Traefik StripPrefixRegex Documentation - Traefik

The stripPrefixRegex middleware strips the matching path prefix and stores it in an X-Forwarded-Prefix header.

!!! tip

Use a `stripPrefixRegex` middleware if your backend listens on the root path (`/`) but should be exposed on a specific prefix.

Configuration Example

yaml

http:
  middlewares:
    test-stripprefixregex:
      stripPrefixRegex:
        regex:
          - "/foo/[a-z0-9]+/[0-9]+/"

toml

[http.middlewares]
  [http.middlewares.test-stripprefixregex.stripPrefixRegex]
    regex = ["/foo/[a-z0-9]+/[0-9]+/"]

yaml

labels:
  - "traefik.http.middlewares.test-stripprefixregex.stripprefixregex.regex=/foo/[a-z0-9]+/[0-9]+/"

yaml

{
  //..
  "Tags" : [
    "traefik.http.middlewares.test-stripprefixregex.stripprefixregex.regex=/foo/[a-z0-9]+/[0-9]+/"
  ]
}
-

yaml

apiVersion: traefik.io/v1alpha1
kind: Middleware
metadata:
  name: test-stripprefixregex
spec:
  stripPrefixRegex:
    regex:
      - "/foo/[a-z0-9]+/[0-9]+/"

Configuration Options

Field	Description	Default
<a id="opt-regex" href="#opt-regex" title="#opt-regex">`regex`</a>	List of regular expressions to match the path prefix from the request URL.
For instance, `/products` also matches `/products/shoes` and `/products/shirts`.
More information here.		No

regex

If your backend is serving assets (for example, images or JavaScript files), it can use the X-Forwarded-Prefix header to construct relative URLs. Using the previous example, the backend should return /products/shoes/image.png (and not /images.png, which Traefik would likely not be able to associate with the same backend).

!!! tip

Regular expressions and replacements can be tested using online tools such as [Go Playground](https://play.golang.org/p/mWU9p-wk2ru) or the [Regex101](https://regex101.com/r/58sIgx/2).

When defining a regular expression within YAML, any escaped character needs to be escaped twice: `example\.com` needs to be written as `example\\.com`.