Usage

This topic describes how to use Consul API Gateway.

Basic usage

Complete the following steps to use Consul API Gateway in your network.

Verify that the requirements have been met.
Verify that the Consul API Gateway CRDs and controller have been installed and applied. Refer to Installation for details.
Configure your Gateway and Routes as describe in the Configuration section.
values.yaml
```
  apiGateway:
    enabled: true
    managedGatewayClass:
```
Issue the kubectl apply command to implement the configurations:
```
  $ kubectl apply -f gateway.yaml routes.yaml
```

Reroute HTTP requests

Configure the following fields in your Route configuration to use this feature. Refer to the Route configuration reference for details about the parameters.

rules.filters.type: Set this parameter to URLRewrite to instruct Consul API Gateway to rewrite the URL when specific conditions are met.
rules.filters.urlRewrite: Specify the path configuration.
rules.filters.urlRewrite.path: Contains the paths that incoming requests should be rewritten to based on the match conditions.

Note that if the route is configured to accept paths with and without a trailing slash, you must make two separate routes to handle each case.

Example

In the following example, requests to /incoming-request-prefix/ are forwarded to the backendRef as /prefix-backend-receives/. A request to /incoming-request-prefix/request-path, for instance, is received by the backendRef as /prefix-backend-receives/request-path.

apiVersion: gateway.networking.k8s.io/v1beta1
kind: HTTPRoute
metadata:
 name: example-route
 ##...
spec:
 parentRefs:
   - group: gateway.networking.k8s.io
     kind: Gateway
     name: api-gateway
 rules:
   - backendRefs:
     . . .
     filters:
       - type: URLRewrite
         urlRewrite:
           path:
             replacePrefixMatch: /prefix-backend-receives/
             type: ReplacePrefixMatch
     matches:
       - path:
           type: PathPrefix
           value: /incoming–request-prefix/

Error Messages

This topic provides information about potential error messages associated with Consul API Gateway. If you receive an error message that does not appear in this section, refer to the following resources:

Helm installation failed: "no matches for kind"

Error: INSTALLATION FAILED: unable to build kubernetes objects from release manifest: [unable to recognize "": no matches for kind "GatewayClass" in version "gateway.networking.k8s.io/v1alpha2", unable to recognize "": no matches for kind "GatewayClassConfig" in version "api-gateway.consul.hashicorp.com/v1alpha1"]

Conditions: Consul API Gateway generates this error when the required CRD files have not been installed in Kubernetes prior to installing Consul API Gateway.

Impact: The installation process typically fails after this error message is generated.

Recommended Action: Install the required CRDs by using the command in Step 1 of the Consul API Gateway installation instructions and then retry installing Consul API Gateway.