Headers¶

Managing Request/Response headers

Headers

The Headers middleware manages the headers of requests and responses.

A set of forwarded headers are automatically added by default. See the FAQ for more information.

Configuration Examples¶

Adding Headers to the Request and the Response¶

The following example adds the X-Script-Name header to the proxied request and the X-Custom-Response-Header header to the response

Docker

labels:
  - "traefik.http.middlewares.testHeader.headers.customrequestheaders.X-Script-Name=test"
  - "traefik.http.middlewares.testHeader.headers.customresponseheaders.X-Custom-Response-Header=value"

Kubernetes

apiVersion: traefik.io/v1alpha1
kind: Middleware
metadata:
  name: test-header
spec:
  headers:
    customRequestHeaders:
      X-Script-Name: "test"
    customResponseHeaders:
      X-Custom-Response-Header: "value"

Consul Catalog

- "traefik.http.middlewares.testheader.headers.customrequestheaders.X-Script-Name=test"
- "traefik.http.middlewares.testheader.headers.customresponseheaders.X-Custom-Response-Header=value"

Marathon

"labels": {
  "traefik.http.middlewares.testheader.headers.customrequestheaders.X-Script-Name": "test",
  "traefik.http.middlewares.testheader.headers.customresponseheaders.X-Custom-Response-Header": "value"
}

Rancher

labels:
  - "traefik.http.middlewares.testheader.headers.customrequestheaders.X-Script-Name=test"
  - "traefik.http.middlewares.testheader.headers.customresponseheaders.X-Custom-Response-Header=value"

File (YAML)

http:
  middlewares:
    testHeader:
      headers:
        customRequestHeaders:
          X-Script-Name: "test"
        customResponseHeaders:
          X-Custom-Response-Header: "value"

File (TOML)

[http.middlewares]
  [http.middlewares.testHeader.headers]
    [http.middlewares.testHeader.headers.customRequestHeaders]
        X-Script-Name = "test"
    [http.middlewares.testHeader.headers.customResponseHeaders]
        X-Custom-Response-Header = "value"

Adding and Removing Headers¶

In the following example, requests are proxied with an extra X-Script-Name header while their X-Custom-Request-Header header gets stripped, and responses are stripped of their X-Custom-Response-Header header.

Docker

labels:
  - "traefik.http.middlewares.testheader.headers.customrequestheaders.X-Script-Name=test"
  - "traefik.http.middlewares.testheader.headers.customrequestheaders.X-Custom-Request-Header="
  - "traefik.http.middlewares.testheader.headers.customresponseheaders.X-Custom-Response-Header="

Kubernetes

apiVersion: traefik.io/v1alpha1
kind: Middleware
metadata:
  name: test-header
spec:
  headers:
    customRequestHeaders:
      X-Script-Name: "test" # Adds
      X-Custom-Request-Header: "" # Removes
    customResponseHeaders:
      X-Custom-Response-Header: "" # Removes

Consul Catalog

- "traefik.http.middlewares.testheader.headers.customrequestheaders.X-Script-Name=test"
- "traefik.http.middlewares.testheader.headers.customrequestheaders.X-Custom-Request-Header="
- "traefik.http.middlewares.testheader.headers.customresponseheaders.X-Custom-Response-Header="

Marathon

"labels": {
  "traefik.http.middlewares.testheader.headers.customrequestheaders.X-Script-Name": "test",
  "traefik.http.middlewares.testheader.headers.customrequestheaders.X-Custom-Request-Header": "",
  "traefik.http.middlewares.testheader.headers.customresponseheaders.X-Custom-Response-Header": "",
}

Rancher

labels:
  - "traefik.http.middlewares.testheader.headers.customrequestheaders.X-Script-Name=test"
  - "traefik.http.middlewares.testheader.headers.customrequestheaders.X-Custom-Request-Header="
  - "traefik.http.middlewares.testheader.headers.customresponseheaders.X-Custom-Response-Header="

File (YAML)

http:
  middlewares:
    testHeader:
      headers:
        customRequestHeaders:
          X-Script-Name: "test" # Adds
          X-Custom-Request-Header: "" # Removes
        customResponseHeaders:
          X-Custom-Response-Header: "" # Removes

File (TOML)

[http.middlewares]
  [http.middlewares.testHeader.headers]
    [http.middlewares.testHeader.headers.customRequestHeaders]
        X-Script-Name = "test" # Adds
        X-Custom-Request-Header = "" # Removes
    [http.middlewares.testHeader.headers.customResponseHeaders]
        X-Custom-Response-Header = "" # Removes

Using Security Headers¶

Security-related headers (HSTS headers, Browser XSS filter, etc) can be managed similarly to custom headers as shown above. This functionality makes it possible to easily use security features by adding headers.

