feat(faye): add websocket client

.github/workflows/ci.yml

@@ -2,7 +2,7 @@ name: build
 
 on: [pull_request]
 
-concurrency: 
+concurrency:
   group: ${{ github.workflow }}-${{ github.head_ref }}
   cancel-in-progress: true
 
@@ -31,6 +31,7 @@ jobs:
         env:
           STREAM_KEY: ${{ secrets.STREAM_KEY }}
           STREAM_SECRET: ${{ secrets.STREAM_SECRET }}
+          STREAM_APP_ID: ${{ secrets.STREAM_APP_ID }}
         run: |
           ./gradlew spotlessCheck --no-daemon
           ./gradlew test --no-daemon

.github/workflows/initiate_release.yml

@@ -21,7 +21,7 @@ jobs:
           VERSION: ${{ github.event.inputs.version }}
         run: |
           npx --yes standard-version@9.3.2 --release-as "$VERSION" --skip.tag --skip.commit --tag-prefix=v
-          git config --global user.name 'github-actions' 
+          git config --global user.name 'github-actions'
           git config --global user.email 'release@getstream.io'
           git checkout -q -b "release-$VERSION"
           git commit -am "chore(release): $VERSION"

.github/workflows/release.yml

@@ -15,7 +15,7 @@ jobs:
       - uses: actions/checkout@v3
         with:
           fetch-depth: 0
-  
+
       - uses: actions/github-script@v5
         with:
           script: |
@@ -34,6 +34,7 @@ jobs:
         env:
           STREAM_KEY: ${{ secrets.STREAM_KEY }}
           STREAM_SECRET: ${{ secrets.STREAM_SECRET }}
+          STREAM_APP_ID: ${{ secrets.STREAM_APP_ID }}
           GPG_KEY_CONTENTS: ${{ secrets.GPG_KEY_CONTENTS }}
           OSSRH_USERNAME: ${{ secrets.OSSRH_USERNAME }}
           OSSRH_PASSWORD: ${{ secrets.OSSRH_PASSWORD }}

src/main/java/io/getstream/cloud/CloudAggregatedFeed.java

@@ -20,6 +20,10 @@ public class CloudAggregatedFeed extends CloudFeed {
     super(client, id);
   }
 
+  CloudAggregatedFeed(CloudClient client, FeedID id, FeedSubscriber subscriber) {
+    super(client, id, subscriber);
+  }
+
   public CompletableFuture<? extends List<? extends Group<Activity>>> getActivities()
       throws StreamException {
     return getActivities(

src/main/java/io/getstream/cloud/CloudClient.java

@@ -6,6 +6,10 @@
 import io.getstream.core.Region;
 import io.getstream.core.Stream;
 import io.getstream.core.exceptions.StreamException;
+import io.getstream.core.faye.DefaultMessageTransformer;
+import io.getstream.core.faye.Message;
+import io.getstream.core.faye.client.FayeClient;
+import io.getstream.core.faye.subscription.ChannelSubscription;
 import io.getstream.core.http.HTTPClient;
 import io.getstream.core.http.OKHTTPClientAdapter;
 import io.getstream.core.http.Response;
@@ -14,20 +18,38 @@
 import io.getstream.core.models.Data;
 import io.getstream.core.models.FeedID;
 import io.getstream.core.models.OGData;
+import io.getstream.core.models.RealtimeMessage;
 import io.getstream.core.options.RequestOption;
+import io.getstream.core.utils.Serialization;
 import java.net.MalformedURLException;
 import java.net.URL;
+import java.util.HashMap;
+import java.util.Map;
 import java8.util.concurrent.CompletableFuture;
 
 public final class CloudClient {
+  private final String apiKey;
   private final Token token;
+  private final String appID;
   private final String userID;
   private final Stream stream;
-
-  private CloudClient(String key, Token token, String userID, URL baseURL, HTTPClient httpClient) {
+  private final FayeClient faye;
+
+  private CloudClient(
+      String key,
+      Token token,
+      String userID,
+      String appID,
+      URL baseURL,
+      HTTPClient httpClient,
+      URL fayeURL) {
+    this.apiKey = key;
     this.token = token;
+    this.appID = appID;
     this.userID = userID;
     this.stream = new Stream(key, baseURL, httpClient);
+    this.faye = new FayeClient(fayeURL);
+    this.faye.setMessageTransformer(new FayeMessageTransformer());
   }
 
   public static Builder builder(String apiKey, String token, String userID) {
@@ -38,22 +60,25 @@ public static Builder builder(String apiKey, Token token, String userID) {
     return new Builder(apiKey, token, userID);
   }
 
