API Gateway:Powerful access capabilities provided by API Gateway for containerized Kubernetes application clusters

Create a K8s cluster and install an Ingress

When you create an ACK managed or Serverless cluster, select ALB Ingress for Ingress in the Component Configurations step. For more information, see Create an ACK managed cluster and Create an ACK Serverless cluster.

Set Source of ALB Instance to Create and Network Type to Private. The system automatically creates a standard Application Load Balancer (ALB) instance with the specified network type and a default HTTP:80 listener.

Create a multi-container service in a cluster

Create a service that consists of two containers in the K8s cluster. Each container runs an Nginx image with container port 80. The service port of the ingress controller is 80.

1. Log on to the ACK console. In the left navigation pane, click Clusters.

2. On the Clusters page, click the name of your cluster. In the left navigation pane, click Workloads > Deployments.

3. On the Deployments page, click Create from YAML. Enter the following Resource Orchestration Service text and click Create.

   apiVersion: apps/v1 
   kind: Deployment
   metadata:
     name: nginx-demo
     labels:
       app: nginx
   spec:
     replicas: 2
     selector:
       matchLabels:
         app: nginx
     template:
       metadata:
         labels:
           app: nginx
       spec:
         containers:
         - name: nginx
           image: anolis-registry.cn-zhangjiakou.cr.aliyuncs.com/openanolis/nginx:1.14.1-8.6
           ports:
           - containerPort: 80
   ---
   apiVersion: v1
   kind: Service
   metadata:
     name: nginx-service
   spec:
     ports:
     - port: 80
       protocol: TCP
       targetPort: 80
     selector:
       app: nginx
     sessionAffinity: None
     type: NodePort 

   Note

   Description:

   • Two containers are created based on an Nginx image, and the container service port is 80. A service named nginx-service is created, and the service port is 80, which maps to the 80 port of the container service.

   • Each container runs an Nginx service. The two containers form a stateless application behind a service named nginx-service. API Gateway cannot access this service yet. You need to create an ingress that routes requests to this service for end-to-end communication.

Create an ingress on the ingress controller that routes requests to a service

Create an ingress for the service so the ingress controller can forward API Gateway requests to the appropriate K8s services. Follow these steps:

1. Log on to the ACK console. In the left navigation pane, click Clusters.

2. On the Clusters page, click the name of your cluster. In the left navigation pane, click Network > Ingresses.

3. Click Create Ingress. In the Rules section, configure the domain name and path mapping and click OK.

   Select ALB Ingress as the gateway type. Enter nginx-ingress for the name and select alb for the Ingress Class. Set the domain to yangtest.com, the path to /, and the matching rule to Prefix. For the service name, select nginx-service and set the port to 80.

Create an access authorization for the VPC of the internal CLB instance

To allow API Gateway to access the internal CLB instance of the ingress controller, configure a VPC access authorization in the API Gateway console.

1. Log on to the ACK console. In the left navigation pane, click Clusters.

2. On the Clusters page, click the name of your cluster. In the left navigation pane, click Network > Ingresses.

3. On the Ingresses page, copy the endpoint.

4. Log on to the ALB console.

5. In the left-side navigation pane, click Overview. In the Resources section, paste the copied endpoint and click the retrieved ALB instance.

6. On the Instance Details tab, copy the VPC ID and the domain name of the ALB instance.

7. Log on to the API Gateway console. In the top navigation bar, select a region. In the left-side navigation pane, choose Manage APIs > VPCs.

8. On the VPC Access Authorizations page, click Create Authorization in the upper-right corner.

9. In the Create VPC Access dialog box, specify the VPC Access Name, VPC Id, Instance ID or IP Address, and Port Number parameters. Then, click Confirm.

Create an API

1. Log on to the API Gateway console. In the left-side navigation pane, choose Manage APIs > API Groups.

2. On the API Groups page, find the created group and click Manage APIs in the Actions column.

3. On the APIs page, click Create API in the upper-right corner.

4. In the Basic Information step of the Create API wizard, configure the following parameters and click Next.

   Set Group to api-k8s, enter nginx-test for API Name, and select No Authentication for Security Certification. Leave the API Options checkboxes unselected and the Description field blank.

5. In the Define API Request step, configure the following parameters and click Next.

   For Protocol, select both HTTP and HTTPS. Enter a Request Path beginning with a forward slash (/). For HTTP Method, select GET. For Request Mode, select Map and Filter Parameters. In the Input Parameter Definition section, you can click Add to add request parameters.

6. In the Define Backend Service step, configure the following parameters and click Next.

   For Backend Configuration, select Custom Backend. For Backend Service Type, select VPC. For VPC Access Authorization Name, select the authorization that you created, such as api-k8s. For Backend Request Path, enter /. For HTTP Method, select GET. Set Timeout to 10000 ms.

   Important

   When you create an API, you can add a constant parameter whose name is host, location is header, and value is the domain name of the ingress configured for the service in the ingress controller.

7. In the Define Response step, configure the parameters on the page based on your business requirements and then click Create.

8. In the message that appears, click Publish.

9. In the Publish API dialog box that appears, set Environment to Release, enter remarks in the Remarks section, and then click Publish.

Debug the API

After the API is created and published, test whether requests reach the K8s cluster from the API Gateway console.

1. Log on to the API Gateway console. In the left-side navigation pane, choose Call APIs > Debug.

2. On the debugging page, select the nginx-test API that you created and click Send Request. If the configuration is successful, a response is returned.

   A successful call returns the HTML source code of the default Nginx welcome page on Anolis OS. The title line Welcome to nginx on Anolis OS! confirms that the backend service is connected and the API is configured correctly.