feat(sequentially): send events to the server sequentially.

Author: Enuviel

AndroidSDK/src/com/leanplum/Leanplum.java

@@ -573,7 +573,7 @@ public void noPendingDownloads() {
       });
 
       // Reduce latency by running the rest of the start call in a background thread.
-      Util.executeAsyncTask(new AsyncTask<Void, Void, Void>() {
+      Util.executeAsyncTask(true, new AsyncTask<Void, Void, Void>() {
         @Override
         protected Void doInBackground(Void... params) {
           try {
@@ -924,7 +924,7 @@ static void pause() {
     }
     LeanplumInternal.setIsPaused(true);
 
-    if (LeanplumInternal.isPaused()) {
+    if (LeanplumInternal.issuedStart()) {
       pauseInternal();
     } else {
       LeanplumInternal.addStartIssuedHandler(new Runnable() {

AndroidSDK/src/com/leanplum/internal/Constants.java

@@ -70,6 +70,7 @@ public static boolean isNoop() {
 
   public static class Defaults {
     public static final String COUNT_KEY = "__leanplum_unsynced";
+    public static final String START_COUNT_KEY = "__leanplum_unsynced_start";
     public static final String ITEM_KEY = "__leanplum_unsynced_%d";
     public static final String VARIABLES_KEY = "__leanplum_variables";
     public static final String ATTRIBUTES_KEY = "__leanplum_attributes";

AndroidSDK/src/com/leanplum/internal/FileManager.java

@@ -365,7 +365,7 @@ public static void enableResourceSyncing(final List<String> patternsToInclude,
       final List<Pattern> compiledExcludePatterns = compilePatterns(patternsToExclude);
 
       if (isAsync) {
-        Util.executeAsyncTask(new AsyncTask<Void, Void, Void>() {
+        Util.executeAsyncTask(false, new AsyncTask<Void, Void, Void>() {
           @Override
           protected Void doInBackground(Void... params) {
             try {

AndroidSDK/src/com/leanplum/internal/LeanplumInternal.java

@@ -384,7 +384,7 @@ public static void setUserLocationAttribute(final Location location,
       @Override
       public void onResponse(final boolean success) {
         // Geocoder query must be executed on background thread.
-        Util.executeAsyncTask(new AsyncTask<Void, Void, Void>() {
+        Util.executeAsyncTask(false, new AsyncTask<Void, Void, Void>() {
           @Override
           protected Void doInBackground(Void... voids) {
             if (!success) {

AndroidSDK/src/com/leanplum/internal/Request.java

@@ -55,6 +55,7 @@ public class Request {
   private static final long DEVELOPMENT_MIN_DELAY_MS = 100;
   private static final long DEVELOPMENT_MAX_DELAY_MS = 5000;
   private static final long PRODUCTION_DELAY = 60000;
+  private static final int MAX_ACTIONS_PER_API_CALL = 10000;
   private static final String LEANPLUM = "__leanplum__";
 
   private static String appId;
@@ -286,7 +287,7 @@ private void triggerErrorCallback(Exception e) {
   }
 
   @SuppressWarnings("BooleanMethodIsAlwaysInverted")
-  private boolean attachApiKeys(Map<String, Object> dict) {
+  private static boolean attachApiKeys(Map<String, Object> dict) {
     if (appId == null || accessKey == null) {
       Log.e("API keys are not set. Please use Leanplum.setAppIdForDevelopmentMode or "
           + "Leanplum.setAppIdForProductionMode.");
@@ -378,23 +379,24 @@ private void sendNow() {
 
     this.sendEventually();
 