-  public CompletableFuture<OGData> openGraph(URL url) throws StreamException {
-    return stream.openGraph(token, url);
+  public static Builder builder(String apiKey, Token token, String userID, String appID) {
+    return new Builder(apiKey, token, userID, appID);
   }
 
   public static final class Builder {
     private static final String DEFAULT_HOST = "stream-io-api.com";
+    private static final String DEFAULT_FAYE_URL = "https://faye-us-east.stream-io-api.com/faye";
 
     private final String apiKey;
     private final Token token;
     private final String userID;
+    private final String appID;
     private HTTPClient httpClient;
 
     private String scheme = "https";
     private String region = Region.US_EAST.toString();
     private String host = DEFAULT_HOST;
     private int port = 443;
+    private String fayeURL = DEFAULT_FAYE_URL;
 
     public Builder(String apiKey, Token token, String userID) {
       checkNotNull(apiKey, "API key can't be null");
@@ -64,6 +89,19 @@ public Builder(String apiKey, Token token, String userID) {
       this.apiKey = apiKey;
       this.token = token;
       this.userID = userID;
+      this.appID = null;
+    }
+
+    public Builder(String apiKey, Token token, String userID, String appID) {
+      checkNotNull(apiKey, "API key can't be null");
+      checkNotNull(token, "Token can't be null");
+      checkNotNull(userID, "User ID can't be null");
+      checkArgument(!apiKey.isEmpty(), "API key can't be empty");
+      checkArgument(!userID.isEmpty(), "User ID can't be empty");
+      this.apiKey = apiKey;
+      this.token = token;
+      this.userID = userID;
+      this.appID = appID;
     }
 
     public Builder httpClient(HTTPClient httpClient) {
@@ -105,6 +143,13 @@ public Builder region(String region) {
       return this;
     }
 
+    public Builder fayeURL(String fayeURL) {
+      checkNotNull(fayeURL, "FayeUrl can't be null");
+      checkArgument(!fayeURL.isEmpty(), "FayeUrl can't be empty");
+      this.fayeURL = fayeURL;
+      return this;
+    }
+
     private String buildHost() {
       final StringBuilder sb = new StringBuilder();
       if (host.equals(DEFAULT_HOST)) {
@@ -118,15 +163,97 @@ public CloudClient build() throws MalformedURLException {
       if (httpClient == null) {
         httpClient = new OKHTTPClientAdapter();
       }
+
       return new CloudClient(
-          apiKey, token, userID, new URL(scheme, buildHost(), port, ""), httpClient);
+          apiKey,
+          token,
+          userID,
+          appID,
+          new URL(scheme, buildHost(), port, ""),
+          httpClient,
+          new URL(DEFAULT_FAYE_URL));
+    }
+  }
+
+  private static class FeedSubscription {
+    private String token;
+    private String userId;
+    private ChannelSubscription channelSubscription;
+
+    private FeedSubscription(String token, String userId) {
+      this.token = token;
+      this.userId = userId;
+    }
+
+    private FeedSubscription(String token, String userId, ChannelSubscription subscription) {
+      this.token = token;
+      this.userId = userId;
+      this.channelSubscription = subscription;
+    }
+  }
+
+  private final Map<String, FeedSubscription> feedSubscriptions = new HashMap<>();
+
+  private class FayeMessageTransformer extends DefaultMessageTransformer {
+    @Override
+    public Message transformRequest(Message message) {
+      final String subscription = message.getSubscription();
+      if (feedSubscriptions.containsKey(subscription)) {
+        final FeedSubscription feedSubscription = feedSubscriptions.get(subscription);
+        final Map<String, Object> ext = new HashMap<>();
+        ext.put("user_id", feedSubscription.userId);
+        ext.put("api_key", apiKey);
+        ext.put("signature", feedSubscription.token);
+        message.setExt(ext);
+      }
+      return message;
     }
   }
 
   public <T> T getHTTPClientImplementation() {
     return stream.getHTTPClientImplementation();
   }
 
+  public CompletableFuture<OGData> openGraph(URL url) throws StreamException {
+    return stream.openGraph(token, url);
+  }
+
+  private CompletableFuture<ChannelSubscription> feedSubscriber(
+      FeedID feedId, RealtimeMessageCallback messageCallback) {
+    final CompletableFuture<ChannelSubscription> subscriberCompletion = new CompletableFuture<>();
+    try {
+      checkNotNull(appID, "Missing app id, which is needed in order to subscribe feed");
+      final String claim = feedId.getClaim();
+      final String notificationChannel = "site" + "-" + appID + "-" + "feed" + "-" + claim;
+      final FeedSubscription subscription =
+          new FeedSubscription(token.toString(), notificationChannel);
+      feedSubscriptions.put("/" + notificationChannel, subscription);
+
+      final ChannelSubscription channelSubscription =
+          faye.subscribe(
+                  "/" + notificationChannel,
+                  data -> {
+                    try {
+                      final byte[] payload = Serialization.toJSON(data);
+                      final RealtimeMessage message =
+                          Serialization.fromJSON(new String(payload), RealtimeMessage.class);
+                      messageCallback.onMessage(message);
+                    } catch (Exception e) {
+                      e.printStackTrace();
+                    }
+                  },
+                  () -> feedSubscriptions.remove("/" + notificationChannel))
+              .get();
+
+      subscription.channelSubscription = channelSubscription;
+      feedSubscriptions.put("/" + notificationChannel, subscription);
+      subscriberCompletion.complete(channelSubscription);
+    } catch (Exception e) {
+      subscriberCompletion.completeExceptionally(e);
+    }
+    return subscriberCompletion;
+  }
+
   // TODO: add personalized feed versions
   public CloudFlatFeed flatFeed(String slug) {
     return flatFeed(slug, userID);
@@ -141,7 +268,7 @@ public CloudFlatFeed flatFeed(String slug, String userID) {
   }
 
