Auto Scaling:Auto Scaling SDK for Java: Procedures and usage examples

Step 1: Install Auto Scaling SDK for Java

1. Use one of the following methods to configure Maven in IntelliJ IDEA:

   • Method 1: Use Maven that is integrated in IntelliJ IDEA.

   • Method 2: Download Apache Maven based on your OS and manually configure Maven.

2. Visit Alibaba Cloud SDK Center, enter Auto Scaling in the search box, and obtain the SDK core library of Alibaba Cloud and Auto Scaling Maven project dependencies.

3. Create a Maven project by using one of the following methods:

   • Method 1: Add a Maven project to IntelliJ IDEA.

   • Method 2: Convert an existing project into a Maven project.

     1. Right-click the project that you want to convert and select Add Framework Support....

     2. In the Add Frameworks Support window, select Maven and click OK.

4. In the pom.xml file, create a <dependencies></dependencies> tag and add the following dependencies:

   After you add the dependencies, click the Refresh button in the upper-right corner, or right-click the project name and choose Maven > Reload project to download Maven dependencies to the project.

   Note

   SDK packages are frequently updated. We recommend that you obtain the latest version of dependencies from the Alibaba Cloud SDK official website.

   <dependency>
     <groupId>com.aliyun</groupId>
     <artifactId>tea-openapi</artifactId>
     <version>0.2.8</version>
   </dependency>
   <dependency>
     <groupId>com.aliyun</groupId>
     <artifactId>ess20220222</artifactId>
     <version>1.5.2</version>
   </dependency>
   <dependency>
     <groupId>com.aliyun</groupId>
     <artifactId>credentials-java</artifactId>
     <version>0.2.11</version>
   </dependency>

Step 2: Compile Auto Scaling SDK for Java

In this step, the DescribeScalingInstances operation is used as an example to describe how to compile Auto Scaling SDK for Java.

1. Use the Credentials tool to obtain the AccessKey pair from environment variables.

   Sample code:

   com.aliyun.credentials.Client credentialClient = new com.aliyun.credentials.Client();
   com.aliyun.teaopenapi.models.Config config = new Config();
   config.setCredential(credentialClient);
   config.setEndpoint("ess.aliyuncs.com");

2. Generate the client object.

   Sample code:

   com.aliyun.ess20220222.Client client = new com.aliyun.ess20220222.Client(config);

3. Create a request and use a constructor to generate a default request class.

   The request class is named after the API operation, followed by Request. In this example, the API operation used to query ECS instances in a scaling group is named DescribeScalingInstances. In this case, the request class is named DescribeScalingInstancesRequest.

   DescribeScalingInstancesRequest request = new DescribeScalingInstancesRequest();

4. Configure parameters for the request class.

   Call the setXxx method of the request class to configure the required parameters for the API operation. Parameters in this example:

   • The DescribeScalingInstances operation uses the RegionId parameter to specify the region ID.

   • The DescribeScalingInstances operation uses the InstanceId parameter to specify the ID of the ECS instance in the scaling group that you want to query. In this example, the setInstanceId parameter is set to i-bp15itgtxemxy7v9****, which specifies that the ID of the ECS instance is i-bp15itgtxemxy7v9****.

   request.setInstanceId("i-bp15itgtxemxy7v9****");

5. Call the describeScalingInstancesWithOptions class of the client object to obtain the response to the request.

   Sample code:

   com.aliyun.teautil.models.RuntimeOptions runtime = new com.aliyun.teautil.models.RuntimeOptions();
   DescribeScalingInstancesResponse response = client.describeScalingInstancesWithOptions(request,runtime);

   Note

   For information about the specific procedure, see the Procedure section on the Java tab of Auto Scaling in Alibaba Cloud SDK Center.

