Path redirects

Redirect requests to a different path prefix.

For more information, see the Kubernetes Gateway API documentation.

Before you begin

  1. Follow the Get started guide to install kgateway.

  2. Follow the Sample app guide to create a gateway proxy with an HTTP listener and deploy the httpbin sample app.

  3. Get the external address of the gateway and save it in an environment variable. 

    export INGRESS_GW_ADDRESS=$(kubectl get svc -n kgateway-system http -o jsonpath="{.status.loadBalancer.ingress[0]['hostname','ip']}")
echo $INGRESS_GW_ADDRESS  
    kubectl port-forward deployment/http -n kgateway-system 8080:8080

Set up path redirects

Path redirects use the HTTP path modifier to replace either an entire path or path prefixes.

Replace prefix path

  1. Create an HTTPRoute for the httpbin app. In the following example, requests to the /get path are redirected to the /status/200 path, and a 302 HTTP response code is returned to the user.

    Because the ReplacePrefixPath path modifier is used, only the path prefix is replaced during the redirect. For example, requests to http://path.redirect.example/get result in the https://path.redirect.example/status/200 redirect location. However, for longer paths, such as in http://path.redirect.example/get/headers, only the prefix is replaced and a redirect location of https://path.redirect.example/status/200/headers is returned.

    kubectl apply -f- <<EOF
apiVersion: gateway.networking.k8s.io/v1
kind: HTTPRoute
metadata:
  name: httpbin-redirect
  namespace: httpbin
spec:
  parentRefs:
    - name: http
      namespace: kgateway-system
  hostnames:
    - path.redirect.example
  rules:
    - matches:
        - path:
            type: PathPrefix
            value: /get
      filters:
        - type: RequestRedirect
          requestRedirect:
            path:
              type: ReplacePrefixMatch
              replacePrefixMatch: /status/200
            statusCode: 302
EOF
    Setting Description
    spec.parentRefs.name
    spec.parentRefs.namespace    		 The name and namespace of the Gateway resource that serves the route. In this example, you use the Gateway that you created earlier.
    spec.hostnames The hostname for which you want to apply the redirect.
    spec.rules.matches.path The prefix path that you want to redirect. In this example, you want to redirect all requests to the /get path.
    spec.rules.filters.type The type of filter that you want to apply to incoming requests. In this example, the RequestRedirect is used.
    spec.rules.filters.requestRedirect.path.type The type of path modifier that you want to apply. In this example, you want to replace only the prefix path.
    spec.rules.filters.requestRedirect.path.replacePrefixPath The prefix path you want to redirect to. In this example, all requests to the /get prefix path are redirected to the /status/200 prefix path.
    spec.rules.filters.requestRedirect.statusCode The HTTP status code that you want to return to the client in case of a redirect. For non-permanent redirects, use the 302 HTTP response code.

  2. Send a request to the httpbin app on the path.redirect.example domain. Verify that you get back a 302 HTTP response code and the path.redirect.example:8080/status/200 redirect location. 

    curl -vi http://$INGRESS_GW_ADDRESS:8080/get -H "host: path.redirect.example:8080"
    curl -vi localhost:8080/get -H "host: path.redirect.example"

    Example output:

    * Mark bundle as not supporting multiuse
< HTTP/1.1 302 Found
HTTP/1.1 302 Found
< location: http://path.redirect.example:8080/status/200
location: http://path.redirect.example:8080/status/200
< server: envoy
server: envoy
< content-length: 0
content-length: 0

  3. Send another request to the httpbin app on the path.redirect.example domain. This time, you send the request to the /get/headers path. Verify that you get back a 302 HTTP response code and the redirect location path.redirect.example:8080/status/200/headers. 

    curl -vi http://$INGRESS_GW_ADDRESS:8080/get/headers -H "host: path.redirect.example:8080"
    curl -vi localhost:8080/get/headers -H "host: path.redirect.example"

    Example output:

    * Mark bundle as not supporting multiuse
< HTTP/1.1 302 Found
HTTP/1.1 302 Found
< location: http://path.redirect.example:8080/status/200/headers
location: http://path.redirect.example:8080/status/200/headers
< server: envoy
server: envoy
< content-length: 0
content-length: 0

Replace full path

  1. Create an HTTPRoute for the httpbin app. In the following example, requests to the /get path are redirected to the /status/200 path, and a 302 HTTP response code is returned to the user.

    Because the ReplaceFullPath path modifier is used, requests to http://path.redirect.example/get and http://path.redirect.example/get/headers both receive https://path.redirect.example/status/200 as the redirect location.

    kubectl apply -f- <<EOF
apiVersion: gateway.networking.k8s.io/v1
kind: HTTPRoute
metadata:
  name: httpbin-redirect
  namespace: httpbin
spec:
  parentRefs:
    - name: http
      namespace: kgateway-system
  hostnames:
    - path.redirect.example
  rules:
    - matches:
        - path:
            type: PathPrefix
            value: /get
      filters:
        - type: RequestRedirect
          requestRedirect:
            path:
              type: ReplaceFullPath
              replaceFullPath: /status/200
            statusCode: 302
EOF
    Setting Description
    spec.parentRefs.name
    spec.parentRefs.namespace    		 The name and namespace of the Gateway resource that serves the route. In this example, you use the Gateway that you created earlier.
    spec.hostnames The hostname for which you want to apply the redirect.
    spec.rules.matches.path The prefix path that you want to redirect. In this example, you want to redirect all requests to the /get path.
    spec.rules.filters.type The type of filter that you want to apply to incoming requests. In this example, the RequestRedirect is used.
    spec.rules.filters.requestRedirect.path.type The type of path modifier that you want to apply. In this example, you want to replace the full path..
    spec.rules.filters.requestRedirect.path.replaceFullPath The path that you want to redirect to. In this example, all requests to the /get prefix path are redirected to the /status/200 prefix path.
    spec.rules.filters.requestRedirect.statusCode The HTTP status code that you want to return to the client in case of a redirect. For non-permanent redirects, use the 302 HTTP response code.

  2. Send a request to the httpbin app on the path.redirect.example domain. Verify that you get back a 302 HTTP response code and the redirect location path.redirect.example:8080/status/200. 

    curl -vi http://$INGRESS_GW_ADDRESS:8080/get -H "host: path.redirect.example:8080"
    curl -vi localhost:8080/get -H "host: path.redirect.example"

    Example output:

    * Mark bundle as not supporting multiuse
< HTTP/1.1 302 Found
HTTP/1.1 302 Found
< location: http://path.redirect.example:8080/status/200
location: http://path.redirect.example:8080/status/200
< server: envoy
server: envoy
< content-length: 0
content-length: 0

  3. Send another request to the httpbin app on the path.redirect.example domain. This time, you send the request to the /get/headers path. Verify that you get back a 302 HTTP response code and the same redirect location as in the previous example (path.redirect.example:8080/status/200). 

    curl -vi http://$INGRESS_GW_ADDRESS:8080/get/headers -H "host: path.redirect.example:8080"
    curl -vi localhost:8080/get/headers -H "host: path.redirect.example"

    Example output:

    * Mark bundle as not supporting multiuse
< HTTP/1.1 302 Found
HTTP/1.1 302 Found
< location: http://path.redirect.example:8080/status/200
location: http://path.redirect.example:8080/status/200
< server: envoy
server: envoy
< content-length: 0
content-length: 0

Cleanup

You can remove the resources that you created in this guide. 
kubectl delete httproute httpbin-redirect -n httpbin
Host redirect