step-by-step-auth-token

SendbeeAuthToken.java

import java.math.BigInteger;
import java.nio.charset.StandardCharsets;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.crypto.Mac;
import javax.crypto.spec.SecretKeySpec;
import javax.xml.bind.DatatypeConverter;

/**
 *
 * @author kimathie
 */
public class SendbeeAuthToken {

    public static void main(String[] args) {

        /**
         * Assigned secret key
         */
        String secret_key = "zodux3ITAPW4cGsvn6rGbLEAgRNLphPJ7OF121nl";

        try {
            /**
             * Step 1: get current timestamp (in seconds)
             * Use the line below to generate current timestamp in seconds as a String
             * 
             * Long.toString(Instant.now().getEpochSecond());
             */
            String timestamp = "1586286575";

            /**
             * Step 2: encrypt the timestamp with your API secret key using HMAC
             * sha256 encrypt algorithm
             */
            String lowerHexit_UTF_8_Hash = SendbeeAuthToken.hmac256LowerHexit(secret_key, timestamp, StandardCharsets.UTF_8.name());
            System.out.println("Lower Hexit UTF_8 Hash: " + lowerHexit_UTF_8_Hash);

            /**
             * Step 3: concatenate timestamp and encrypted timestamp separated
             * by a . (dot)
             */
            String lowerHexit_UTF_8_Hash_Concatenate = timestamp + "." + lowerHexit_UTF_8_Hash;
            System.out.println("Lower Hexit UTF_8 Hash Concatenate: " + lowerHexit_UTF_8_Hash_Concatenate);

            /**
             * Step 4: translate concatenated string into base64
             */
            String lowerHexit_UTF_8_Hash_Concatenate_Token = DatatypeConverter.printBase64Binary(lowerHexit_UTF_8_Hash_Concatenate.getBytes(StandardCharsets.UTF_8));
            System.out.println("Lower Hexit UTF_8_Hash_Concatenate_Token: " + lowerHexit_UTF_8_Hash_Concatenate_Token);

        } catch (Exception ex) {
            Logger.getLogger(SendbeeAuthToken.class.getName()).log(Level.SEVERE, null, ex);
        }
    }

    /**
     *
     * @param key A secret cryptographic key
     * @param data The information to be encrypted
     * @param charsetName the encoding to be used
     * @return A String representation of the hash
     * @throws Exception
     */
    public static String hmac256LowerHexit(String key, String data, String charsetName) throws Exception {
        return toLowerHexit(hmac256Raw(key, data, charsetName));
    }

    /**
     * Encrypts the data into raw bytes using the encoding of choice
     */
    public static byte[] hmac256Raw(String key, String data, String charsetName) throws Exception {
        Mac hasher = Mac.getInstance("HmacSHA256");
        hasher.init(new SecretKeySpec(key.getBytes(charsetName), "HmacSHA256"));
        return hasher.doFinal(data.getBytes(charsetName));
    }

    /**
     * Returns the lower representation of the hexadecimal bits
     */
    private static String toLowerHexit(byte[] value) {
        String hexed = String.format("%040x", new BigInteger(1, value));
        return hexed;
    }
}