Alibaba Cloud SDK:Request syntax and signature method V2 for ROA-style APIs

Java

To use the signature method in Java, you must add the following Maven dependencies to the pom.xml file:

<dependency>
    <groupId>org.apache.httpcomponents</groupId>
    <artifactId>httpclient</artifactId>
    <version>4.5.13</version>
</dependency>
<dependency>
     <groupId>com.google.code.gson</groupId>
     <artifactId>gson</artifactId>
     <version>2.9.0</version>
 </dependency>

import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import org.apache.http.client.methods.*;
import org.apache.http.client.utils.URIBuilder;
import org.apache.http.entity.ByteArrayEntity;
import org.apache.http.entity.ContentType;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;

import javax.crypto.Mac;
import javax.crypto.spec.SecretKeySpec;
import javax.xml.bind.DatatypeConverter;
import java.io.IOException;
import java.net.URISyntaxException;
import java.nio.charset.StandardCharsets;
import java.security.InvalidKeyException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.text.SimpleDateFormat;
import java.util.*;


public class SignatureDemo {
    public static class SignatureRequest {
        private final String httpMethod;
        private final String host;
        private final String version;
        private final String canonicalUri;

        public TreeMap<String, String> headers = new TreeMap<>();
        public TreeMap<String, Object> queryParams = new TreeMap<>();
        public byte[] bodyByteArray;

        public SignatureRequest(String httpMethod, String host, String version, String canonicalUri) {
            this.httpMethod = httpMethod;
            this.host = host;
            this.version = version;
            this.canonicalUri = canonicalUri;
            initHeaders();
        }

        private void initHeaders() {
            headers.put("Host", host);
            headers.put("x-acs-version", version);
            headers.put("x-acs-signature-version", "1.0");
            headers.put("Accept", "application/json");
            headers.put("x-acs-signature-nonce", java.util.UUID.randomUUID().toString());
            headers.put("Date", getGmtDate());
            headers.put("x-acs-signature-method", "HMAC-SHA1");
        }

        private String getGmtDate() {
            SimpleDateFormat gmtFormat = new SimpleDateFormat("EEE, dd MMM yyyy HH:mm:ss 'GMT'", Locale.ENGLISH);
            gmtFormat.setTimeZone(TimeZone.getTimeZone("GMT"));
            return gmtFormat.format(new Date());
        }

        public void setBody(Map<String, String> body, ContentType contentType) {
            Gson gson = (new GsonBuilder()).disableHtmlEscaping().create();
            this.bodyByteArray = gson.toJson(body).getBytes(StandardCharsets.UTF_8);
            headers.put("Content-MD5", md5Sum(this.bodyByteArray));
            headers.put("Content-Type", contentType.getMimeType());
        }
    }

    private static final String ACCESS_KEY_ID = System.getenv("ALIBABA_CLOUD_ACCESS_KEY_ID");
    private static final String ACCESS_KEY_SECRET = System.getenv("ALIBABA_CLOUD_ACCESS_KEY_SECRET");
    private static final String ALGORITHM_NAME = "HmacSHA1";

    public static void main(String[] args) {
        // Example 1: Send a POST request.
        String method = "POST";
        String host = "bailian.cn-beijing.aliyuncs.com";
        String version = "2023-12-29";
        String canonicalUri = "/llm-p2e4XXXXXXXXsvtn/datacenter/category";
        SignatureRequest signatureRequest = new SignatureRequest(method, host, version, canonicalUri);
        Map<String, String> body = new HashMap<>();
        body.put("CategoryName", "test");
        body.put("CategoryType", "UNSTRUCTURED");
        System.out.println(new Gson().toJson(body));
        signatureRequest.setBody(body, ContentType.APPLICATION_JSON);

        /*// Example 2: Send a GET request.
        String method = "GET";
        String host = "bailian.cn-beijing.aliyuncs.com";
        String version = "2023-12-29";
        String canonicalUri = "/llm-p2e4XXXXXXXXsvtn/datacenter/files";
        SignatureRequest signatureRequest = new SignatureRequest(method, host, version, canonicalUri);
        signatureRequest.queryParams.put("CategoryId", "cate_a946*********************_10045991");*/

        /*// Example 3: Send a DELETE request.
        String method = "DELETE";
        String host = "bailian.cn-beijing.aliyuncs.com";
        String version = "2023-12-29";
        String canonicalUri = "/llm-p2e4XXXXXXXXsvtn/datacenter/category/cate_a946*********************_10045991";
        SignatureRequest signatureRequest = new SignatureRequest(method, host,  version, canonicalUri);*/

        // Construct the value of the Authorization header.
        generateSignature(signatureRequest);
        // Use HTTPClient to send the request.
        callApi(signatureRequest);
    }

    private static void generateSignature(SignatureRequest signatureRequest) {
        try {
            // Step 1: Construct a canonicalized header
            String canonicalHeaders = buildCanonicalHeaders(signatureRequest);
            // Step 2: Construct a canonicalized resource
            String canonicalQueryString = buildQueryString(signatureRequest);
            // Step 3: Construct a string-to-sign
            String stringToSign = buildStringToSign(signatureRequest, canonicalQueryString, canonicalHeaders);
            // Step 4: Calculate the signature string
            String signature = signString(stringToSign);
            // Step 5: Specify the Authorization header.
            String authorization = "acs " + ACCESS_KEY_ID + ":" + signature;
            signatureRequest.headers.put("Authorization", authorization);
        } catch (Exception ex) {
            throw new IllegalArgumentException(ex.toString());
        }
    }

