This topic describes how to construct parameters and a signature in Java and then send a POST request. The procedure in other programming languages is similar.
CommonRequest call examples
import com.aliyuncs.CommonRequest;
import com.aliyuncs.CommonResponse;
import com.aliyuncs.DefaultAcsClient;
import com.aliyuncs.IAcsClient;
import com.aliyuncs.exceptions.ClientException;
import com.aliyuncs.profile.DefaultProfile;
/**
* The required dependency for this demo is Alibaba Cloud SDK for Java.
* You can install Alibaba Cloud SDK for Java by adding Maven dependencies or downloading Alibaba Cloud SDK for Java.
*
* This demo is a generic Remote Procedure Call (RPC) method.
You can use CommonRequest to call API operations.
* This demo calls the GetTopicList operation of Message Queue for Apache Kafka to query topics.
*/
public class CommonRequestDemo {
// The region ID of your purchased instance.
private static final String REGION_ID = "cn-huhehaote";
// Your AccessKey ID.
private static final String ACCESS_KEY = "LTAI5tHRxaQd8WeJvDFZ****";
// Your AccessKey secret.
private static final String ACCESS_KEY_SECRET = "R1WUTHmTDlCy7J8csQ6bRnaMkY****";
// The region where the instance is deployed.
private static final String SYS_DO_MAIN = "alikafka.cn-huhehaote.aliyuncs.com";
public static void main(String[] args) {
// Create a DefaultAcsClient instance and initialize the instance.
DefaultProfile profile = DefaultProfile.getProfile(
REGION_ID, // Your region ID.
ACCESS_KEY, // Your AccessKey ID.
ACCESS_KEY_SECRET); // Your AccessKey secret.
IAcsClient client = new DefaultAcsClient(profile);
// Create an API request and configure the parameters.
CommonRequest request = new CommonRequest();
// The region where the instance is deployed.
request.setSysDomain(SYS_DO_MAIN);
// The version number of the API.
request.setSysVersion("2019-09-16");
// The name of the operation.
request.setSysAction("GetTopicList");
// The parameters of the operation.
request.putQueryParameter("InstanceId", "alikafka_pre-cn-tl32d052****");
request.putQueryParameter("PageNumber", "1");
request.putQueryParameter("PageSize", "30");
try {
CommonResponse response = client.getCommonResponse(request);
System.out.println(response.getData());
} catch (ClientException e) {
e.printStackTrace();
}
}
}HTTP call examples
private static final String ISO8601_DATE_FORMAT = "yyyy-MM-dd'T'HH:mm:ss'Z'";
private static final String ENCODING = "UTF-8";
private static final String HTTP_METHOD = "POST";
// The ID of the region where the Message Queue for Apache Kafka instance is deployed.
private static final String REGION_ID = "cn-xxxxxx";
private static final String ACCESS_KEY = "xxxxxx";
private static final String ACCESS_KEY_SECRET = "xxxxxx";
public static void main(String[] args) {
try {
// 1. Set parameters.
Map<String, String> parameters = buildCommonParams();
// 2. Sort request parameters in alphabetical order.
String[] sortedKeys = sortParamsToArray(parameters);
// 3. Create a string-to-sign.
String stringToSign = buildSignString(parameters, sortedKeys);
// 4. Calculate the signature.
String signature = calculateSignature(stringToSign);
// 5. Add the signature string to the request as a parameter.
parameters.put("Signature", signature);
// 6. Send the POST request.
String result = post(String.format("http://alikafka.%s.aliyuncs.com/", REGION_ID), parameters);
// 7. Verify the result.
System.out.println(result);
} catch (Throwable throwable) {
throwable.printStackTrace();
}
}
private static Map<String, String> buildCommonParams() {
Map<String, String> parameters = Maps.newHashMap();
// Action: specifies the request method.
// GetInstanceList: queries instances. GetConsumerList: queries consumer groups. GetTopicList: queries topics. GetTopicStatus: queries the status of a topic.
// GetConsumerProgress: queries the status of a consumer group. CreateTopic: creates a topic. CreateConsumerGroup: creates a Group.
parameters.put("Action", "GetInstanceList");
// API version: "2018-10-15".
parameters.put("Version", "2018-10-15");
// Request parameters: RegionId is a required parameter.
// Ensure that all the parameters of the API operation are specified, such as InstanceId, Topic, and ConsumerId.
// parameters.put("InstanceId", "cn-huhehaote");
// parameters.put("Topic", "cn-huhehaote");
// parameters.put("Remark", "cn-huhehaote");
// parameters.put("ConsumerId", "cn-huhehaote");
parameters.put("RegionId", REGION_ID);
parameters.put("AccessKeyId", ACCESS_KEY);
// Timestamp, in the format of yyyy-MM-dd'T'HH:mm:ss'Z'.
parameters.put("Timestamp", formatIso8601Date(new Date()));
parameters.put("SignatureMethod", "HMAC-SHA1");
parameters.put("SignatureVersion", "1.0");
parameters.put("SignatureNonce", UUID.randomUUID().toString());
parameters.put("Format", "json");
return parameters;
}
private static String[] sortParamsToArray(Map<String, String> parameters) {
String[] sortedKeys = parameters.keySet().toArray(new String[]{});
Arrays.sort(sortedKeys);
return sortedKeys;
}
private static String buildSignString(Map<String, String> parameters,
String[] sortedKeys) throws UnsupportedEncodingException {
StringBuilder stringToSign = new StringBuilder();
String SEPARATOR = "&";
stringToSign.append(HTTP_METHOD).append(SEPARATOR);
stringToSign.append(percentEncode("/")).append(SEPARATOR);
StringBuilder canonicalizedQueryString = new StringBuilder();
for(String key : sortedKeys) {
// Encode the key and value.
canonicalizedQueryString.append("&")
.append(percentEncode(key)).append("=")
.append(percentEncode(parameters.get(key)));
}
// Encode the canonicalized query string.
stringToSign.append(percentEncode(canonicalizedQueryString.toString().substring(1)));
return stringToSign.toString();
}
private static String calculateSignature(String stringToSign)
throws NoSuchAlgorithmException, InvalidKeyException, UnsupportedEncodingException {
String ALGORITHM = "HmacSHA1";
String ENCODING = "UTF-8";
// The AccessKey secret of the account.
String accessKeySecret = ACCESS_KEY_SECRET + "&";
Mac mac = Mac.getInstance(ALGORITHM);
mac.init(new SecretKeySpec(accessKeySecret.getBytes(ENCODING), ALGORITHM));
byte[] signData = mac.doFinal(stringToSign.getBytes(ENCODING));
return new String(Base64.getEncoder().encode(signData));
}
private static String percentEncode(String value) throws UnsupportedEncodingException {
return value != null ? URLEncoder.encode(value, ENCODING).replace("+", "%20").replace("*", "%2A").replace("%7E", "~") : null;
}
private static String formatIso8601Date(Date date) {
SimpleDateFormat df = new SimpleDateFormat(ISO8601_DATE_FORMAT);
df.setTimeZone(new SimpleTimeZone(0, "GMT"));
return df.format(date);
}
private static String post(String url, Map<String, String> paramMap) throws IOException {
Form form = Form.form();
for (String key : paramMap.keySet()) {
form.add(key, paramMap.get(key));
}
return Request.Post(url).bodyForm(form.build()).connectTimeout(10000).execute().returnContent().asString();
}