»Installing Consul API Gateway

This topic describes how to use the Consul API Gateway add-on module. It includes instructions for installation and configuration.

»Requirements

Ensure that the environment you are deploying Consul API Gateway in meets the requirements listed in the Technical Specifications. This includes validating that the requirements for minimum versions of software are met. See the Release Notes for the version of API Gateway you are deploying.

»Installation

NOTE: When you see VERSION in examples of commands or configuration settings, replace VERSION with the version number of the release you are installing, like 0.2.0. If there is a lower case "v" in front of VERSION the version number needs to follow the "v" as is v0.2.0

Issue the following command to install the CRDs:

$ kubectl apply --kustomize="github.com/hashicorp/consul-api-gateway/config/crd?ref=vVERSION"

$ kubectl apply --kustomize="github.com/hashicorp/consul-api-gateway/config/crd?ref=vVERSION"

Create a values.yaml file for your Consul API Gateway deployment. Copy the content below into the values.yaml file. The values.yaml will be used by the Consul Helm chart. Available versions of the Consul and Consul API Gateway Docker images can be found on DockerHub, with additional context on version compatibility published in GitHub releases. See Helm Chart Configuration - apiGateway for more available options on how to configure your Consul API Gateway deployment via the Helm chart.
```
global:
  name: consul
connectInject:
  enabled: true
controller:
  enabled: true
apiGateway:
  enabled: true
  image: hashicorp/consul-api-gateway:VERSION
```
values.yaml
```
global:
  name: consul
connectInject:
  enabled: true
controller:
  enabled: true
apiGateway:
  enabled: true
  image: hashicorp/consul-api-gateway:VERSION
```

Install Consul API Gateway using the standard Consul Helm chart and specify the custom values file. Available versions of the Consul Helm chart can be found in GitHub releases.

$ helm install consul hashicorp/consul --version 0.43.0 --values values.yaml --create-namespace --namespace consul

$ helm install consul hashicorp/consul --version 0.43.0 --values values.yaml --create-namespace --namespace consul

»Usage

Verify that the requirements have been met.
Verify that the Consul API Gateway CRDs and controller have been installed and applied (see Installation).

Configure the artifacts described below in Configuration.

apiGateway:
  managedGatewayClass:
    enabled: true

values.yaml

apiGateway:
  managedGatewayClass:
    enabled: true

Issue the kubectl apply command to implement the configurations, e.g.:

$ kubectl apply -f gateway.yaml routes.yaml

$ kubectl apply -f gateway.yaml routes.yaml

»Configuration

Configure the following artifacts to facilitate ingress into your Consul service mesh:

GatewayClassConfig: Describes additional Consul API Gateway-related configuration parameters for the GatewayClass resource.
GatewayClass: Defines a class of gateway resources that you can use as a template for creating gateways.
Gateway: Defines the main infrastructure resource that links API gateway components. It specifies the name of the GatewayClass and one or more listeners (see Listeners), which specify the logical endpoints bound to the gateway's addresses.
Routes: Specifies the path from the client to the listener.

Note: Add the following managedGatewayClass configuration to the values.yaml Helm configuration to enable the GatewayClassConfig and GatewayClass to be created automatically. The gateway, listeners, and routes will need to be configured manually. When managedGatewayClass is enabled, the serviceType for a managed GatewayClass will also default to LoadBalancer, which is appropriate for most deployments to managed Kubernetes cloud offerings (i.e., EKS, GKE, AKS). Other deployments, such as to a kind cluster, may require specifying NodePort or ClusterIP, instead.

»GatewayClassConfig

The GatewayClassConfig object describes Consul API Gateway-related configuration parameters for the GatewayClass.

Add the kind: GatewayClassConfig option to the gateway values file to declare a gateway class. The following example creates a gateway class configuration called test-gateway-class-config:

apiVersion: api-gateway.consul.hashicorp.com/v1alpha1
kind: GatewayClassConfig
metadata:
  name: test-gateway-class-config
spec:
  useHostPorts: true
  logLevel: 'trace'
  consul:
    scheme: 'https'
    ports:
      http: 8501
      grpc: 8502

gateway.yaml

apiVersion: api-gateway.consul.hashicorp.com/v1alpha1
kind: GatewayClassConfig
metadata:
  name: test-gateway-class-config
spec:
  useHostPorts: true
  logLevel: 'trace'
  consul:
    scheme: 'https'
    ports:
      http: 8501
      grpc: 8502

The following table describes the allowed parameters for the spec array:

