NovaData API signature demo

App.java

package com.novacloud.data;

import org.apache.commons.codec.binary.Base64;

import javax.crypto.Mac;
import javax.crypto.spec.SecretKeySpec;
import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;

/**
 * NovaData API signature demo.
 * 代码参考 https://github.com/fit2cloud/qingcloud-api-java-wrapper/blob/master/src/main/java/com/fit2cloud/qingcloud/wsclient/QingCloudWSClient.java
 */
public class App {
    private static final String ENCODING = "UTF-8";

    private static String accessKeyId="NOVADATAACCESSKEYIDEXAMPLE";
    private static String secretKey="SECRETACCESSKEY";

    public static void main(String[] args) throws UnsupportedEncodingException {
        String method = "GET";
        Map<String, String> params = new HashMap<String, String>();
        params.put("access_key_id", accessKeyId);
        params.put("fields", "data.*");
        params.put("limit", "2");
        params.put("offset", "10");
        params.put("signature_version", "1");
        params.put("sort", "price:desc");
        String signature=computeSignature(method, params);
        System.out.println(signature);
        System.out.println(percentEncode(signature));
    }

    public static String computeSignature(String httpMethod,
                                          Map<String, String> parameters) {
        String[] sortedKeys = parameters.keySet().toArray(new String[]{});
        Arrays.sort(sortedKeys);
        final String SEPARATOR = "&";

        StringBuilder sbStringToSign = new StringBuilder();
        sbStringToSign.append(String.format("%s\n/v1/data/websites/1\n", httpMethod));

        String signature = "";
        try {
            int count = 0;

            for (String key : sortedKeys) {
                if (count != 0) {
                    sbStringToSign.append(SEPARATOR);
                }
                sbStringToSign.append(percentEncode(key)).append("=")
                        .append(percentEncode(parameters.get(key)));
                count++;
            }

            String strToSign = sbStringToSign.toString();
            signature = calculateSignature(secretKey, strToSign);
        } catch (UnsupportedEncodingException e) {
        } catch (Exception e) {
        }
        return signature;
    }

    private static String calculateSignature(String key, String stringToSign) {
        final String ALGORITHM = "HmacSHA256";
        byte[] signData = null;
        try {
            Mac mac = Mac.getInstance(ALGORITHM);
            mac.init(new SecretKeySpec(key.getBytes(ENCODING), ALGORITHM));
            signData = mac.doFinal(stringToSign.getBytes(ENCODING));
        } catch (InvalidKeyException e) {
        } catch (NoSuchAlgorithmException e) {
        } catch (UnsupportedEncodingException e) {
        } catch (IllegalStateException e) {
        }
        return new String(Base64.encodeBase64(signData));
    }

    private static String percentEncode(String value)
            throws UnsupportedEncodingException {
        return value != null ? URLEncoder.encode(value, ENCODING)
                .replace("+", "%20").replace("*", "%2A").replace("%7E", "~")
                : null;
    }

}