Merge pull request #47 from GetStream/feature/getUserSessionToken

Added getUserSessionToken()

Author: sirio7g

stream-core/src/main/java/io/getstream/client/model/feeds/BaseFeed.java

@@ -48,6 +48,11 @@ public String getReadOnlyToken() {
         return streamRepository.getReadOnlyToken(this);
     }
 
+    @Override
+    public String getUserSessionToken() {
+        return streamRepository.getUserSessionToken(this);
+    }
+
     @Override
     public void follow(String feedSlug, String userId) throws IOException, StreamClientException {
         String feedId = String.format("%s:%s", feedSlug, userId);

stream-core/src/main/java/io/getstream/client/model/feeds/Feed.java

@@ -39,6 +39,12 @@ public interface Feed {
      */
     String getReadOnlyToken();
 
+    /**
+     * Generate User Session JWT Token. UserId is taken from {@link Feed#getId()}.
+     * @return Token
+     */
+    String getUserSessionToken();
+
     /**
      * Follows the given target feed.
      *

stream-core/src/main/java/io/getstream/client/repo/StreamRepository.java

@@ -48,6 +48,8 @@ public interface StreamRepository {
      */
     String getReadOnlyToken(BaseFeed feed);
 
+    String getUserSessionToken(BaseFeed feed);
+
     /**
      * Follow a feed.
      *

stream-core/src/main/java/io/getstream/client/util/JwtAuthenticationUtil.java

@@ -1,11 +1,11 @@
 package io.getstream.client.util;
 
-import java.io.UnsupportedEncodingException;
-
 import com.auth0.jwt.JWT;
 import com.auth0.jwt.JWTCreator;
 import com.auth0.jwt.algorithms.Algorithm;
 
+import java.io.UnsupportedEncodingException;
+
 /**
  * Utility class to generate a JWT token.
  */
@@ -28,8 +28,41 @@ public class JwtAuthenticationUtil {
     public static String generateToken(final String secretKey, final String action, final String resource, final String feedId, final String userId) {
         JWTCreator.Builder jwtBuilder = JWT.create();
 
-        jwtBuilder = jwtBuilder.withClaim("action", action);
-        jwtBuilder = jwtBuilder.withClaim("resource", resource);
+        if (null != action) {
+            jwtBuilder = jwtBuilder.withClaim("action", action);
+        }
+
+        if (null != resource) {
+            jwtBuilder = jwtBuilder.withClaim("resource", resource);
+        }
+
+        if (null != feedId) {
+            jwtBuilder = jwtBuilder.withClaim("feed_id", feedId);
+        }
+
+        if (null != userId) {
+            jwtBuilder = jwtBuilder.withClaim("user_id", userId);
+        }
+
+        try {
+            Algorithm algorithm = Algorithm.HMAC256(secretKey);
+
+            return jwtBuilder.sign(algorithm);
+        } catch (UnsupportedEncodingException exc) {
+            throw new IllegalStateException("Fatal error: JWT Algorithm unsupported.");
+        }
+    }
+
+    /**
+     * Generate JWT token.
+     * @param secretKey API Secret
+     * @param feedId FeedId (if null it will not be added to the payload)
+     * @param userId UserId (if null it will not be added to the payload)
+     * @return Token string
+     */
+    public static String generateToken(final String secretKey, final String feedId, final String userId) {
+        JWTCreator.Builder jwtBuilder = JWT.create();
+
         if (null != feedId) {
             jwtBuilder = jwtBuilder.withClaim("feed_id", feedId);
         }

stream-repo-apache/src/main/java/io/getstream/client/apache/repo/StreamRepositoryImpl.java

@@ -83,6 +83,11 @@ public String getReadOnlyToken(BaseFeed feed) {
 		return JwtAuthenticationUtil.generateToken(secretKey, "read", "*", feed.getFeedSlug().concat(feed.getUserId()), null);
 	}
 
+	@Override
+	public String getUserSessionToken(BaseFeed feed) {
+		return JwtAuthenticationUtil.generateToken(secretKey, null, feed.getUserId());
+	}
+
 	@Override
 	public void follow(BaseFeed feed, String targetFeedId, int activityCopyLimit) throws StreamClientException, IOException {
 		HttpPost request = new HttpPost(UriBuilder.fromEndpoint(baseEndpoint)

stream-repo-apache/src/test/java/io/getstream/client/apache/IntegrationTest.java

@@ -78,6 +78,15 @@ public void shouldGetReadOnlyToken() throws IOException, StreamClientException,
         assertThat(map.get("resource").asString(), is(ALL));
     }
 
+    @Test
+    public void shouldGetUserSessionToken() throws StreamClientException {
+        StreamClient streamClient = new StreamClientImpl(CLIENT_CONFIGURATION, API_KEY, API_SECRET);
+        Feed feed = streamClient.newFeed("feedslug", "aUserId");
+
+        Map<String, Claim> map = verifyToken(feed.getUserSessionToken());
+        assertThat(map.get("user_id").asString(), is("aUserId"));
+    }
+
     @Test
     public void shouldGetFollowers() throws IOException, StreamClientException {
         StreamClient streamClient = new StreamClientImpl(CLIENT_CONFIGURATION, API_KEY,

stream-repo-okhttp/src/main/java/io/getstream/client/okhttp/repo/StreamRepositoryImpl.java

@@ -86,6 +86,11 @@ public String getToken(BaseFeed feed) {
 		return StreamRepoUtils.createFeedToken(feed, secretKey);
 	}
 
+	@Override
+	public String getUserSessionToken(BaseFeed feed) {
+		return JwtAuthenticationUtil.generateToken(secretKey, null, feed.getUserId());
+	}
+
 	@Override
 	public void follow(BaseFeed feed, String targetFeedId, int activityCopyLimit) throws StreamClientException, IOException {
 		Request.Builder requestBuilder = new Request.Builder().url(UriBuilder.fromEndpoint(baseEndpoint)

stream-repo-okhttp/src/test/java/io/getstream/client/okhttp/IntegrationTest.java

@@ -68,6 +68,15 @@ public void shouldGetReadOnlyToken() throws StreamClientException {
         assertThat(map.get("resource").asString(), is(ALL));
     }
 
+    @Test
+    public void shouldGetUserSessionToken() throws StreamClientException {
+        StreamClient streamClient = new StreamClientImpl(CLIENT_CONFIGURATION, API_KEY, API_SECRET);
+        Feed feed = streamClient.newFeed("feedslug", "aUserId");
+
+        Map<String, Claim> map = verifyToken(feed.getUserSessionToken());
+        assertThat(map.get("user_id").asString(), is("aUserId"));
+    }
+
     @Test
     public void shouldGetFollowers() throws IOException, StreamClientException {
         StreamClient streamClient = new StreamClientImpl(CLIENT_CONFIGURATION, API_KEY,