-    final List<Map<String, Object>> requestsToSend = popUnsentRequests();
-    if (requestsToSend.isEmpty()) {
-      return;
-    }
-
-    final Map<String, Object> multiRequestArgs = new HashMap<>();
-    multiRequestArgs.put(Constants.Params.DATA, jsonEncodeUnsentRequests(requestsToSend));
-    multiRequestArgs.put(Constants.Params.SDK_VERSION, Constants.LEANPLUM_VERSION);
-    multiRequestArgs.put(Constants.Params.ACTION, Constants.Methods.MULTI);
-    multiRequestArgs.put(Constants.Params.TIME, Double.toString(new Date().getTime() / 1000.0));
-    if (!this.attachApiKeys(multiRequestArgs)) {
-      return;
-    }
-
-    Util.executeAsyncTask(new AsyncTask<Void, Void, Void>() {
+    Util.executeAsyncTask(true, new AsyncTask<Void, Void, Void>() {
       @Override
       protected Void doInBackground(Void... params) {
+        final List<Map<String, Object>> requestsToSend = getUnsentRequests();
+        if (requestsToSend.isEmpty()) {
+          return null;
+        }
+
+        final Map<String, Object> multiRequestArgs = new HashMap<>();
+        multiRequestArgs.put(Constants.Params.DATA, jsonEncodeUnsentRequests(requestsToSend));
+        multiRequestArgs.put(Constants.Params.SDK_VERSION, Constants.LEANPLUM_VERSION);
+        multiRequestArgs.put(Constants.Params.ACTION, Constants.Methods.MULTI);
+        multiRequestArgs.put(Constants.Params.TIME, Double.toString(new Date().getTime() / 1000.0));
+        if (!Request.attachApiKeys(multiRequestArgs)) {
+          return null;
+        }
+        saveUnsentRequest(requestsToSend);
+
         JSONObject result = null;
         HttpURLConnection op = null;
         try {
@@ -411,11 +413,10 @@ protected Void doInBackground(Void... params) {
             int statusCode = op.getResponseCode();
 
             Exception errorException = null;
-            if (statusCode >= 400) {
+            if (statusCode == 200) {
+              deleteSentRequests(requestsToSend.size());
+            } else if (statusCode >= 400) {
               errorException = new Exception("HTTP error " + statusCode);
-              if (statusCode == 408 || (statusCode >= 500 && statusCode <= 599)) {
-                pushUnsentRequests(requestsToSend);
-              }
             } else {
               if (result != null) {
                 int numResponses = Request.numResponses(result);
@@ -433,7 +434,6 @@ protected Void doInBackground(Void... params) {
                 Log.getStackTraceString(e));
             parseResponseJson(null, requestsToSend, e);
           } catch (Exception e) {
-            pushUnsentRequests(requestsToSend);
             Log.e("Unable to send request: " + e.toString() + "\n" +
                 Log.getStackTraceString(e));
             parseResponseJson(result, requestsToSend, e);
@@ -461,6 +461,64 @@ public void sendEventually() {
     }
   }
 
+  private static void deleteSentRequests(int requestSize) {
+    if (requestSize == 0) {
+      return;
+    }
+
+    synchronized (lock) {
+      Context context = Leanplum.getContext();
+      SharedPreferences preferences = context.getSharedPreferences(
+          LEANPLUM, Context.MODE_PRIVATE);
+      SharedPreferences.Editor editor = preferences.edit();
+      int start = preferences.getInt(Constants.Defaults.START_COUNT_KEY, 0);
+      for (int i = start; i < start + requestSize; i++) {
+        editor.remove(String.format(Locale.US, Constants.Defaults.ITEM_KEY, i));
+      }
+      editor.putInt(Constants.Defaults.START_COUNT_KEY, start + requestSize);
+      try {
+        editor.apply();
+      } catch (NoSuchMethodError e) {
+        editor.commit();
+      }
+    }
+  }
+
+  private static void updateRequest(int requestNumber, Map<String, Object> args) {
+    synchronized (lock) {
+      Context context = Leanplum.getContext();
+      SharedPreferences preferences = context.getSharedPreferences(
+          LEANPLUM, Context.MODE_PRIVATE);
+      SharedPreferences.Editor editor = preferences.edit();
+      int start = preferences.getInt(Constants.Defaults.START_COUNT_KEY, 0);
+      editor.putString(String.format(Locale.US, Constants.Defaults.ITEM_KEY, start + requestNumber),
+          JsonConverter.toJson(args));
+      try {
+        editor.apply();
+      } catch (NoSuchMethodError e) {
+        editor.commit();
+      }
+    }
+  }
+
+  private static void saveUnsentRequest(List<Map<String, Object>> requestData) {
+    if (requestData == null || requestData.isEmpty()) {
+      return;
+    }
+    for (int i = 0; i < requestData.size(); i++) {
+      Map<String, Object> args = requestData.get(i);
+      Object retryCountString = args.get("retryCount");
+      int retryCount;
+      if (retryCountString != null) {
+        retryCount = Integer.parseInt(retryCountString.toString()) + 1;
+      } else {
+        retryCount = 1;
+      }
+      args.put("retryCount", Integer.toString(retryCount));
+      updateRequest(i, args);
+    }
+  }
+
   static List<Map<String, Object>> popUnsentRequests() {
     return getUnsentRequests(true);
   }
@@ -474,7 +532,6 @@ private static List<Map<String, Object>> getUnsentRequests(boolean remove) {
 
