dify/api

Dify Backend API

Setup and Run

Important

In the v1.3.0 release, poetry has been replaced with uv as the package manager for Dify API backend service.

uv and pnpm are required to run the setup and development commands below.

Using scripts (recommended)

The scripts resolve paths relative to their location, so you can run them from anywhere.

1. Run setup (copies env files and installs dependencies).

   ./dev/setup
   

2. Review api/.env, web/.env.local, and docker/middleware.env values (see the SECRET_KEY note below).

3. Start middleware (PostgreSQL/Redis/Weaviate).

   ./dev/start-docker-compose
   

4. Start backend (runs migrations first).

   ./dev/start-api
   

5. Start Dify web service.

   ./dev/start-web
   

6. Set up your application by visiting http://localhost:3000.

7. Optional: start the worker service (async tasks, runs from api).

   ./dev/start-worker
   

8. Optional: start Celery Beat (scheduled tasks).

   ./dev/start-beat
   

Manual commands

Show manual setup and run steps

These commands assume you start from the repository root.

1. Start the docker-compose stack.

   The backend requires middleware, including PostgreSQL, Redis, and Weaviate, which can be started together using docker-compose.

   cp docker/middleware.env.example docker/middleware.env
   # Use mysql or another vector database profile if you are not using postgres/weaviate.
   docker compose -f docker/docker-compose.middleware.yaml --profile postgresql --profile weaviate -p dify up -d
   

2. Copy env files.

   cp api/.env.example api/.env
   cp web/.env.example web/.env.local
   

3. Install UV if needed.

   pip install uv
   # Or on macOS
   brew install uv
   

4. Install API dependencies.

   cd api
   uv sync --group dev
   

5. Install web dependencies.

   cd web
   pnpm install
   cd ..
   

6. Start backend (runs migrations first, in a new terminal).

   cd api
   uv run flask db upgrade
   uv run flask run --host 0.0.0.0 --port=5001 --debug
   

7. Start Dify web service (in a new terminal).

   cd web
   pnpm dev:inspect
   

8. Set up your application by visiting http://localhost:3000.

9. Optional: start the worker service (async tasks, in a new terminal).

   cd api
   uv run celery -A app.celery worker -P threads -c 2 --loglevel INFO -Q dataset,priority_dataset,priority_pipeline,pipeline,mail,ops_trace,app_deletion,plugin,workflow_storage,conversation,workflow,schedule_poller,schedule_executor,triggered_workflow_dispatcher,trigger_refresh_executor,retention
   

10. Optional: start Celery Beat (scheduled tasks, in a new terminal).

    cd api
    uv run celery -A app.celery beat
    

Environment notes

Important

When the frontend and backend run on different subdomains, set COOKIE_DOMAIN to the site’s top-level domain (e.g., example.com). The frontend and backend must be under the same top-level domain in order to share authentication cookies.

• Generate a SECRET_KEY in the .env file.

  bash for Linux

  sed -i "/^SECRET_KEY=/c\\SECRET_KEY=$(openssl rand -base64 42)" .env
  

  bash for Mac

  secret_key=$(openssl rand -base64 42)
  sed -i '' "/^SECRET_KEY=/c\\
  SECRET_KEY=${secret_key}" .env
  

Testing

1. Install dependencies for both the backend and the test environment

   cd api
   uv sync --group dev
   

2. Run the tests locally with mocked system environment variables in tool.pytest_env section in pyproject.toml, more can check Claude.md

   cd api
   uv run pytest                           # Run all tests
   uv run pytest tests/unit_tests/         # Unit tests only
   uv run pytest tests/integration_tests/  # Integration tests
   
   # Code quality
   ./dev/reformat               # Run all formatters and linters
   uv run ruff check --fix ./   # Fix linting issues
   uv run ruff format ./        # Format code
   uv run basedpyright .        # Type checking