Parameter	Description	Type	Default
`consul.address`	Specifies the address of the Consul server to communicate with in the gateway pod. If unspecified, the pod will attempt to use a local agent on the host on which the pod is running.	String	N/A
`consul.authentication.account`	Specifies the Kubernetes service account to use for authentication.	String	N/A
`consul.authentication.managed`	Set to `true` to enable deployments to run with managed service accounts created by the gateway controller. The `consul.authentication.account` field is ignored when this option is enabled.	Boolean	`false`
`consul.authentication.method`	Specifies the Consul auth method used for initial authentication by Consul API Gateway.	String	N/A
`consul.authentication.namespace`	Specifies the Consul namespace to use for authentication.	String	N/A
`consul.ports.grpc`	Specifies the gRPC port for Consul's xDS server.	Integer	`8502`
`consul.ports.http`	Specifies the port for Consul's HTTP server.	Integer	`8500`
`consul.scheme`	Specifies the scheme to use for connecting to Consul. The supported values are `"http"` and `"https"`.	String	`"http"`
`copyAnnotations.service`	List of annotations to copy to the gateway service.	Array	`["external-dns.alpha.kubernetes.io/hostname"]`
`image.consulAPIGateway`	The image to use for consul-api-gateway. View available image tags on DockerHub.	String	`"hashicorp/consul-api-gateway:RELEASE_VERSION"`
`image.envoy`	Specifies the container image to use for Envoy. View available image tags on DockerHub.	String	`"envoyproxy/envoy:RELEASE_VERSION"`
`logLevel`	Specifies the error reporting level for logs. You can specify the following values: `error`, `warning`, `info`, `debug`, `trace`.	String	`"info"`
`nodeSelector`	Specifies a set of parameters that constrain the nodes on which the pod can run. Defining nodes with the `nodeSelector` enables the pod to fit on a node. The selector must match a node's labels for the pod to be scheduled on that node. Refer to the Kubernetes documentation for additional information.	Object	N/A
`serviceType`	Specifies the ingress methods for a service. The following values are supported: `ClusterIP` `NodePort` `LoadBalancer`.	String	N/A
`useHostPorts`	If set to `true`, then the Envoy container ports are mapped to host ports.	Boolean	`false`

Refer to the Consul API Gateway repository for the complete specification.

»GatewayClass

The GatewayClass resource is used as a template for creating Gateway resources. The specification includes the name of the controller (controllerName) and an API object containing controller-specific configuration resources within the cluster (parametersRef). The value of the controllerName field must be set to hashicorp.com/consul-api-gateway-controller.

When gateways are created from a GatewayClass, they use the parameters specified in the GatewayClass at the time of instantiation.

Add the kind: GatewayClass option to the the gateway values file to declare a gateway class. The following example creates a gateway class called test-gateway-class:

apiVersion: gateway.networking.k8s.io/v1alpha2
kind: GatewayClass
metadata:
  name: test-gateway-class
spec:
  controllerName: 'hashicorp.com/consul-api-gateway-controller'
  parametersRef:
    group: api-gateway.consul.hashicorp.com
    kind: GatewayClassConfig
    name: test-gateway-class-config

gateway.yaml

apiVersion: gateway.networking.k8s.io/v1alpha2
kind: GatewayClass
metadata:
  name: test-gateway-class
spec:
  controllerName: 'hashicorp.com/consul-api-gateway-controller'
  parametersRef:
    group: api-gateway.consul.hashicorp.com
    kind: GatewayClassConfig
    name: test-gateway-class-config

Refer to the Kubernetes Gateway API documentation for details about configuring gateway classes.

»Gateway

The gateway configuration is the main infrastructure resource that links API gateway components. It specifies the name of the GatewayClass and one or more listeners.

Add the kind: Gateway option to the configuration file to declare a gateway. The following example creates a gateway called example-gateway. The gateway is based on the test-gateway-class and includes a listener called https (see Listeners for details about the listener configuration).

apiVersion: gateway.networking.k8s.io/v1alpha2
kind: Gateway
metadata:
  name: example-gateway
  annotations:
    'external-dns.alpha.kubernetes.io/hostname': DNS_HOSTNAME
spec:
  gatewayClassName: test-gateway-class
  listeners:
    - protocol: HTTPS
      hostname: DNS_HOSTNAME
      port: 443
      name: https
      allowedRoutes:
        namespaces:
          from: Same
      tls:
        certificateRefs:
          - name: gateway-production-certificate

gateway.yaml

apiVersion: gateway.networking.k8s.io/v1alpha2
kind: Gateway
metadata:
  name: example-gateway
  annotations:
    'external-dns.alpha.kubernetes.io/hostname': DNS_HOSTNAME
spec:
  gatewayClassName: test-gateway-class
  listeners:
    - protocol: HTTPS
      hostname: DNS_HOSTNAME
      port: 443
      name: https
      allowedRoutes:
        namespaces:
          from: Same
      tls:
        certificateRefs:
          - name: gateway-production-certificate

Refer to the Kubernetes Gateway API documentation for details about configuring gateways:

»Listeners

Listeners are the logical endpoints bound to the gateway's addresses. Add the listener object to the gateway configuration and specify the following properties to define a listener:

