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Swagger UI

What is Swagger UI?​

Swagger UI renders an OpenAPI (formerly Swagger) specification as interactive, browsable API documentation, complete with a "try it out" panel for firing real requests at your API. Laradock builds it from the official swaggerapi/swagger-ui image.

Start Swagger UI​

docker compose up -d swagger-ui

Stop Swagger UI​

docker compose stop swagger-ui

Configuration​

All settings live in swagger-ui/defaults.env and can be overridden by adding the same line to your own .env:

VariableDefaultWhat it does
SWAGGER_API_URLhttp://generator.swagger.io/api/swagger.jsonThe URL Swagger UI fetches its OpenAPI spec from, passed into the container as the API_URL environment variable.
SWAGGER_UI_PORT5555Host-side port Swagger UI is published on (host:8080, the UI listens on 8080 inside the container).

Point it at your own API spec​

SWAGGER_API_URL=http://your-app.test/api/openapi.json
docker compose up -d swagger-ui

Open http://localhost:5555 (or your custom SWAGGER_UI_PORT). SWAGGER_API_URL must be reachable from inside the swagger-ui container, so if your spec is served by another Laradock container, use its container name (for example http://nginx/api/openapi.json) rather than localhost.

Common issues​

  • Still showing the default demo spec. SWAGGER_API_URL only takes effect on container start. Set it in .env and re-run docker compose up -d swagger-ui to apply it.
  • "Failed to fetch" when loading your spec. If your API lives in another Laradock container, localhost from inside swagger-ui refers to the swagger-ui container itself, not your host or your API container. Use the API's container name instead (Laradock containers share the backend network).
  • CORS errors in the browser console. Swagger UI fetches the spec client-side from your browser, not just server-side, so your API must also send CORS headers allowing the origin http://localhost:5555 (or your custom port).
  • Port already in use on your host. Another service (or another Laradock project) is already bound to 5555. Change SWAGGER_UI_PORT in .env and restart.

Writing the spec by hand? See Swagger Editor. New to Laradock? Start at Getting Started.