added disconnect functionality when stream is empty for 20 secs and some exception handling

Author: kisaga

examples/src/main/java/com/twitter/clientlib/HelloWorldStreaming.java

@@ -65,7 +65,7 @@ public static void main(String[] args) {
 
 class Responder implements TweetsStreamListener {
   @Override
-  public synchronized void actionOnTweetsStream(StreamingTweet streamingTweet) {
+  public synchronized void onTweetArrival(StreamingTweet streamingTweet) {
     if(streamingTweet == null) {
       System.err.println("Error: actionOnTweetsStream - streamingTweet is null ");
       return;

src/main/java/com/twitter/clientlib/api/TweetsApi.java

@@ -23,25 +23,16 @@
 package com.twitter.clientlib.api;
 
 import com.twitter.clientlib.ApiCallback;
-import com.twitter.clientlib.ApiClient;
-import com.twitter.clientlib.auth.*;
 import com.twitter.clientlib.ApiException;
 import com.twitter.clientlib.ApiResponse;
-import com.twitter.clientlib.Configuration;
 import com.twitter.clientlib.Pair;
-import com.twitter.clientlib.ProgressRequestBody;
-import com.twitter.clientlib.ProgressResponseBody;
 
-import com.github.scribejava.core.model.OAuth2AccessToken;
 import com.google.gson.reflect.TypeToken;
 
-import java.io.IOException;
-
 
 import com.twitter.clientlib.model.AddOrDeleteRulesRequest;
 import com.twitter.clientlib.model.AddOrDeleteRulesResponse;
 import com.twitter.clientlib.model.CreateTweetRequest;
-import com.twitter.clientlib.model.Error;
 import com.twitter.clientlib.model.FilteredStreamingTweet;
 import com.twitter.clientlib.model.GenericTweetsTimelineResponse;
 import com.twitter.clientlib.model.GetRulesResponse;
@@ -52,7 +43,7 @@
 import com.twitter.clientlib.model.MultiTweetLookupResponse;
 import com.twitter.clientlib.model.MultiUserLookupResponse;
 import java.time.OffsetDateTime;
-import com.twitter.clientlib.model.Problem;
+
 import com.twitter.clientlib.model.QuoteTweetLookupResponse;
 import com.twitter.clientlib.model.SingleTweetLookupResponse;
 import com.twitter.clientlib.model.StreamingTweet;
@@ -75,11 +66,8 @@
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
-import java.io.InputStream;
-import javax.ws.rs.core.GenericType;
 
 import okio.BufferedSource;
-import org.apache.commons.lang3.StringUtils;
 
 public class TweetsApi extends ApiCommon {
 

src/main/java/com/twitter/clientlib/exceptions/AuthenticationException.java

@@ -0,0 +1,12 @@
+package com.twitter.clientlib.exceptions;
+
+public class AuthenticationException extends RuntimeException {
+
+    public AuthenticationException(String message) {
+        super(message);
+    }
+
+    public AuthenticationException(String message, Throwable cause) {
+        super(message, cause);
+    }
+}

src/main/java/com/twitter/clientlib/exceptions/EmptyStreamTimeoutException.java

@@ -0,0 +1,7 @@
+package com.twitter.clientlib.exceptions;
+
+public class EmptyStreamTimeoutException extends RuntimeException {
+    public EmptyStreamTimeoutException(String message) {
+        super(message);
+    }
+}

src/main/java/com/twitter/clientlib/stream/TweetsStreamExecutor.java

@@ -23,6 +23,7 @@
 package com.twitter.clientlib.stream;
 
 
+import java.io.IOException;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.concurrent.BlockingQueue;
@@ -36,10 +37,14 @@
 import com.fasterxml.jackson.databind.JsonMappingException;
 import com.fasterxml.jackson.databind.ObjectMapper;
 
+import com.twitter.clientlib.exceptions.EmptyStreamTimeoutException;
 import com.twitter.clientlib.model.StreamingTweet;
 import okio.BufferedSource;
 
