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# Middlewares
Tweaking the Request
{: .subtitle }
![Overview ](../assets/img/middleware/overview.png )
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Attached to the routers, pieces of middleware are a mean of tweaking the requests before they are sent to your [service ](../routing/services/index.md ) (or before the answer from the services are sent to the clients).
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There are many different available middlewares in Traefik, some can modify the request, the headers, some are in charge of redirections, some add authentication, and so on.
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Pieces of middleware can be combined in chains to fit every scenario.
## Configuration Example
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```yaml tab="Docker"
# As a Docker Label
whoami:
image: containous/whoami # A container that exposes an API to show its IP address
labels:
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- "traefik.http.middlewares.foo-add-prefix.addprefix.prefix=/foo"
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```
```yaml tab="Kubernetes"
# As a Kubernetes Traefik IngressRoute
apiVersion: apiextensions.k8s.io/v1beta1
kind: CustomResourceDefinition
metadata:
name: middlewares.traefik.containo.us
spec:
group: traefik.containo.us
version: v1alpha1
names:
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kind: Middleware
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plural: middlewares
singular: middleware
scope: Namespaced
---
apiVersion: traefik.containo.us/v1alpha1
kind: Middleware
metadata:
name: stripprefix
spec:
stripprefix:
prefixes:
- /stripit
---
apiVersion: traefik.containo.us/v1alpha1
kind: IngressRoute
metadata:
name: ingressroute.crd
spec:
# more fields...
routes:
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# more fields...
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middlewares:
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- name: stripprefix
```
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```json tab="Marathon"
"labels": {
"traefik.http.middlewares.foo-add-prefix.addprefix.prefix": "/foo"
}
```
```yaml tab="Rancher"
# As a Rancher Label
labels:
- "traefik.http.middlewares.foo-add-prefix.addprefix.prefix=/foo"
```
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```toml tab="File"
# As Toml Configuration File
[providers]
[providers.file]
[http.routers]
[http.routers.router1]
Service = "myService"
Middlewares = ["foo-add-prefix"]
Rule = "Host(`example.com`)"
[http.middlewares]
[http.middlewares.foo-add-prefix.AddPrefix]
prefix = "/foo"
[http.services]
[http.services.service1]
[http.services.service1.LoadBalancer]
[[http.services.service1.LoadBalancer.Servers]]
URL = "http://127.0.0.1:80"
Weight = 1
```
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## Advanced Configuration
When you declare a middleware, it lives in its `provider` namespace.
For example, if you declare a middleware using a Docker label, under the hoods, it will reside in the docker `provider` namespace.
If you use multiple `providers` and wish to reference a middleware declared in another `provider` , then you'll have to prefix the middleware name with the `provider` name.
??? abstract "Referencing a Middleware from Another Provider"
Declaring the add-foo-prefix in the file provider.
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```toml
[providers]
[providers.file]
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[http.middlewares]
[http.middlewares.add-foo-prefix.AddPrefix]
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prefix = "/foo"
```
Using the add-foo-prefix middleware from docker.
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```yaml
your-container: #
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image: your-docker-image
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labels:
# Attach file.add-foo-prefix middleware (declared in file)
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- "traefik.http.routers.middlewares=file.add-foo-prefix"
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```
## Available Middlewares
| Middleware | Purpose | Area |
|-------------------------------------------|---------------------------------------------------|-----------------------------|
| [AddPrefix ](addprefix.md ) | Add a Path Prefix | Path Modifier |
| [BasicAuth ](basicauth.md ) | Basic auth mechanism | Security, Authentication |
| [Buffering ](buffering.md ) | Buffers the request/response | Request Lifecycle |
| [Chain ](chain.md ) | Combine multiple pieces of middleware | Middleware tool |
| [CircuitBreaker ](circuitbreaker.md ) | Stop calling unhealthy services | Request Lifecycle |
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| [Compress ](compress.md ) | Compress the response | Content Modifier |
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| [DigestAuth ](digestauth.md ) | Adds Digest Authentication | Security, Authentication |
| [Errors ](errorpages.md ) | Define custom error pages | Request Lifecycle |
| [ForwardAuth ](forwardauth.md ) | Authentication delegation | Security, Authentication |
| [Headers ](headers.md ) | Add / Update headers | Security |
| [IPWhiteList ](ipwhitelist.md ) | Limit the allowed client IPs | Security, Request lifecycle |
| [MaxConnection ](maxconnection.md ) | Limit the number of simultaneous connections | Security, Request lifecycle |
| [PassTLSClientCert ](passtlsclientcert.md ) | TODO | Security |
| [RateLimit ](ratelimit.md ) | Limit the call frequency | Security, Request lifecycle |
| [RedirectScheme ](redirectscheme.md ) | Redirect easily the client elsewhere | Request lifecycle |
| [RedirectRegex ](redirectregex.md ) | Redirect the client elsewhere | Request lifecycle |
| [ReplacePath ](replacepath.md ) | Change the path of the request | Path Modifier |
| [ReplacePathRegex ](replacepathregex.md ) | Change the path of the request | Path Modifier |
| [Retry ](retry.md ) | Automatically retry the request in case of errors | Request lifecycle |
| [StripPrefix ](stripprefix.md ) | Change the path of the request | Path Modifier |
| [StripPrefixRegex ](stripprefixregex.md ) | Change the path of the request | Path Modifier |