# yaml-language-server: $schema=https://json.schemastore.org/traefik-v3-file-provider.json
http:
  routers:
    imaging-cache:
      rule: PathPrefix(`/imaging-cache`)
      middlewares:
        - imaging-cache # before the prefix is stripped: the cache key is the public URL
        - imaging-prefix
      service: imaging
    # Validation: the backend sends an `ETag` and answers `304` to `If-None-Match`. Here its responses are only
    # fresh for 2 seconds: after that, the cache asks it whether the stored image is still current
    imaging-validate:
      rule: PathPrefix(`/imaging-validate`)
      middlewares:
        - imaging-client # acts on the Cache-Control of clients: e2e/tests/request.hurl asks for stale responses
        - imaging-validate-headers # after the cache: for the cache, this header comes from the backend
        - imaging-prefix
      service: imaging
    # Errors stored too: here a missing source image (`404`) is stored like an image, for `defaultTtl`
    imaging-cache-errors:
      rule: PathPrefix(`/imaging-cache-errors`)
      middlewares:
        - imaging-cache-errors
        - imaging-prefix
      service: imaging
    imaging:
      rule: PathPrefix(`/imaging`)
      middlewares:
        - imaging-prefix
      service: imaging

  middlewares:
    # The backend serves /<signature>/<processing options>/plain/<source URL>
    imaging-prefix:
      stripPrefix:
        prefixes:
          - /imaging-cache-errors # first: /imaging-cache is its prefix
          - /imaging-cache
          - /imaging-validate
          - /imaging # last: the others start with it
    imaging-validate-headers:
      headers:
        customResponseHeaders:
          Cache-Control: "max-age=2"
    imaging-cache:
      plugin:
        traedis:
          redis:
            dsn: "redis://cache:6379/0"
          defaultTtl: 5m # 0 by default: imgproxy sends no Cache-Control with its errors, which statusCodes keeps out here

    imaging-client:
      plugin:
        traedis:
          redis:
            dsn: "redis://cache:6379/0"
          followClientCacheControl: true # off by default: request directives are advisory (RFC 9111 §5.2.1)

    imaging-cache-errors:
      plugin:
        traedis:
          redis:
            dsn: "redis://cache:6379/0"
          defaultTtl: 5m
          statusCodes: [ "200-399", 404 ] # the default, and 404

  services:
    imaging:
      loadBalancer:
        servers:
          - url: "http://imaging:8080"