroma deduplication now preserves index-aligned arrays
- SQL injection guard on backfill ID exclusion lists

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

...

This commit is contained in:

Alex Newman

2026-02-18 18:32:38 -05:00

committed by GitHub

parent 7e57b6e02d

commit 40daf8f3fa

13 changed files with 833 additions and 1189 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download Patch File Download Diff File Expand all files Collapse all files

plugin/scripts/context-generator.cjs

+5 -5

File diff suppressed because one or more lines are too long

plugin/scripts/worker-service.cjs

+258 -305

File diff suppressed because one or more lines are too long