traefik/docs/content/reference/routing-configuration/http/middlewares/stripprefixregex.md

title, description

title	description
Traefik StripPrefixRegex Documentation	In Traefik Proxy's HTTP middleware, StripPrefixRegex removes prefixes from paths before forwarding requests, using regex. Read the technical documentation.

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

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

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

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

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

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

Configuration Options

Field	Description	Default	Required
regex	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`.