   public CloudFlatFeed flatFeed(FeedID id) {
-    return new CloudFlatFeed(this, id);
+    return new CloudFlatFeed(this, id, this::feedSubscriber);
   }
 
   public CloudAggregatedFeed aggregatedFeed(String slug) {
@@ -157,7 +284,7 @@ public CloudAggregatedFeed aggregatedFeed(String slug, String userID) {
   }
 
   public CloudAggregatedFeed aggregatedFeed(FeedID id) {
-    return new CloudAggregatedFeed(this, id);
+    return new CloudAggregatedFeed(this, id, this::feedSubscriber);
   }
 
   public CloudNotificationFeed notificationFeed(String slug) {
@@ -173,7 +300,7 @@ public CloudNotificationFeed notificationFeed(String slug, String userID) {
   }
 
   public CloudNotificationFeed notificationFeed(FeedID id) {
-    return new CloudNotificationFeed(this, id);
+    return new CloudNotificationFeed(this, id, this::feedSubscriber);
   }
 
   public CloudUser user(String userID) {

src/main/java/io/getstream/cloud/CloudFeed.java

@@ -6,6 +6,7 @@
 
 import com.google.common.collect.Iterables;
 import io.getstream.core.exceptions.StreamException;
+import io.getstream.core.faye.subscription.ChannelSubscription;
 import io.getstream.core.http.Response;
 import io.getstream.core.models.Activity;
 import io.getstream.core.models.FeedID;
@@ -26,19 +27,36 @@
 public class CloudFeed {
   private final CloudClient client;
   private final FeedID id;
+  private final FeedSubscriber subscriber;
 
   CloudFeed(CloudClient client, FeedID id) {
     checkNotNull(client, "Can't create feed w/o a client");
     checkNotNull(id, "Can't create feed w/o an ID");
 
     this.client = client;
     this.id = id;
+    this.subscriber = null;
+  }
+
+  CloudFeed(CloudClient client, FeedID id, FeedSubscriber subscriber) {
+    checkNotNull(client, "Can't create feed w/o a client");
+    checkNotNull(id, "Can't create feed w/o an ID");
+
+    this.client = client;
+    this.id = id;
+    this.subscriber = subscriber;
   }
 
   protected final CloudClient getClient() {
     return client;
   }
 
+  public final CompletableFuture<ChannelSubscription> subscribe(
+      RealtimeMessageCallback messageCallback) {
+    checkNotNull(subscriber, "A subscriber must be provided in order to start listening to a feed");
+    return subscriber.subscribe(id, messageCallback);
+  }
+
   public final FeedID getID() {
     return id;
   }

src/main/java/io/getstream/cloud/CloudFlatFeed.java

@@ -19,6 +19,10 @@ public final class CloudFlatFeed extends CloudFeed {
     super(client, id);
   }
 
+  CloudFlatFeed(CloudClient client, FeedID id, FeedSubscriber subscriber) {
+    super(client, id, subscriber);
+  }
+
   public CompletableFuture<List<Activity>> getActivities() throws StreamException {
     return getActivities(
         DefaultOptions.DEFAULT_LIMIT,

src/main/java/io/getstream/cloud/CloudNotificationFeed.java

@@ -17,6 +17,10 @@ public final class CloudNotificationFeed extends CloudFeed {
     super(client, id);
   }
 
+  CloudNotificationFeed(CloudClient client, FeedID id, FeedSubscriber subscriber) {
+    super(client, id, subscriber);
+  }
+
   public CompletableFuture<PaginatedNotificationGroup<Activity>> getActivities()
       throws StreamException {
     return getActivities(

src/main/java/io/getstream/cloud/FeedSubscriber.java

@@ -0,0 +1,10 @@
+package io.getstream.cloud;
+
+import io.getstream.core.faye.subscription.ChannelSubscription;
+import io.getstream.core.models.FeedID;
+import java8.util.concurrent.CompletableFuture;
+
+public interface FeedSubscriber {
+  CompletableFuture<ChannelSubscription> subscribe(
+      FeedID feedID, RealtimeMessageCallback messageCallback);
+}

src/main/java/io/getstream/cloud/RealtimeMessageCallback.java

@@ -0,0 +1,7 @@
+package io.getstream.cloud;
+
+import io.getstream.core.models.RealtimeMessage;
+
+public interface RealtimeMessageCallback {
+  void onMessage(RealtimeMessage message);
+}