Android

Scenarios

To use Android to call an API through App authentication, obtain the Android SDK, create a project, and then call the API by referring to the API calling example.

Prerequisites

• You have obtained API calling information. For details, see Preparations.
• You have installed the Android development environment. For details, see Preparations.

Obtaining the SDK

Old version: Log in to the ROMA Connect console, choose API Connect > API Calling > SDKs, and download the SDK.

New version: Log in to the ROMA Connect console, choose API Connect > Credentials > SDKs, and download the SDK.

The following shows the directory structure after the decompression.

Opening the Sample Project

1. Start Android Studio and choose File > Open.

   Select the directory where the SDK is decompressed.

2. View the directory structure of the project shown in the following figure.
   Figure 1 Project directory structure
   

API Calling Example

1. Add required JAR files to the app/libs directory of the Android project. The following JAR files must be included:
   • java-sdk-core-x.x.x.jar
   • joda-time-2.10.jar
2. Add dependencies of the okhttp library to the build.gradle file.
   Add implementation 'com.squareup.okhttp3:okhttp:3.14.2' in the dependencies field of the build.gradle file.

   dependencies {    
       ...
       ...
       implementation 'com.squareup.okhttp3:okhttp:3.14.3'
   }

3. Create a request, enter the key and secret of the authorized credential, and specify the method name, request URL, and body. For details, see Obtaining API Calling Information.

   Request request = new Request();
   try {
   // Directly writing AK/SK in code is risky. For security, encrypt your AK/SK and store them in the configuration file or environment variables. 
   // In this example, the AK/SK are stored in environment variables for identity authentication. Before running this example, set environment variables HUAWEICLOUD_SDK_AK and HUAWEICLOUD_SDK_SK. 
   	request.setKey(System.getenv("HUAWEICLOUD_SDK_AK"));
   	request.setSecrect(System.getenv("HUAWEICLOUD_SDK_SK"));
   	request.setMethod("POST");
   	request.setUrl("https://c967a237-cd6c-470e-906f-a8655461897e.apigw.exampleRegion.com/app1");
   	request.addQueryStringParam("name", "value");
   	request.addHeader("Content-Type", "text/plain");
   	request.setBody("demo");
   } catch (Exception e) {
   	e.printStackTrace();
   	return;
   }

4. Sign the request to generate an okhttp3.Request object for API access.

   okhttp3.Request signedRequest = Client.signOkhttp(request);
   OkHttpClient client = new OkHttpClient.Builder().build();
   Response response = client.newCall(signedRequest).execute();