feat: add @payloadcms-vectorize/mongodb adapter

.changeset/add-mongodb-adapter.md

@@ -0,0 +1,8 @@
+---
+"payloadcms-vectorize": minor
+"@payloadcms-vectorize/pg": minor
+"@payloadcms-vectorize/cf": minor
+"@payloadcms-vectorize/mongodb": minor
+---
+
+Add `@payloadcms-vectorize/mongodb` adapter (Atlas + self-hosted Community 8.2+) backed by `$vectorSearch`, with pre/post filter splitting and full WHERE-clause parity across operators (equals, not_equals, in, notIn, like, contains, gt/gte/lt/lte, exists, and/or). Search indexes are auto-ensured on first use.

.changeset/config.json

@@ -6,7 +6,7 @@
   ],
   "commit": false,
   "fixed": [
-    ["payloadcms-vectorize", "@payloadcms-vectorize/pg", "@payloadcms-vectorize/cf"]
+    ["payloadcms-vectorize", "@payloadcms-vectorize/pg", "@payloadcms-vectorize/cf", "@payloadcms-vectorize/mongodb"]
   ],
   "access": "public",
   "baseBranch": "main",

.github/workflows/ci.yml

@@ -157,6 +157,42 @@ jobs:
           PAYLOAD_SECRET: test-secret-key
           TEST_ENV: 1
 
+  test_adapters_mongodb:
+    runs-on: ubuntu-latest
+
+    services:
+      mongodb:
+        image: mongodb/mongodb-atlas-local:latest
+        ports:
+          - 27018:27017
+        options: >-
+          --health-cmd "mongosh --quiet --eval 'db.runCommand({ping:1})'"
+          --health-interval 5s
+          --health-timeout 10s
+          --health-retries 30
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Install pnpm
+        uses: pnpm/action-setup@v4
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '20'
+          cache: 'pnpm'
+
+      - name: Install dependencies
+        run: pnpm install
+
+      - name: Run mongodb adapter tests
+        run: pnpm test:adapters:mongodb
+        env:
+          PAYLOAD_SECRET: test-secret-key
+          MONGODB_URI: mongodb://localhost:27018/?directConnection=true
+          TEST_ENV: 1
+
   test_e2e:
     runs-on: ubuntu-latest
 
@@ -231,10 +267,11 @@ jobs:
           test -f dist/index.d.ts
           test -f adapters/pg/dist/index.d.ts
           test -f adapters/cf/dist/index.d.ts
+          test -f adapters/mongodb/dist/index.d.ts
 
   test:
     runs-on: ubuntu-latest
-    needs: [typecheck, build, test_int, test_adapters_pg, test_adapters_cf, test_e2e]
+    needs: [typecheck, build, test_int, test_adapters_pg, test_adapters_cf, test_adapters_mongodb, test_e2e]
     if: always()
     steps:
       - name: Check required jobs
@@ -244,6 +281,7 @@ jobs:
              [ "${{ needs.test_int.result }}" != "success" ] || \
              [ "${{ needs.test_adapters_pg.result }}" != "success" ] || \
              [ "${{ needs.test_adapters_cf.result }}" != "success" ] || \
+             [ "${{ needs.test_adapters_mongodb.result }}" != "success" ] || \
              [ "${{ needs.test_e2e.result }}" != "success" ]; then
             echo "One or more required jobs failed"
             exit 1

.gitignore

@@ -22,6 +22,7 @@ node_modules/
 /dist
 /adapters/pg/dist
 /adapters/cf/dist
+/adapters/mongodb/dist
 
 # misc
 .DS_Store
@@ -55,4 +56,7 @@ yarn-error.log*
 */secret
 
 # Cursor
-.cursor/
+.cursor/
+
+# Worktrees
+.worktrees/

README.md

@@ -52,10 +52,11 @@ A Payload CMS plugin that adds vector search capabilities to your collections. P
 
 This plugin requires a database adapter for vector storage. Available adapters:
 
