Middlewares

Tweaking the Request

Overview

Attached to the routers, pieces of middleware are a means of tweaking the requests before they are sent to your service (or before the answer from the services are sent to the clients).

There are several available middleware in Traefik, some can modify the request, the headers, some are in charge of redirections, some add authentication, and so on.

Pieces of middleware can be combined in chains to fit every scenario.

Provider Namespace

Be aware of the concept of Providers Namespace described in the Configuration Discovery section. It also applies to Middlewares.

Configuration Example

Docker

  1. # As a Docker Label
  2. whoami:
  3. # A container that exposes an API to show its IP address
  4. image: traefik/whoami
  5. labels:
  6. # Create a middleware named `foo-add-prefix`
  7. - "traefik.http.middlewares.foo-add-prefix.addprefix.prefix=/foo"
  8. # Apply the middleware named `foo-add-prefix` to the router named `router1`
  9. - "traefik.http.routers.router1.middlewares=foo-add-prefix@docker"

Kubernetes IngressRoute

  1. # As a Kubernetes Traefik IngressRoute
  2. apiVersion: apiextensions.k8s.io/v1beta1
  3. kind: CustomResourceDefinition
  4. metadata:
  5. name: middlewares.traefik.containo.us
  6. spec:
  7. group: traefik.containo.us
  8. version: v1alpha1
  9. names:
  10. kind: Middleware
  11. plural: middlewares
  12. singular: middleware
  13. scope: Namespaced
  14. ---
  15. apiVersion: traefik.containo.us/v1alpha1
  16. kind: Middleware
  17. metadata:
  18. name: stripprefix
  19. spec:
  20. stripPrefix:
  21. prefixes:
  22. - /stripit
  23. ---
  24. apiVersion: traefik.containo.us/v1alpha1
  25. kind: IngressRoute
  26. metadata:
  27. name: ingressroute
  28. spec:
  29. # more fields...
  30. routes:
  31. # more fields...
  32. middlewares:
  33. - name: stripprefix

Consul Catalog

  1. # Create a middleware named `foo-add-prefix`
  2. - "traefik.http.middlewares.foo-add-prefix.addprefix.prefix=/foo"
  3. # Apply the middleware named `foo-add-prefix` to the router named `router1`
  4. - "traefik.http.routers.router1.middlewares=foo-add-prefix@consulcatalog"

Marathon

  1. "labels": {
  2. "traefik.http.middlewares.foo-add-prefix.addprefix.prefix": "/foo",
  3. "traefik.http.routers.router1.middlewares": "foo-add-prefix@marathon"
  4. }

Rancher

  1. # As a Rancher Label
  2. labels:
  3. # Create a middleware named `foo-add-prefix`
  4. - "traefik.http.middlewares.foo-add-prefix.addprefix.prefix=/foo"
  5. # Apply the middleware named `foo-add-prefix` to the router named `router1`
  6. - "traefik.http.routers.router1.middlewares=foo-add-prefix@rancher"

File (TOML)

  1. # As TOML Configuration File
  2. [http.routers]
  3. [http.routers.router1]
  4. service = "myService"
  5. middlewares = ["foo-add-prefix"]
  6. rule = "Host(`example.com`)"
  7. [http.middlewares]
  8. [http.middlewares.foo-add-prefix.addPrefix]
  9. prefix = "/foo"
  10. [http.services]
  11. [http.services.service1]
  12. [http.services.service1.loadBalancer]
  13. [[http.services.service1.loadBalancer.servers]]
  14. url = "http://127.0.0.1:80"

File (YAML)

  1. # As YAML Configuration File
  2. http:
  3. routers:
  4. router1:
  5. service: myService
  6. middlewares:
  7. - "foo-add-prefix"
  8. rule: "Host(`example.com`)"
  9. middlewares:
  10. foo-add-prefix:
  11. addPrefix:
  12. prefix: "/foo"
  13. services:
  14. service1:
  15. loadBalancer:
  16. servers:
  17. - url: "http://127.0.0.1:80"

Available Middlewares

MiddlewarePurposeArea
AddPrefixAdd a Path PrefixPath Modifier
BasicAuthBasic auth mechanismSecurity, Authentication
BufferingBuffers the request/responseRequest Lifecycle
ChainCombine multiple pieces of middlewareMiddleware tool
CircuitBreakerStop calling unhealthy servicesRequest Lifecycle
CompressCompress the responseContent Modifier
DigestAuthAdds Digest AuthenticationSecurity, Authentication
ErrorsDefine custom error pagesRequest Lifecycle
ForwardAuthAuthentication delegationSecurity, Authentication
HeadersAdd / Update headersSecurity
IPWhiteListLimit the allowed client IPsSecurity, Request lifecycle
InFlightReqLimit the number of simultaneous connectionsSecurity, Request lifecycle
PassTLSClientCertAdding Client Certificates in a HeaderSecurity
RateLimitLimit the call frequencySecurity, Request lifecycle
RedirectSchemeRedirect easily the client elsewhereRequest lifecycle
RedirectRegexRedirect the client elsewhereRequest lifecycle
ReplacePathChange the path of the requestPath Modifier
ReplacePathRegexChange the path of the requestPath Modifier
RetryAutomatically retry the request in case of errorsRequest lifecycle
StripPrefixChange the path of the requestPath Modifier
StripPrefixRegexChange the path of the requestPath Modifier