Sample code

The following sample code provides an example of a complete code of Auto Scaling SDK for Java:

import com.aliyun.ess20220222.models.DescribeScalingInstancesRequest;
import com.aliyun.ess20220222.models.DescribeScalingInstancesResponse;
import com.aliyun.teaopenapi.models.Config;
import com.google.gson.Gson;
import java.util.ArrayList;
import java.util.List;

public class DescribeScalingInstances {
    public static void main(String[] args) throws Exception {
        com.aliyun.credentials.Client credentialClient = new com.aliyun.credentials.Client();
        com.aliyun.teaopenapi.models.Config config = new Config();
        config.setCredential(credentialClient);
        config.setEndpoint("ess.aliyuncs.com");
        com.aliyun.ess20220222.Client client = new com.aliyun.ess20220222.Client(config);
        DescribeScalingInstancesRequest request = new DescribeScalingInstancesRequest();
        request.setRegionId("cn-hangzhou");
        request.setScalingGroupId("asg-XXXXXXXX");
        request.setScalingConfigurationId("asc-XXXXXXXXX");
        request.setPageNumber(1);
        request.setPageSize(10);

        List<String> instanceIdList = new ArrayList<String>();
        instanceIdList.add("i-XXXXXX");
        request.setInstanceIds(instanceIdList);
        com.aliyun.teautil.models.RuntimeOptions runtime = new com.aliyun.teautil.models.RuntimeOptions();
        DescribeScalingInstancesResponse response = client.describeScalingInstancesWithOptions(request,runtime);
        System.out.println(new Gson().toJson(response));
    }
}

Execution result

Sample success response:

{
    "TotalCount": 2,
    "RequestId": "5E65F238-4B45-54B6-BE15-A34956FA0D96",
    "PageSize": 10,
    "PageNumber": 1,
    "ScalingInstances": {
        "ScalingInstance": [
            {
                "LoadBalancerWeight": 50,
                "CreatedTime": "2022-04-27T03:24:58Z",
                "WarmupState": "NoNeedWarmup",
                "ZoneId": "cn-hangzhou-i",
                "InstanceId": "i-bp1h3dog530vvnqm****",
                "ScalingActivityId": "asa-bp16rgo6477ojn3u****",
                "ScalingGroupId": "asg-bp10uuhy2wbb2tip****",
                "CreationTime": "2022-04-27T03:24Z",
                "HealthStatus": "Healthy",
                "LifecycleState": "Protected",
                "Entrusted": false,
                "CreationType": "Attached"
            },
            {
                "LoadBalancerWeight": 50,
                "CreatedTime": "2022-04-27T06:38:21Z",
                "ZoneId": "cn-hangzhou-i",
                "InstanceId": "i-bp15itgtxemxy7v9****",
                "ScalingActivityId": "asa-bp1ejteup0bntltl****",
                "ScalingGroupId": "asg-bp10uuhy2wbb2tip****",
                "HealthStatus": "Healthy",
                "LifecycleState": "Stopped",
                "CreationType": "AutoCreated",
                "WarmupState": "NoNeedWarmup",
                "CreationTime": "2022-04-27T06:38Z",
                "Entrusted": true,
                "ScalingConfigurationId": "asc-bp1433dp4gktwkmi****"
            }
        ]
    },
    "TotalSpotCount": 0
}

Step 1: Obtain the SDK sample code

You can use Alibaba Cloud OpenAPI Explorer to call Auto Scaling API operations to automatically generate SDK sample code.

1. Click OpenAPI Explorer.

2. Download the complete SDK project by following the steps shown in the following figure: Decompress the downloaded SDK project.

Step 2: Run the SDK sample code

1. Open IntelliJ IDEA, choose File > Open, select the decompressed project folder, and then wait for Maven to automatically install dependencies.

2. Run the sample code

   Double-click Sample. Confirm that no error occurs and run the sample code.

3. View the result.

   You can log on to the Auto Scaling console to view the created scaling group.

Sample code

To view the complete sample code, see SDK Sample Code.