    private static void callApi(SignatureRequest signatureRequest) {
        try {
            // Send the request by using HttpClient.
            String url = "https://" + signatureRequest.host + signatureRequest.canonicalUri;
            URIBuilder uriBuilder = new URIBuilder(url);
            // Specify request parameters.
            signatureRequest.queryParams.forEach((key, value) -> uriBuilder.addParameter(key, String.valueOf(value)));
            HttpUriRequest httpRequest;
            switch (signatureRequest.httpMethod) {
                case "GET":
                    httpRequest = new HttpGet(uriBuilder.build());
                    break;
                case "POST":
                    HttpPost httpPost = new HttpPost(uriBuilder.build());
                    if (signatureRequest.bodyByteArray != null) {
                        httpPost.setEntity(new ByteArrayEntity(signatureRequest.bodyByteArray, ContentType.create(signatureRequest.headers.get("Content-Type"))));
                    }
                    httpRequest = httpPost;
                    break;
                case "PUT":
                    HttpPut httpPut = new HttpPut(uriBuilder.build());
                    if (signatureRequest.bodyByteArray != null) {
                        httpPut.setEntity(new ByteArrayEntity(signatureRequest.bodyByteArray, ContentType.create(signatureRequest.headers.get("Content-Type"))));
                    }
                    httpRequest = httpPut;
                    break;
                case "DELETE":
                    httpRequest = new HttpDelete(uriBuilder.build());
                    break;
                default:
                    System.out.println("Unsupported HTTP method: " + signatureRequest.httpMethod);
                    throw new IllegalArgumentException("Unsupported HTTP method");
            }
            // Specify HTTP request headers.
            signatureRequest.headers.forEach(httpRequest::addHeader);
            // Send the request.
            try (CloseableHttpClient httpClient = HttpClients.createDefault(); CloseableHttpResponse response = httpClient.execute(httpRequest)) {
                String result = EntityUtils.toString(response.getEntity(), "UTF-8");
                System.out.println(result);
            } catch (IOException e) {
                // Handle errors.
                System.out.println("Failed to send request");
                throw new IllegalArgumentException(e.toString());
            }
        } catch (URISyntaxException e) {
            // Handle errors.
            System.out.println("Invalid URI syntax");
            throw new IllegalArgumentException(e.toString());
        }
    }

    private static String buildCanonicalHeaders(SignatureRequest signatureRequest) {
        StringBuilder canonicalHeaders = new StringBuilder();
        signatureRequest.headers.entrySet().stream()
                .filter(entry -> entry.getKey().startsWith("x-acs-"))
                .forEach(entry -> canonicalHeaders.append(entry.getKey().toLowerCase().trim()).append(":").append(entry.getValue().trim()).append("\n"));
        return canonicalHeaders.toString();
    }

    private static String buildQueryString(SignatureRequest signatureRequest) {
        StringBuilder queryBuilder = new StringBuilder(signatureRequest.canonicalUri);
        if (!signatureRequest.queryParams.isEmpty()) {
            queryBuilder.append("?");
        }

        for (Map.Entry<String, Object> entry : signatureRequest.queryParams.entrySet()) {
            queryBuilder.append(entry.getKey());
            String value = (String) entry.getValue();
            if (value != null && !value.isEmpty()) {
                queryBuilder.append("=").append(value).append("&");
            } else {
                queryBuilder.append("&");
            }
        }
        String queryString = queryBuilder.toString();
        if (queryString.endsWith("&")) {
            queryString = queryString.substring(0, queryString.length() - 1);
        }
        return queryString;
    }

    private static String buildStringToSign(SignatureRequest signatureRequest, String canonicalQueryString, String canonicalHeaders) {
        StringBuilder sb = new StringBuilder();
        sb.append(signatureRequest.httpMethod).append("\n");
        appendIfPresent(sb, signatureRequest.headers.get("Accept"));
        appendIfPresent(sb, signatureRequest.headers.get("Content-MD5"));
        appendIfPresent(sb, signatureRequest.headers.get("Content-Type"));
        appendIfPresent(sb, signatureRequest.headers.get("Date"));
        sb.append(canonicalHeaders);
        sb.append(canonicalQueryString);
        return sb.toString();
    }

    private static void appendIfPresent(StringBuilder sb, String value) {
        if (value != null) {
            sb.append(value).append("\n");
        } else {
            sb.append("\n");
        }
    }

    private static String signString(String stringToSign) {
        try {
            Mac mac = Mac.getInstance(ALGORITHM_NAME);
            mac.init(new SecretKeySpec(ACCESS_KEY_SECRET.getBytes(StandardCharsets.UTF_8), ALGORITHM_NAME));
            byte[] signData = mac.doFinal(stringToSign.getBytes(StandardCharsets.UTF_8));
            return DatatypeConverter.printBase64Binary(signData);
        } catch (NoSuchAlgorithmException | InvalidKeyException ex) {
            throw new IllegalArgumentException(ex.toString());
        }
    }

    public static String md5Sum(byte[] buff) {
        try {
            MessageDigest md = MessageDigest.getInstance("MD5");
            byte[] md5Bytes = md.digest(buff);
            return DatatypeConverter.printBase64Binary(md5Bytes);
        } catch (NoSuchAlgorithmException ex) {
            throw new IllegalArgumentException(ex.toString());
        }
    }
}