Modify the Requests and the Responses

Traefik Hub API Gateway allows you to modify the requests and the responses according to your needs. It is possible to rewrite the path (adding or stripping the prefix or replacing the values), to compress the response, or to manipulate the headers.

---

Add Prefix

Adds the prefix /foo to every request:

Middleware AddPrefix

apiVersion: traefik.io/v1alpha1
kind: Middleware
metadata:
  name: add-foo
  namesapce: apps
spec:
  addPrefix:
    prefix: /foo

IngressRoute

apiVersion: traefik.io/v1alpha1
kind: IngressRoute
metadata:
  name: applications-apigateway-prefix
  namespace: apps
spec:
  entryPoints:
    - websecure
  routes:
  - match: Path(`/addprefix`)
    kind: Rule
    services:
    - name: whoami
      port: 80
    middlewares:
    - name: add-foo

Service & Deployment

kind: Deployment
apiVersion: apps/v1
metadata:
  name: whoami
  namespace: apps
spec:
  replicas: 1
  selector:
    matchLabels:
      app: whoami
  template:
    metadata:
      labels:
        app: whoami
    spec:
      containers:
      - name: whoami
        image: traefik/whoami

---
apiVersion: v1
kind: Service
metadata:
  name: whoami
  namespace: apps
  labels:
    app: whoami
spec:
  type: ClusterIP
  ports:
  - port: 80
    name: whoami
  selector:
    app: whoami

Compress

Compress the response according to the Accept-Encoding header value:

Middleware Compress

apiVersion: traefik.io/v1alpha1
kind: Middleware
metadata:
  name: compress
  namesapce: apps
spec:
  compress: {}

IngressRoute

apiVersion: traefik.io/v1alpha1
kind: IngressRoute
metadata:
  name: applications-apigateway-compress
  namespace: apps
spec:
  entryPoints:
    - websecure
  routes:
  - match: Path(`/compress`)
    kind: Rule
    services:
    - name: whoami
      port: 80
    middlewares:
    - name: compress

Service & Deployment

kind: Deployment
apiVersion: apps/v1
metadata:
  name: whoami
  namespace: apps
spec:
  replicas: 1
  selector:
    matchLabels:
      app: whoami
  template:
    metadata:
      labels:
        app: whoami
    spec:
      containers:
      - name: whoami
        image: traefik/whoami

---
apiVersion: v1
kind: Service
metadata:
  name: whoami
  namespace: apps
  labels:
    app: whoami
spec:
  type: ClusterIP
  ports:
  - port: 80
    name: whoami
  selector:
    app: whoami

Manipulate Headers

Adding Headers to the Request and the Response

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

Middleware Headers

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

IngressRoute

apiVersion: traefik.io/v1alpha1
kind: IngressRoute
metadata:
  name: applications-apigateway-headers
  namespace: apps
spec:
  entryPoints:
    - websecure
  routes:
  - match: Path(`/headers`)
    kind: Rule
    services:
    - name: whoami
      port: 80
    middlewares:
    - name: middleware-header

Service & Deployment

kind: Deployment
apiVersion: apps/v1
metadata:
  name: whoami
  namespace: apps
spec:
  replicas: 1
  selector:
    matchLabels:
      app: whoami
  template:
    metadata:
      labels:
        app: whoami
    spec:
      containers:
      - name: whoami
        image: traefik/whoami

---
apiVersion: v1
kind: Service
metadata:
  name: whoami
  namespace: apps
  labels:
    app: whoami
spec:
  type: ClusterIP
  ports:
  - port: 80
    name: whoami
  selector:
    app: whoami

Adding and Removing Headers

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

Middleware Headers

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

IngressRoute

apiVersion: traefik.io/v1alpha1
kind: IngressRoute
metadata:
  name: applications-apigateway-headers
  namespace: apps
spec:
  entryPoints:
    - websecure
  routes:
  - match: Path(`/headers`)
    kind: Rule
    services:
    - name: whoami
      port: 80
    middlewares:
    - name: middleware-header

Service & Deployment

kind: Deployment
apiVersion: apps/v1
metadata:
  name: whoami
  namespace: apps
spec:
  replicas: 1
  selector:
    matchLabels:
      app: whoami
  template:
    metadata:
      labels:
        app: whoami
    spec:
      containers:
      - name: whoami
        image: traefik/whoami

---
apiVersion: v1
kind: Service
metadata:
  name: whoami
  namespace: apps
  labels:
    app: whoami
spec:
  type: ClusterIP
  ports:
  - port: 80
    name: whoami
  selector:
    app: whoami

Replace Path

Replace the request path with /foo:

Middleware ReplacePath

---
apiVersion: traefik.io/v1alpha1
kind: Middleware
metadata:
  name: middleware-replacepath
spec:
  replacePath:
    path: /foo

IngressRoute

apiVersion: traefik.io/v1alpha1
kind: IngressRoute
metadata:
  name: applications-apigateway-headers
  namespace: apps
spec:
  entryPoints:
    - websecure
  routes:
  - match: Path(`/replacepath`)
    kind: Rule
    services:
    - name: whoami
      port: 80
    middlewares:
    - name: middleware-replacepath

Service & Deployment

kind: Deployment
apiVersion: apps/v1
metadata:
  name: whoami
  namespace: apps
spec:
  replicas: 1
  selector:
    matchLabels:
      app: whoami
  template:
    metadata:
      labels:
        app: whoami
    spec:
      containers:
      - name: whoami
        image: traefik/whoami

---
apiVersion: v1
kind: Service
metadata:
  name: whoami
  namespace: apps
  labels:
    app: whoami
spec:
  type: ClusterIP
  ports:
  - port: 80
    name: whoami
  selector:
    app: whoami

Strip Prefix

It exists two middlewares to strip the prefix:

• StripPrefix: Strip prefixes that are equals to the value given in parameter.
• StripPrefixRegex: Strip prefixes that match the regular expression given in parameter.

In the example below, the middleware strips the prefix /foo/$value with $value being any alphabetic value:

Middleware StripPrefixRegex

apiVersion: traefik.io/v1alpha1
kind: Middleware
metadata:
  name: middleware-stripprefixregex
spec:
  stripPrefixRegex:
    regex:
      - "/foo/[a-z]+"

IngressRoute

apiVersion: traefik.io/v1alpha1
kind: IngressRoute
metadata:
  name: applications-apigateway-headers
  namespace: apps
spec:
  entryPoints:
    - websecure
  routes:
  - match: Path(`/strip`)
    kind: Rule
    services:
    - name: whoami
      port: 80
    middlewares:
    - name: middleware-stripprefixregex

Service & Deployment

kind: Deployment
apiVersion: apps/v1
metadata:
  name: whoami
  namespace: apps
spec:
  replicas: 1
  selector:
    matchLabels:
      app: whoami
  template:
    metadata:
      labels:
        app: whoami
    spec:
      containers:
      - name: whoami
        image: traefik/whoami

---
apiVersion: v1
kind: Service
metadata:
  name: whoami
  namespace: apps
  labels:
    app: whoami
spec:
  type: ClusterIP
  ports:
  - port: 80
    name: whoami
  selector:
    app: whoami

---

Related Content

• See the AddPrefix middleware options in the dedicated section.
• See the Compress middleware options in the dedicated section.
• See the Headers middleware options in the dedicated section.
• See how to secure your APIs using headers.
• See the ReplacePath middleware options in the dedicated section.
• See the ReplacePathRegex middleware options in the dedicated section.
• See the StripPrefix middleware options in the dedicated section.
• See the StripPrefixRegex middleware options in the dedicated section.