GitLab AI Code Reviewer

Webhook-driven pipeline system for AI-powered code review on GitLab Merge Requests and Issues.

Current State

Pipeline architecture is in place. The system receives webhooks, detects commands (/oc_review, /oc_ask, /oc_test), and executes multi-stage pipelines. However, OpenCode agent integration is not yet implemented - the AgentExecutorStage currently returns placeholder results.

Architecture

oc_hooks/
├── app.py                      # FastAPI webhook handler (async → sync bridge)
├── src/
│   ├── app_old.py              # Original app (for post_gitlab_note helper)
│   └── pipelines/
│       ├── base.py             # Pipeline, Stage, Context, Result classes
│       ├── registry.py         # Command detection and pipeline factory
│       ├── stages/
│       │   ├── hook_resolver.py    # Detect commands, post "started" note
│       │   ├── snapshot_resolver.py # Resolve SHA/branch from MR
│       │   ├── context_builder.py   # Clone repo to temp directory
│       │   ├── agent_executor.py    # TODO: Run OpenCode agent
│       │   └── note_updater.py      # Post results or errors
│       └── commands/
│           ├── base.py         # Command base class
│           ├── oc_review.py    # /oc_review pipeline
│           ├── oc_ask.py       # /oc_ask pipeline
│           └── oc_test.py      # /oc_test pipeline
└── tests/                      # Unit tests (13 passing)

Commands

• /oc_review - Review code in the merge request
• /oc_ask - Answer questions about the code
• /oc_test - Run tests or analyze test coverage

Running

uv run python app.py

Or with hot reload:

uv run uvicorn app:app --reload --host 0.0.0.0 --port 8585

Known Issues

Recursive Webhook Loop (Hack Fix)

Problem: When the bot posts a note with results, GitLab sends another webhook event, triggering the pipeline again → infinite loop.

Current Hack Fix: The HookResolverStage filters out notes starting with "🤖 OpenCode".

Real Fix (TODO): When using a dedicated bot account, filter by user_id instead of message content. This requires:

1. A GitLab bot account with its own PAT
2. Checking payload.get("user_id") against the bot's user ID
3. Removing the "🤖 OpenCode" string check

OpenCode Agent Integration

The AgentExecutorStage (src/pipelines/stages/agent_executor.py) currently returns placeholder results:

result = AgentResult(
    content=f"Agent result for {self.agent_type}: {prompt[:100]}...",
    format="markdown",
)

This needs to be replaced with actual OpenCode agent invocation.

Setup

1. Configure .env:

   • GITLAB_URL - GitLab instance URL
   • GITLAB_PAT - Personal Access Token
   • HOST/PORT - Server binding

2. Add webhook in GitLab project:

   • URL: http://your-server:8585/webhook
   • Trigger: Comments events

Testing

uv run pytest tests/ -v