-| Adapter              | Package                    | Database                    | Documentation                     |
-| -------------------- | -------------------------- | --------------------------- | --------------------------------- |
-| PostgreSQL           | `@payloadcms-vectorize/pg` | PostgreSQL with pgvector    | [README](./adapters/pg/README.md) |
-| Cloudflare Vectorize | `@payloadcms-vectorize/cf` | Cloudflare Vectorize index  | [README](./adapters/cf/README.md) |
+| Adapter              | Package                         | Database                                | Documentation                          |
+| -------------------- | ------------------------------- | --------------------------------------- | -------------------------------------- |
+| PostgreSQL           | `@payloadcms-vectorize/pg`      | PostgreSQL with pgvector                | [README](./adapters/pg/README.md)      |
+| Cloudflare Vectorize | `@payloadcms-vectorize/cf`      | Cloudflare Vectorize index              | [README](./adapters/cf/README.md)      |
+| MongoDB              | `@payloadcms-vectorize/mongodb` | MongoDB Atlas + self-hosted 8.2+        | [README](./adapters/mongodb/README.md) |
 
 See [adapters/README.md](./adapters/README.md) for information on creating custom adapters.
 
@@ -72,8 +73,9 @@ See [adapters/README.md](./adapters/README.md) for information on creating custo
 pnpm add payloadcms-vectorize
 