 public class TweetsStreamExecutor {
+
+  private static final long EMPTY_STREAM_TIMEOUT = 20000;
+  private static final int POLL_WAIT = 5;
   private volatile BlockingQueue<String> rawTweets;
   private volatile BlockingQueue<StreamingTweet> tweets;
   private volatile boolean isRunning = true;
@@ -90,9 +95,12 @@ public synchronized void shutdown() {
     shutDownServices();
     try {
       terminateServices();
+      stream.close();
     } catch (InterruptedException ie) {
       shutDownServices();
       Thread.currentThread().interrupt();
+    } catch (IOException e) {
+
     }
     System.out.println("TweetsStreamListenersExecutor is shutting down.");
   }
@@ -109,9 +117,9 @@ private void terminateServices() throws InterruptedException {
     terminateService(listenersService);
   }
   private void terminateService(ExecutorService executorService) throws InterruptedException {
-    if (!executorService.awaitTermination(3, TimeUnit.SECONDS)) {
+    if (!executorService.awaitTermination(1500, TimeUnit.MILLISECONDS)) {
       executorService.shutdownNow();
-      if (!executorService.awaitTermination(3, TimeUnit.SECONDS))
+      if (!executorService.awaitTermination(1500, TimeUnit.MILLISECONDS))
         System.err.println("Pool did not terminate");
     }
   }
@@ -126,19 +134,32 @@ public void run() {
     public void queueTweets() {
       String line = null;
       try {
+        boolean emptyResponse = false;
+        long firstEmptyResponseMillis = 0;
+        long lastEmptyReponseMillis;
         while (isRunning) {
           line = stream.readUtf8Line();
           if(line == null || line.isEmpty()) {
+            if(!emptyResponse) {
+              firstEmptyResponseMillis = System.currentTimeMillis();
+              emptyResponse = true;
+            } else {
+              lastEmptyReponseMillis = System.currentTimeMillis();
+              if(lastEmptyReponseMillis - firstEmptyResponseMillis > EMPTY_STREAM_TIMEOUT) {
+                throw new EmptyStreamTimeoutException(String.format("Stream was empty for %d seconds consecutively", EMPTY_STREAM_TIMEOUT));
+              } 
+            }
             continue;
           }
+          emptyResponse = false;
           try {
             rawTweets.put(line);
-          } catch (Exception interExcep) {
-            interExcep.printStackTrace();
+          } catch (Exception ignore) {
+
           }
         }
       } catch (Exception e) {
-        e.printStackTrace();
+        System.out.println("Something went wrong. Closing stream... " + e.getMessage());
         shutdown();
       }
     }
@@ -156,15 +177,14 @@ private DeserializeTweetsTask() {
     public void run() {
       while (isRunning) {
         try {
-          String rawTweet = rawTweets.take();
+          String rawTweet = rawTweets.poll(POLL_WAIT, TimeUnit.MILLISECONDS);
+          if (rawTweet == null) continue;
           StreamingTweet tweet = objectMapper.readValue(rawTweet, StreamingTweet.class);
           tweets.put(tweet);
         } catch (InterruptedException e) {
-          System.out.println("Fail 1");
-        } catch (JsonMappingException e) {
-          System.out.println("Fail 2");
+
         } catch (JsonProcessingException e) {
-          System.out.println("Fail 3");
+          System.out.println("debug log here");
         }
       }
     }
@@ -181,9 +201,10 @@ private void processTweets() {
 
         while (isRunning) {
           try {
-            streamingTweet = tweets.take();
+            streamingTweet = tweets.poll(POLL_WAIT, TimeUnit.MILLISECONDS);
+            if(streamingTweet == null) continue;
             for (TweetsStreamListener listener : listeners) {
-              listener.actionOnTweetsStream(streamingTweet);
+              listener.onTweetArrival(streamingTweet);
             }
             tweetsCount++;
             if(tweetsCount == tweetsLimit) {
@@ -194,7 +215,7 @@ private void processTweets() {
               shutdown();
             }
           } catch (InterruptedException e) {
-            System.out.println("processTweets: Fail 1");
+
           }
 
         }

src/main/java/com/twitter/clientlib/stream/TweetsStreamListener.java

@@ -25,5 +25,5 @@
 import com.twitter.clientlib.model.StreamingTweet;
 
 public interface TweetsStreamListener {
-  void actionOnTweetsStream(StreamingTweet streamingTweet);
+  void onTweetArrival(StreamingTweet streamingTweet);
 }

src/main/java/com/twitter/clientlib/stream/TwitterStream.java

@@ -4,10 +4,10 @@
 import com.twitter.clientlib.ApiException;
 import com.twitter.clientlib.TwitterCredentialsBearer;
 import com.twitter.clientlib.api.TweetsApi;
+import com.twitter.clientlib.exceptions.AuthenticationException;
 import com.twitter.clientlib.query.StreamQueryParameters;
 import okio.BufferedSource;
 
-import java.io.InputStream;
 import java.util.LinkedList;
 import java.util.List;
 
@@ -38,15 +38,14 @@ public void sampleStream(StreamQueryParameters streamParameters) {
             listeners.forEach(executor::addListener);
             executor.start();
         } catch (ApiException e) {
-            System.err.println("Status code: " + e.getCode());
-            System.err.println("Reason: " + e.getResponseBody());
-            System.err.println("Response headers: " + e.getResponseHeaders());
-            e.printStackTrace();
+            if(e.getCode() == 401) {
+                throw new AuthenticationException("Not authenticated. Please check the credentials", e);
+            }
         }
     }
 
     private void initBasePath() {
-        String basePath = "http://localhost:8080";
+        String basePath = System.getenv("TWITTER_API_BASE_PATH");
         apiClient.setBasePath(basePath != null ? basePath : "https://api.twitter.com");
     }