Docker

labels:
  - "traefik.http.middlewares.testHeader.headers.framedeny=true"
  - "traefik.http.middlewares.testHeader.headers.browserxssfilter=true"

Kubernetes

apiVersion: traefik.io/v1alpha1
kind: Middleware
metadata:
  name: test-header
spec:
  headers:
    frameDeny: true
    browserXssFilter: true

Consul Catalog

- "traefik.http.middlewares.testheader.headers.framedeny=true"
- "traefik.http.middlewares.testheader.headers.browserxssfilter=true"

Marathon

"labels": {
  "traefik.http.middlewares.testheader.headers.framedeny": "true",
  "traefik.http.middlewares.testheader.headers.browserxssfilter": "true"
}

Rancher

labels:
  - "traefik.http.middlewares.testheader.headers.framedeny=true"
  - "traefik.http.middlewares.testheader.headers.browserxssfilter=true"

File (YAML)

http:
  middlewares:
    testHeader:
      headers:
        frameDeny: true
        browserXssFilter: true

File (TOML)

[http.middlewares]
  [http.middlewares.testHeader.headers]
    frameDeny = true
    browserXssFilter = true

CORS Headers¶

CORS (Cross-Origin Resource Sharing) headers can be added and configured in a manner similar to the custom headers above. This functionality allows for more advanced security features to quickly be set. If CORS headers are set, then the middleware does not pass preflight requests to any service, instead the response will be generated and sent back to the client directly.
Please note that the example below is by no means authoritative or exhaustive, and should not be used as is for production.

Docker

labels:
  - "traefik.http.middlewares.testheader.headers.accesscontrolallowmethods=GET,OPTIONS,PUT"
  - "traefik.http.middlewares.testheader.headers.accesscontrolallowheaders=*"
  - "traefik.http.middlewares.testheader.headers.accesscontrolalloworiginlist=https://foo.bar.org,https://example.org"
  - "traefik.http.middlewares.testheader.headers.accesscontrolmaxage=100"
  - "traefik.http.middlewares.testheader.headers.addvaryheader=true"

Kubernetes

apiVersion: traefik.io/v1alpha1
kind: Middleware
metadata:
  name: test-header
spec:
  headers:
    accessControlAllowMethods:
      - "GET"
      - "OPTIONS"
      - "PUT"
    accessControlAllowHeaders:
      - "*"
    accessControlAllowOriginList:
      - "https://foo.bar.org"
      - "https://example.org"
    accessControlMaxAge: 100
    addVaryHeader: true

Consul Catalog

- "traefik.http.middlewares.testheader.headers.accesscontrolallowmethods=GET,OPTIONS,PUT"
- "traefik.http.middlewares.testheader.headers.accesscontrolallowheaders=*"
- "traefik.http.middlewares.testheader.headers.accesscontrolalloworiginlist=https://foo.bar.org,https://example.org"
- "traefik.http.middlewares.testheader.headers.accesscontrolmaxage=100"
- "traefik.http.middlewares.testheader.headers.addvaryheader=true"

Marathon

"labels": {
  "traefik.http.middlewares.testheader.headers.accesscontrolallowmethods": "GET,OPTIONS,PUT",
  "traefik.http.middlewares.testheader.headers.accesscontrolallowheaders=*",
  "traefik.http.middlewares.testheader.headers.accesscontrolalloworiginlist": "https://foo.bar.org,https://example.org",
  "traefik.http.middlewares.testheader.headers.accesscontrolmaxage": "100",
  "traefik.http.middlewares.testheader.headers.addvaryheader": "true"
}