Parameter	Description	Type	Default
`hostname`	Specifies the virtual hostname to match for protocol types.	String	none
`port`	Specifies the network port number.	Integer	none
`protocol`	Specifies the network protocol expected by the listener.	String	`http`
`tls`	Collection of parameters that specify TLS options for the listener. Refer to the `GatewayTLSConfig` documentation for additional information about configuring TLS.	Object	N/A
`tls.mode`	Specifies a mode for operating Consul API Gateway listeners over TLS. You can only specify the `Terminate` mode, which configures the TLS session between the downstream client and the gateway to terminate at the gateway. Refer to the `TLSModeType` documentation for additional information.	String	`Terminate`
`tls.certificateRefs`	Specifies the name of secret object used for Envoy SDS (Secret Discovery Service) to support terminating TLS. Refer to the `[]*SecretObjectReference` documentation for additional information.	String	N/A
`tls.options`	Specifies key/value pairs to enable extended TLS configuration specific to an implementation.	Object	N/A
`tls.options.tls_min_version`	Specifies the minimum TLS version supported for the listener. The following values are supported: `TLS_AUTO`, `TLSv1_0`, `TLSv1_1`, `TLSv1_2`, `TLSv1_3`.	String	`TLS 1.2`
`tls.options.tls_max_version`	Specifies the maximum TLS version supported for the listener. The specified version must be greater than or equal to `TLSMinVersion`. The following values are supported: `TLS_AUTO`, `TLSv1_0`, `TLSv1_1`, `TLSv1_2`, `TLSv1_3`.	String	`TLS 1.3`
`tls.options.tls_cipher_suites`	Specifies the list of TLS cipher suites to support when negotiating connections using TLS 1.2 or earlier. If unspecified, a more secure set of cipher suites than Envoy's current default server cipher list will be used. The full list of supported cipher suites can seen in `internal/common/tls.go` and is dependent on underlying support in Envoy.	String	See description

Refer to the Kubernetes Gateway API documentation for details about configuring listeners.

»Route

Routes are independent configuration objects that are associated with specific listeners.

Declare a route with either kind: HTTPRoute or kind: TCPRoute and configure the route parameters in the spec block. Refer to the Kubernetes Gateway API documentation for each object type for details:

The following example creates a route named example-route associated with a listener defined in example-gateway.

apiVersion: gateway.networking.k8s.io/v1alpha2
kind: HTTPRoute
metadata:
  name: example-route
spec:
  parentRefs:
    - name: example-gateway
  rules:
    - backendRefs:
        - kind: Service
          name: echo
          port: 8080

routes.yaml

apiVersion: gateway.networking.k8s.io/v1alpha2
kind: HTTPRoute
metadata:
  name: example-route
spec:
  parentRefs:
    - name: example-gateway
  rules:
    - backendRefs:
        - kind: Service
          name: echo
          port: 8080

To create a route for a backendRef in a different namespace, you must also create a ReferencePolicy.

The following example creates a route named example-route in namespace gateway-namespace. This route has a backendRef in namespace service-namespace. Traffic is allowed because the ReferencePolicy, named reference-policy in namespace service-namespace, allows traffic from HTTPRoutes in gateway-namespace to Services in service-namespace.

apiVersion: gateway.networking.k8s.io/v1alpha2
kind: HTTPRoute
metadata:
  name: example-route
  namespace: gateway-namespace
spec:
  parentRefs:
    - name: example-gateway
  rules:
    - backendRefs:
        - kind: Service
          name: echo
          namespace: service-namespace
          port: 8080
---

apiVersion: gateway.networking.k8s.io/v1alpha2
kind: ReferencePolicy
metadata:
  name: reference-policy
  namespace: service-namespace
spec:
  from:
    - group: gateway.networking.k8s.io
      kind: HTTPRoute
      namespace: gateway-namespace
  to:
    - group: ""
      kind: Service
      name: echo

route_with_referencepolicy.yaml

apiVersion: gateway.networking.k8s.io/v1alpha2
kind: HTTPRoute
metadata:
  name: example-route
  namespace: gateway-namespace
spec:
  parentRefs:
    - name: example-gateway
  rules:
    - backendRefs:
        - kind: Service
          name: echo
          namespace: service-namespace
          port: 8080
---

apiVersion: gateway.networking.k8s.io/v1alpha2
kind: ReferencePolicy
metadata:
  name: reference-policy
  namespace: service-namespace
spec:
  from:
    - group: gateway.networking.k8s.io
      kind: HTTPRoute
      namespace: gateway-namespace
  to:
    - group: ""
      kind: Service
      name: echo

»MeshService

The MeshService configuration holds a reference to an externally-managed Consul service mesh service and can be used as a backendRef for a Route.

Parameter	Description	Type	Default
`name`	Specifies the service name for a Consul service. It is assumed this service will exist in either the `consulDestinationNamespace` or mirrored Consul namespace from where this custom resource is defined, depending on the Helm configuration.

Refer to the Consul API Gateway repository for the complete specification.