 # Install a database adapter (one of the following)
-pnpm add @payloadcms-vectorize/pg   # PostgreSQL + pgvector
-pnpm add @payloadcms-vectorize/cf   # Cloudflare Vectorize
+pnpm add @payloadcms-vectorize/pg        # PostgreSQL + pgvector
+pnpm add @payloadcms-vectorize/cf        # Cloudflare Vectorize
+pnpm add @payloadcms-vectorize/mongodb   # MongoDB Atlas + self-hosted 8.2+
 ```
 
 ## Quick Start
@@ -84,6 +86,7 @@ First, configure your database adapter. See the adapter-specific documentation:
 
 - **PostgreSQL**: [@payloadcms-vectorize/pg README](./adapters/pg/README.md) — pgvector setup, schema initialization, and migrations.
 - **Cloudflare Vectorize**: [@payloadcms-vectorize/cf README](./adapters/cf/README.md) — index creation, bindings, and known limitations.
+- **MongoDB**: [@payloadcms-vectorize/mongodb README](./adapters/mongodb/README.md) — Atlas / self-hosted 8.2+, `filterableFields`, and the `$vectorSearch` index lifecycle.
 
 ### 2. Configure the Plugin
 
@@ -222,6 +225,7 @@ Migration steps depend on your database adapter:
 
 - **PostgreSQL**: [@payloadcms-vectorize/pg README → Migrations](./adapters/pg/README.md#migrations)
 - **Cloudflare Vectorize**: index creation is a one-time setup step — see [@payloadcms-vectorize/cf README](./adapters/cf/README.md#1-create-vectorize-index).
+- **MongoDB**: no manual migration — the `$vectorSearch` index is auto-ensured on first write. See [@payloadcms-vectorize/mongodb README → Index lifecycle](./adapters/mongodb/README.md#index-lifecycle).
 
 ### 4. Search Your Content
 
@@ -298,6 +302,7 @@ Each adapter has its own configuration shape — this is where index parameters,
 
 - **PostgreSQL** (`dims`, `ivfflatLists`, schema initialization): [@payloadcms-vectorize/pg → Static Configuration](./adapters/pg/README.md#static-configuration)
 - **Cloudflare Vectorize** (`dims`, Vectorize binding): [@payloadcms-vectorize/cf → Configuration](./adapters/cf/README.md#configuration)
+- **MongoDB** (`uri`, `dbName`, per-pool `dimensions` / `similarity` / `filterableFields` / `numCandidates` / `forceExact`): [@payloadcms-vectorize/mongodb → API Reference](./adapters/mongodb/README.md#api-reference)
 
 The embeddings collection name in Payload will be the same as the knowledge pool name.
 
@@ -374,7 +379,7 @@ You can filter on:
 
 References to fields that don't exist on the embeddings table are silently dropped (the rest of the clause still applies).
 
-> **Adapter parity.** All operators are implemented in `@payloadcms-vectorize/pg`. The Cloudflare Vectorize adapter has narrower native filtering — see [@payloadcms-vectorize/cf → Known Limitations](./adapters/cf/README.md#metadata-filtering) for what is and isn't supported there.
+> **Adapter parity.** All operators are implemented in `@payloadcms-vectorize/pg`. The Cloudflare Vectorize adapter has narrower native filtering — see [@payloadcms-vectorize/cf → Known Limitations](./adapters/cf/README.md#metadata-filtering) for what is and isn't supported there. The MongoDB adapter splits the clause into a native `$vectorSearch` pre-filter and a JS post-filter — `like`/`contains`/`all` and any mixed-pre/post `or` are post-filtered, so they may return fewer than `limit` rows. See [@payloadcms-vectorize/mongodb → WHERE clause behavior](./adapters/mongodb/README.md#where-clause-behavior).
 
 ## Chunkers
 
@@ -1006,15 +1011,15 @@ Common scripts:
 **Already shipped:**
 
 - **Multiple Knowledge Pools** — independent configurations and embedding functions per pool.
-- **Database Adapter Architecture** — pluggable backends (PostgreSQL, Cloudflare Vectorize today).
+- **Database Adapter Architecture** — pluggable backends (PostgreSQL, Cloudflare Vectorize, MongoDB today).
 - **More expressive queries** — configurable limits, per-collection scoping, and full Payload-style metadata filtering (see [Metadata Filtering](#metadata-filtering-where)).
 - **Bulk Embed All** — admin button, provider callbacks, and run/batch tracking.
 - **Serverless-friendly job model** — bulk runs are split into small, requeueable units (`prepare-bulk-embedding` and `poll-or-complete-single-batch`) so individual jobs stay well under typical serverless time limits. The `batchLimit` option (see [CollectionVectorizeOption](#collectionvectorizeoption)) lets you cap docs-per-job to fit your platform. Tested locally and on Node-style hosts; deeper Vercel-specific integration testing is on the help-wanted list.
 - **Cloudflare Vectorize adapter** — `@payloadcms-vectorize/cf`.
+- **MongoDB adapter** — `@payloadcms-vectorize/mongodb` (Atlas + self-hosted Community 8.2+ via `$vectorSearch`).
 
 **Help wanted** (priority is driven by community demand — open or 👍 an issue to push something up):
 
-- **MongoDB adapter** — `@payloadcms-vectorize/mongodb` for MongoDB Atlas Vector Search.
 - **Additional adapters** — Pinecone, Qdrant, SQLite, etc. See [adapters/README.md](./adapters/README.md) for the `DbAdapter` contract.
 - **Vercel CI matrix** — exercising the serverless job model end-to-end on Vercel preview deployments.
 

adapters/README.md

@@ -37,10 +37,11 @@
 
 ## Available Adapters
 
-| Adapter              | Package                                       | Database                   | Version  | Status      |
-| -------------------- | --------------------------------------------- | -------------------------- | -------- | ----------- |
-| PostgreSQL           | [`@payloadcms-vectorize/pg`](./pg/README.md)  | PostgreSQL with `pgvector` | `0.7.2`  | Stable      |
-| Cloudflare Vectorize | [`@payloadcms-vectorize/cf`](./cf/README.md)  | Cloudflare Vectorize index | `0.7.2`  | Beta        |
+| Adapter              | Package                                                       | Database                          | Version  | Status      |
+| -------------------- | ------------------------------------------------------------- | --------------------------------- | -------- | ----------- |
+| PostgreSQL           | [`@payloadcms-vectorize/pg`](./pg/README.md)                  | PostgreSQL with `pgvector`        | `0.7.2`  | Stable      |
+| Cloudflare Vectorize | [`@payloadcms-vectorize/cf`](./cf/README.md)                  | Cloudflare Vectorize index        | `0.7.2`  | Beta        |
+| MongoDB              | [`@payloadcms-vectorize/mongodb`](./mongodb/README.md)        | MongoDB Atlas + self-hosted 8.2+  | `0.7.2`  | Beta        |
 
 ## Architecture