Rancher

labels:
  - "traefik.http.middlewares.testheader.headers.accesscontrolallowmethods=GET,OPTIONS,PUT"
  - "traefik.http.middlewares.testheader.headers.accesscontrolallowheaders=*"
  - "traefik.http.middlewares.testheader.headers.accesscontrolalloworiginlist=https://foo.bar.org,https://example.org"
  - "traefik.http.middlewares.testheader.headers.accesscontrolmaxage=100"
  - "traefik.http.middlewares.testheader.headers.addvaryheader=true"

File (YAML)

http:
  middlewares:
    testHeader:
      headers:
        accessControlAllowMethods:
          - GET
          - OPTIONS
          - PUT
        accessControlAllowHeaders: "*"
        accessControlAllowOriginList:
          - https://foo.bar.org
          - https://example.org
        accessControlMaxAge: 100
        addVaryHeader: true

File (TOML)

[http.middlewares]
  [http.middlewares.testHeader.headers]
    accessControlAllowMethods = ["GET", "OPTIONS", "PUT"]
    accessControlAllowHeaders = [ "*" ]
    accessControlAllowOriginList = ["https://foo.bar.org","https://example.org"]
    accessControlMaxAge = 100
    addVaryHeader = true

Configuration Options¶

General¶

Warning

Custom headers will overwrite existing headers if they have identical names.

The detailed documentation for security headers can be found in unrolled/secure.

`customRequestHeaders`¶

The customRequestHeaders option lists the header names and values to apply to the request.

`customResponseHeaders`¶

The customResponseHeaders option lists the header names and values to apply to the response.

`accessControlAllowCredentials`¶

The accessControlAllowCredentials indicates whether the request can include user credentials.

`accessControlAllowHeaders`¶

The accessControlAllowHeaders indicates which header field names can be used as part of the request.

`accessControlAllowMethods`¶

The accessControlAllowMethods indicates which methods can be used during requests.

`accessControlAllowOriginList`¶

The accessControlAllowOriginList indicates whether a resource can be shared by returning different values.

A wildcard origin * can also be configured, and matches all requests. If this value is set by a backend service, it will be overwritten by Traefik.

This value can contain a list of allowed origins.

More information including how to use the settings can be found at:

Traefik no longer supports the null value, as it is no longer recommended as a return value.

`accessControlAllowOriginListRegex`¶

The accessControlAllowOriginListRegex option is the counterpart of the accessControlAllowOriginList option with regular expressions instead of origin values. It allows all origins that contain any match of a regular expression in the accessControlAllowOriginList.

Tip

Regular expressions and replacements can be tested using online tools such as Go Playground or the Regex101.

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

`accessControlExposeHeaders`¶

The accessControlExposeHeaders indicates which headers are safe to expose to the api of a CORS API specification.

`accessControlMaxAge`¶

The accessControlMaxAge indicates how many seconds a preflight request can be cached for.

`addVaryHeader`¶

The addVaryHeader is used in conjunction with accessControlAllowOriginList to determine whether the Vary header should be added or modified to demonstrate that server responses can differ based on the value of the origin header.

`allowedHosts`¶

The allowedHosts option lists fully qualified domain names that are allowed.

`hostsProxyHeaders`¶

The hostsProxyHeaders option is a set of header keys that may hold a proxied hostname value for the request.

`sslRedirect`¶

Warning

Deprecated in favor of EntryPoint redirection or the RedirectScheme middleware.

The sslRedirect only allow HTTPS requests when set to true.

`sslTemporaryRedirect`¶

Warning

Deprecated in favor of EntryPoint redirection or the RedirectScheme middleware.

Set sslTemporaryRedirect to true to force an SSL redirection using a 302 (instead of a 301).

`sslHost`¶

Warning

Deprecated in favor of the RedirectRegex middleware.

The sslHost option is the host name that is used to redirect HTTP requests to HTTPS.

`sslProxyHeaders`¶

The sslProxyHeaders option is set of header keys with associated values that would indicate a valid HTTPS request. It can be useful when using other proxies (example: "X-Forwarded-Proto": "https").

`sslForceHost`¶

Warning

Deprecated in favor of the RedirectRegex middleware.

Set sslForceHost to true and set sslHost to force requests to use SSLHost regardless of whether they already use SSL.

`stsSeconds`¶

The stsSeconds is the max-age of the Strict-Transport-Security header. If set to 0, the header is not set.