     synchronized (lock) {
       lastSendTimeMs = System.currentTimeMillis();
-
       Context context = Leanplum.getContext();
       SharedPreferences preferences = context.getSharedPreferences(
           LEANPLUM, Context.MODE_PRIVATE);
@@ -484,11 +541,11 @@ private static List<Map<String, Object>> getUnsentRequests(boolean remove) {
       if (count == 0) {
         return new ArrayList<>();
       }
-      if (remove) {
-        editor.remove(Constants.Defaults.COUNT_KEY);
+      int start = preferences.getInt(Constants.Defaults.START_COUNT_KEY, 0);
+      if (count - start > MAX_ACTIONS_PER_API_CALL) {
+        count = MAX_ACTIONS_PER_API_CALL;
       }
-
-      for (int i = 0; i < count; i++) {
+      for (int i = start; i < count; i++) {
         String itemKey = String.format(Locale.US, Constants.Defaults.ITEM_KEY, i);
         Map<String, Object> requestArgs;
         try {
@@ -502,15 +559,16 @@ private static List<Map<String, Object>> getUnsentRequests(boolean remove) {
           editor.remove(itemKey);
         }
       }
-      if (remove) {
+      if (remove || count == start) {
+        editor.remove(Constants.Defaults.COUNT_KEY);
+        editor.remove(Constants.Defaults.START_COUNT_KEY);
         try {
           editor.apply();
         } catch (NoSuchMethodError e) {
           editor.commit();
         }
       }
     }
-
     requestData = removeIrrelevantBackgroundStartRequests(requestData);
     return requestData;
   }
@@ -560,22 +618,6 @@ private static String jsonEncodeUnsentRequests(List<Map<String, Object>> request
     return JsonConverter.toJson(data);
   }
 
-  private static void pushUnsentRequests(List<Map<String, Object>> requestData) {
-    if (requestData == null) {
-      return;
-    }
-    for (Map<String, Object> args : requestData) {
-      Object retryCountString = args.get("retryCount");
-      int retryCount;
-      if (retryCountString != null) {
-        retryCount = Integer.parseInt(retryCountString.toString()) + 1;
-      } else {
-        retryCount = 1;
-      }
-      args.put("retryCount", Integer.toString(retryCount));
-      saveRequestForLater(args);
-    }
-  }
 
   private static String getSizeAsString(int bytes) {
     if (bytes < (1 << 10)) {
@@ -650,7 +692,7 @@ public void sendFilesNow(final List<String> filenames, final List<InputStream> s
     printUploadProgress();
 
     // Now upload the files
-    Util.executeAsyncTask(new AsyncTask<Void, Void, Void>() {
+    Util.executeAsyncTask(false, new AsyncTask<Void, Void, Void>() {
       @Override
       protected Void doInBackground(Void... params) {
         synchronized (uploadFileLock) {  // Don't overload app and server with many upload tasks
@@ -734,7 +776,7 @@ void downloadFile(final String path, final String url) {
       return;
     }
 
-    Util.executeAsyncTask(new AsyncTask<Void, Void, Void>() {
+    Util.executeAsyncTask(false, new AsyncTask<Void, Void, Void>() {
       @Override
       protected Void doInBackground(Void... params) {
         try {

AndroidSDK/src/com/leanplum/internal/Util.java

@@ -91,6 +91,7 @@
  */
 public class Util {
   private static final Executor asyncExecutor = Executors.newCachedThreadPool();
+  private static final Executor singleThreadExecutor = Executors.newSingleThreadExecutor();
 
   private static final String ACCESS_WIFI_STATE_PERMISSION = "android.permission.ACCESS_WIFI_STATE";
 
@@ -723,9 +724,22 @@ public static <T> T multiIndex(Map<?, ?> map, Object... indices) {
     return CollectionUtil.uncheckedCast(current);
   }
 
-  public static <T> void executeAsyncTask(AsyncTask<T, ?, ?> task, T... params) {
+  /**
+   * Execute async task on single thread Executer or cached thread pool Executer.
+   *
+   * @param singleThread True if needs to be executed on single thread Executer, otherwise it will
+   * use cached thread pool Executer.
+   * @param task Async task to execute.
+   * @param params Params.
+   */
+  public static <T> void executeAsyncTask(boolean singleThread, AsyncTask<T, ?, ?> task,
+      T... params) {
     if (Build.VERSION.SDK_INT >= 11) {
-      task.executeOnExecutor(asyncExecutor, params);
+      if (singleThread) {
+        task.executeOnExecutor(singleThreadExecutor, params);
+      } else {
+        task.executeOnExecutor(asyncExecutor, params);
+      }
     } else {
       task.execute(params);
     }