Checks if URL is reachable before uploading the logs

README.md

@@ -90,6 +90,8 @@ Add the following inside the application manifest (inside `<application>`):
  * **LogseneRequiresUnmeteredNetwork**: if logs should be shipped only on unmetered network connection
  * **LogseneRequiresDeviceIdle**: if logs should be shipped only when device is idle
  * **LogseneRequiresBatteryNotLow**: if logs should be shipped only when battery is not low
+ * **LogseneCheckUnreachableUrl**: checks if url is reachable before pushing logs
+ * **LogseneUnreachableUrlTimeout**: socket timout to check if url is reachable
  * **LogseneAutomaticLocationEnabled**: if logs should be automatically enriched with device location information. See the **Enriching Logs with Location** section for more details.
 
 Example Application

logseneandroid/src/main/java/com/sematext/logseneandroid/LogWorker.java

@@ -29,7 +29,10 @@ public class LogWorker extends Worker {
 
   private LogseneClient client;
   private String appToken;
+  private String receiverUrl;
   private String type;
+  private boolean checkUnreachableUrl;
+  private int unreachableUrlTimeout;
   private final Context context;
 
   private SqliteObjectQueue preflightQueue;
@@ -41,10 +44,13 @@ public LogWorker(@NonNull Context context, @NonNull WorkerParameters params) {
 
   @Override
   public Result doWork() {
+    receiverUrl = getInputData().getString(Logsene.KEY_RECEIVERURL);
     appToken = getInputData().getString(Logsene.KEY_APPTOKEN);
     type = getInputData().getString(Logsene.KEY_TYPE);
+    checkUnreachableUrl = getInputData().getBoolean(Logsene.KEY_CHECK_UNREACHABLE_URL,false);
+    unreachableUrlTimeout = getInputData().getInt(Logsene.KEY_UNREACHABLE_URL_TIMEOUT, Logsene.DEFAULT_UNREACHABLE_TIMEOUT);
 
-    this.client = new LogseneClient(getInputData().getString(Logsene.KEY_RECEIVERURL), appToken);
+    this.client = new LogseneClient(receiverUrl, appToken);
     this.preflightQueue = new SqliteObjectQueue(context);
 
     long size = preflightQueue.size();
@@ -96,6 +102,10 @@ private boolean attemptExecute(Bulk bulk, int leftAttempts) {
     leftAttempts -= 1;
     try {
       Log.d(LOG_TAG, "Attempting to send bulk request");
+      if (checkUnreachableUrl && !Utils.isURLReachable(receiverUrl, unreachableUrlTimeout)){
+        Log.e(LOG_TAG, "Unreachable URL");
+        return attemptExecute(bulk, leftAttempts);
+      }
       ApiResponse result = client.execute(bulk);
       if (!result.isSuccessful()) {
         Log.e(LOG_TAG, String.format("Bad status code (%d) returned from api. Response: %s",

logseneandroid/src/main/java/com/sematext/logseneandroid/Logsene.java

@@ -32,6 +32,9 @@ public class Logsene {
   public static final String KEY_APPTOKEN = "LOGSENE_APPTOKEN";
   public static final String KEY_TYPE = "LOGSENE_TYPE";
 
+  public static final String KEY_CHECK_UNREACHABLE_URL = "LOGSENE_CHECK_UNREACHABLE_URL";
+  public static final String KEY_UNREACHABLE_URL_TIMEOUT = "LOGSENE_UNREACHABLE_URL_TIMEOUT";
+  public static final int DEFAULT_UNREACHABLE_TIMEOUT = 500;
   private final String TAG = getClass().getSimpleName();
   private final String FLUSH_WORKER_TAG = "com.sematext.android.LogWorker.unconstrained";
   private final String INTERVAL_WORKER_TAG = "com.sematext.android.LogWorker.interval";
@@ -86,6 +89,8 @@ public class Logsene {
   private boolean sendRequiresBatteryNotLow;
   private boolean isActive;
   private boolean automaticLocationEnabled;
+  private boolean checkUnreachableUrl;
+  private int unreachableUrlTimeout;
   private LogseneLocationListener locationListener;
 
   // Private constructor - no instances.
@@ -406,6 +411,8 @@ private void config(Context context) {
     sendRequiresDeviceIdle = data.getBoolean("LogseneSendRequiresDeviceIdle", false);
     sendRequiresBatteryNotLow = data.getBoolean("LogseneSendRequiresBatteryNotLow", false);
     automaticLocationEnabled = data.getBoolean("LogseneAutomaticLocationEnabled", false);
+    checkUnreachableUrl = data.getBoolean("LogseneCheckUnreachableUrl", false);
+    unreachableUrlTimeout = data.getInt("LogseneUnreachableUrlTimeout", DEFAULT_UNREACHABLE_TIMEOUT);
 
     Log.d(TAG, String.format("Logsene is configured:\n"
                     + "  Type:                                   %s\n"
@@ -426,6 +433,8 @@ private Data getWorkerData() {
             .putString(KEY_RECEIVERURL, receiverUrl)
             .putString(KEY_APPTOKEN, appToken)
             .putString(KEY_TYPE, type)
+            .putBoolean(KEY_CHECK_UNREACHABLE_URL, checkUnreachableUrl)
+            .putInt(KEY_UNREACHABLE_URL_TIMEOUT, unreachableUrlTimeout)
             .build();
   }
 

logseneandroid/src/main/java/com/sematext/logseneandroid/Utils.java

@@ -6,8 +6,12 @@
 
 import androidx.core.app.ActivityCompat;
 
+import java.io.IOException;
 import java.io.PrintWriter;
 import java.io.StringWriter;
+import java.net.InetSocketAddress;
+import java.net.Socket;
+import java.net.URL;
 import java.text.SimpleDateFormat;
 import java.util.Date;
 import java.util.Locale;
@@ -61,4 +65,23 @@ public static boolean checkLocationPermissions(Context context) {
     return finePermissionState == PackageManager.PERMISSION_GRANTED ||
             coarsePermissionState == PackageManager.PERMISSION_GRANTED;
   }
+
+  /**
+   * @param url URL
+   * @param timeout for the socket connection
+   * @return <code>true</code> if url is reachable
+   */
+  public static boolean isURLReachable(String url, int timeout) {
+    try {
+      final URL u  = new URL(url);
+      final Socket socket = new Socket();
+      socket.setSoTimeout(timeout);
+      socket.connect(new InetSocketAddress(u.getHost(), 80),timeout);
+      boolean isConnected = socket.isConnected();
+      socket.close();
+      return isConnected;
+    } catch (IOException e){
+      return false;
+    }
+  }
 }