`stsIncludeSubdomains`¶

If the stsIncludeSubdomains is set to true, the includeSubDomains directive is appended to the Strict-Transport-Security header.

`stsPreload`¶

Set stsPreload to true to have the preload flag appended to the Strict-Transport-Security header.

`forceSTSHeader`¶

Set forceSTSHeader to true to add the STS header even when the connection is HTTP.

`frameDeny`¶

Set frameDeny to true to add the X-Frame-Options header with the value of DENY.

`customFrameOptionsValue`¶

The customFrameOptionsValue allows the X-Frame-Options header value to be set with a custom value. This overrides the FrameDeny option.

`contentTypeNosniff`¶

Set contentTypeNosniff to true to add the X-Content-Type-Options header with the value nosniff.

`browserXssFilter`¶

Set browserXssFilter to true to add the X-XSS-Protection header with the value 1; mode=block.

`customBrowserXSSValue`¶

The customBrowserXssValue option allows the X-XSS-Protection header value to be set with a custom value. This overrides the BrowserXssFilter option.

`contentSecurityPolicy`¶

The contentSecurityPolicy option allows the Content-Security-Policy header value to be set with a custom value.

`publicKey`¶

The publicKey implements HPKP to prevent MITM attacks with forged certificates.

`referrerPolicy`¶

The referrerPolicy allows sites to control whether browsers forward the Referer header to other sites.

`featurePolicy`¶

Warning

Deprecated in favor of permissionsPolicy

The featurePolicy allows sites to control browser features.

`permissionsPolicy`¶

The permissionsPolicy allows sites to control browser features.

`isDevelopment`¶

Set isDevelopment to true when developing to mitigate the unwanted effects of the AllowedHosts, SSL, and STS options. Usually testing takes place using HTTP, not HTTPS, and on localhost, not your production domain. If you would like your development environment to mimic production with complete Host blocking, SSL redirects, and STS headers, leave this as false.

Using Traefik for Business Applications?

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API Management
Explore // Watch Demo Video
API Gateway
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Ingress Controller
Kubernetes // Docker Swarm

These tools help businesses discover, deploy, secure, and manage microservices and APIs easily, at scale, across any environment.

Headers¶

Configuration Examples¶

Adding Headers to the Request and the Response¶

Adding and Removing Headers¶

Using Security Headers¶

CORS Headers¶

Configuration Options¶

General¶

customRequestHeaders¶

customResponseHeaders¶

accessControlAllowCredentials¶

accessControlAllowHeaders¶

accessControlAllowMethods¶

accessControlAllowOriginList¶

accessControlAllowOriginListRegex¶

accessControlExposeHeaders¶

accessControlMaxAge¶

addVaryHeader¶

allowedHosts¶

hostsProxyHeaders¶

sslRedirect¶

sslTemporaryRedirect¶

sslHost¶

sslProxyHeaders¶

sslForceHost¶

stsSeconds¶

stsIncludeSubdomains¶

stsPreload¶

forceSTSHeader¶

frameDeny¶

customFrameOptionsValue¶

contentTypeNosniff¶

browserXssFilter¶

customBrowserXSSValue¶

contentSecurityPolicy¶

publicKey¶

referrerPolicy¶

featurePolicy¶

permissionsPolicy¶

isDevelopment¶

`customRequestHeaders`¶

`customResponseHeaders`¶

`accessControlAllowCredentials`¶

`accessControlAllowHeaders`¶

`accessControlAllowMethods`¶

`accessControlAllowOriginList`¶

`accessControlAllowOriginListRegex`¶

`accessControlExposeHeaders`¶

`accessControlMaxAge`¶

`addVaryHeader`¶

`allowedHosts`¶

`hostsProxyHeaders`¶

`sslRedirect`¶

`sslTemporaryRedirect`¶

`sslHost`¶

`sslProxyHeaders`¶

`sslForceHost`¶

`stsSeconds`¶

`stsIncludeSubdomains`¶

`stsPreload`¶

`forceSTSHeader`¶

`frameDeny`¶

`customFrameOptionsValue`¶

`contentTypeNosniff`¶

`browserXssFilter`¶

`customBrowserXSSValue`¶

`contentSecurityPolicy`¶

`publicKey`¶

`referrerPolicy`¶

`featurePolicy`¶

`permissionsPolicy`¶

`isDevelopment`¶