Fix failing test. (apache#11186)

The hard coded token has expired causing the test to fail.

Instead of hardcoding the token, we can generate the token dynamically and
avoid this problem in future

Co-authored-by: Surinder Singh <surinders@splunk.com>

pulsar-broker/src/test/java/org/apache/pulsar/client/api/TokenAuthenticatedProducerConsumerTest.java

@@ -21,7 +21,16 @@
 import static org.mockito.Mockito.spy;
 
 import com.google.common.collect.Sets;
+import io.jsonwebtoken.Jwts;
+import io.jsonwebtoken.SignatureAlgorithm;
 import java.net.URI;
+import java.security.KeyPair;
+import java.security.KeyPairGenerator;
+import java.security.NoSuchAlgorithmException;
+import java.security.PrivateKey;
+import java.time.Duration;
+import java.util.Base64;
+import java.util.Date;
 import java.util.HashSet;
 import java.util.Properties;
 import java.util.Set;
@@ -47,10 +56,29 @@
 public class TokenAuthenticatedProducerConsumerTest extends ProducerConsumerBase {
     private static final Logger log = LoggerFactory.getLogger(TokenAuthenticatedProducerConsumerTest.class);
 
-    // pre-create a public/private_key pair.  Public key used for broker to verify client passed in token
-    private final String TOKEN_PUBLIC_KEY = "data:;base64,MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAhHKgdY6arG7eE75bUPtznN5WjMu0sxLq7pI5Aaiw2Ijerbz33iO/Fdd2yJVuAZNDZPD/AVSaeliEh/BP+s2rN8KNuiywD+SlL1NGf2JDS5BvGT4Q8eHfDDRd/iY5zkK58wYwlke6C8fKCx10MTH9iYAJpzaaxs+Tu1RaatK+691aYSiMkYIfgbqAKmSCpK+48al/PkmENfuhzaTBPhCnEblhNvUhS5MjzBcAcGzecpEuVSxUzDtm8rU8DEQR6kkdXS1QnGHVNis/vgk8QzctkJKbtgDIaGzNUmDvTCyPZ8WLWSWJWb1oPxRZwpfXVP69ijU0Rme4/YkuHt6IEw6ANQIDAQAB";
-    // admin token created based on private_key.
-    private final String ADMIN_TOKEN = "eyJhbGciOiJSUzI1NiJ9.eyJzdWIiOiJhZG1pbiIsImV4cCI6MTYyNTEzNjQyMn0.DAfbUPZwQURgGvor4scO0NoqoyHkCulKZkhP7kksCWFvgx6B22iKuXGX42EFlFSRMWYYgIJXV7UZATCLCjJpn_ijrO6AWBmooib3f94OPoLDdkF3qXnqaLnvJtl8_sCoLCSghR_O3hQFgQW2GRjMDdfJgl2_HXCWuzedtI5cQJdbpfU0NU10nzo7RtrpCmUdgQYQEHegYOawLqQVvr53ZGjrZilBXY9HHz1mSlnwZGNGVNNdvRthBuGtXtfKgtfSDF5jLqABvK8TUpdNJybibeiOspdzuY19-wVt4eVXzNAGsP4V4Zs91MgIUYV5lWKnBUuVWalppkMWhRF4Jf-KWQ";
+    private final String ADMIN_TOKEN;
+    private final String TOKEN_PUBLIC_KEY;
+
+    TokenAuthenticatedProducerConsumerTest() throws NoSuchAlgorithmException {
+        KeyPairGenerator kpg = KeyPairGenerator.getInstance("RSA");
+        KeyPair kp = kpg.generateKeyPair();
+
+        byte[] encodedPublicKey = kp.getPublic().getEncoded();
+        TOKEN_PUBLIC_KEY = "data:;base64," + Base64.getEncoder().encodeToString(encodedPublicKey);
+        ADMIN_TOKEN = generateToken(kp);
+    }
+
+    private String generateToken(KeyPair kp) {
+        PrivateKey pkey = kp.getPrivate();
+        long expMillis = System.currentTimeMillis() + Duration.ofHours(1).toMillis();
+        Date exp = new Date(expMillis);
+
+        return Jwts.builder()
+            .setSubject("admin")
+            .setExpiration(exp)
+            .signWith(pkey, SignatureAlgorithm.forSigningKey(pkey))
+            .compact();
+    }
 
     @BeforeMethod
     @Override