ContentType

    The Content-Type middleware - or rather its autoDetect option - specifies whether to let the Content-Type header, if it has not been defined by the backend, be automatically set to a value derived from the contents of the response.

    As a proxy, the default behavior should be to leave the header alone, regardless of what the backend did with it. However, the historic default was to always auto-detect and set the header if it was not already defined, and altering this behavior would be a breaking change which would impact many users.

    This middleware exists to enable the correct behavior until at least the default one can be changed in a future version.

    Info

    The scope of the Content-Type middleware is the MIME type detection done by the core of Traefik (the server part). Therefore, it has no effect against any other Content-Type header modifications (e.g.: in another middleware such as compress).

    Docker

    Kubernetes

    1. # Disable auto-detection
    2. apiVersion: traefik.containo.us/v1alpha1
    4.   name: autodetect
    5. spec:
    6.   contentType:
    7.     autoDetect: false

    Consul Catalog

    1. "labels": {
    2.   "traefik.http.middlewares.autodetect.contenttype.autodetect": "false"

    Rancher

    File (YAML)

    1. # Disable auto-detection
    2. http:
    3.   middlewares:
    4.     autodetect:
    5.       contentType:
    6.         autoDetect: false

    File (TOML)

    Configuration Options

    specifies whether to let the Content-Type header, if it has not been set by the backend, be automatically set to a value derived from the contents of the response.