Fix issues in policy-distribution

1) Creating a new thread for watching directory path for new file.
2) Updating distribution statistics from FileSystemReceptionHandler.

Change-Id: Ic539f2cad015f0756407fe910f309a2ea661a764
Issue-ID: POLICY-1437
Signed-off-by: ramverma <ram.krishna.verma@est.tech>

4 files changed, 123 insertions, 16 deletions

diff --git a/plugins/reception-plugins/src/main/java/org/onap/policy/distribution/reception/handling/file/FileClientHandler.java b/plugins/reception-plugins/src/main/java/org/onap/policy/distribution/reception/handling/file/FileClientHandler.java
new file mode 100644
index 00000000..f8e57747
--- /dev/null
+++ b/plugins/reception-plugins/src/main/java/org/onap/policy/distribution/reception/handling/file/FileClientHandler.java
@@ -0,0 +1,61 @@
+/*-
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2019 Nordix Foundation.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.distribution.reception.handling.file;
+
+import java.io.IOException;
+
+import org.onap.policy.common.logging.flexlogger.FlexLogger;
+import org.onap.policy.common.logging.flexlogger.Logger;
+
+/**
+ * This class implements Runnable interface for creating new thread which will be used as file watcher.
+ *
+ * @author Ram Krishna Verma (ram.krishna.verma@est.tech)
+ */
+public class FileClientHandler implements Runnable {
+
+    private static final Logger LOGGER = FlexLogger.getLogger(FileClientHandler.class);
+
+    private FileSystemReceptionHandler fileReceptionHandler;
+    private String watchPath;
+
+    /**
+     * Constructs an instance of {@link FileClientHandler} class.
+     *
+     * @param fileReceptionHandler the fileReceptionHandler
+     */
+    public FileClientHandler(final FileSystemReceptionHandler fileReceptionHandler, final String watchPath) {
+        this.fileReceptionHandler = fileReceptionHandler;
+        this.watchPath = watchPath;
+    }
+
+    /**
+     * {@inheritDoc}.
+     */
+    @Override
+    public void run() {
+        try {
+            fileReceptionHandler.initFileWatcher(watchPath);
+        } catch (final IOException ex) {
+            LOGGER.error(ex);
+        }
+    }
+}
diff --git a/plugins/reception-plugins/src/main/java/org/onap/policy/distribution/reception/handling/sdc/FileSystemReceptionHandler.java b/plugins/reception-plugins/src/main/java/org/onap/policy/distribution/reception/handling/file/FileSystemReceptionHandler.java
index 941cdd61..3cb167f3 100644
--- a/plugins/reception-plugins/src/main/java/org/onap/policy/distribution/reception/handling/sdc/FileSystemReceptionHandler.java
+++ b/plugins/reception-plugins/src/main/java/org/onap/policy/distribution/reception/handling/file/FileSystemReceptionHandler.java
@@ -1,6 +1,7 @@
 /*-
  * ============LICENSE_START=======================================================
  *  Copyright (C) 2018 Intel Corp. All rights reserved.
+ *  Copyright (C) 2019 Nordix Foundation.
  * ================================================================================
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -18,7 +19,7 @@
  * ============LICENSE_END=========================================================
  */
 
-package org.onap.policy.distribution.reception.handling.sdc;
+package org.onap.policy.distribution.reception.handling.file;
 
 import static java.nio.file.StandardWatchEventKinds.ENTRY_CREATE;
 
@@ -30,65 +31,85 @@ import java.nio.file.Paths;
 import java.nio.file.WatchEvent;
 import java.nio.file.WatchKey;
 import java.nio.file.WatchService;
+import java.util.concurrent.TimeUnit;
+import java.util.zip.ZipFile;
 
 import org.onap.policy.common.logging.flexlogger.FlexLogger;
 import org.onap.policy.common.logging.flexlogger.Logger;
-
 import org.onap.policy.common.parameters.ParameterService;
 import org.onap.policy.distribution.model.Csar;
 import org.onap.policy.distribution.reception.decoding.PolicyDecodingException;
 import org.onap.policy.distribution.reception.handling.AbstractReceptionHandler;
+import org.onap.policy.distribution.reception.statistics.DistributionStatisticsManager;
 
 /**
  * Handles reception of inputs from File System which can be used to decode policies.
  */
 public class FileSystemReceptionHandler extends AbstractReceptionHandler {
-    private boolean running = false;
+
     private static final Logger LOGGER = FlexLogger.getLogger(FileSystemReceptionHandler.class);
+    private boolean running = false;
 
+    /**
+     * {@inheritDoc}.
+     */
     @Override
     protected void initializeReception(final String parameterGroupName) {
         LOGGER.debug("FileSystemReceptionHandler init...");
         try {
             final FileSystemReceptionHandlerConfigurationParameterGroup handlerParameters =
-                                    ParameterService.get(parameterGroupName);
-            main(handlerParameters.getWatchPath());
+                    ParameterService.get(parameterGroupName);
+            final FileClientHandler fileClientHandler = new FileClientHandler(this, handlerParameters.getWatchPath());
+            final Thread fileWatcherThread = new Thread(fileClientHandler);
+            fileWatcherThread.start();
         } catch (final Exception ex) {
             LOGGER.error(ex);
         }
-        running = false;
-        LOGGER.debug("FileSystemReceptionHandler main loop exited...");
     }
 
+    /**
+     * {@inheritDoc}.
+     */
     @Override
     public void destroy() {
-        // Tear down subscription etc
         running = false;
     }
 
+    /**
+     * Method to check the running status of file watcher thread.
+     *
+     * @return the running status
+     */
     public boolean isRunning() {
         return running;
     }
 
     /**
-     * Main entry point.
-     * 
+     * Initialize the file watcher thread.
+     *
      * @param watchPath Path to watch
      */
-    public void main(String watchPath) throws IOException {
+    public void initFileWatcher(final String watchPath) throws IOException {
         try (final WatchService watcher = FileSystems.getDefault().newWatchService()) {
             final Path dir = Paths.get(watchPath);
             dir.register(watcher, ENTRY_CREATE);
             LOGGER.debug("Watch Service registered for dir: " + dir.getFileName());
-            startMainLoop(watcher, dir);
+            startWatchService(watcher, dir);
         } catch (final InterruptedException ex) {
             LOGGER.debug(ex);
             Thread.currentThread().interrupt();
         }
     }
 
+    /**
+     * Method to keep watching the given path for any new file created.
+     *
+     * @param watcher the watcher
+     * @param dir the watch directory
+     * @throws InterruptedException if it occurs
+     */
     @SuppressWarnings("unchecked")
-    protected void startMainLoop(WatchService watcher, Path dir) throws InterruptedException {
+    protected void startWatchService(final WatchService watcher, final Path dir) throws InterruptedException {
         WatchKey key;
         running = true;
         while (running) {
@@ -98,7 +119,10 @@ public class FileSystemReceptionHandler extends AbstractReceptionHandler {
                 final WatchEvent<Path> ev = (WatchEvent<Path>) event;
                 final Path fileName = ev.context();
                 LOGGER.debug("new CSAR found: " + fileName);
-                createPolicyInputAndCallHandler(dir.toString() + File.separator + fileName.toString());
+                DistributionStatisticsManager.updateTotalDistributionCount();
+                final String fullFilePath = dir.toString() + File.separator + fileName.toString();
+                waitForFileToBeReady(fullFilePath);
+                createPolicyInputAndCallHandler(fullFilePath);
                 LOGGER.debug("CSAR complete: " + fileName);
             }
             final boolean valid = key.reset();
@@ -109,12 +133,34 @@ public class FileSystemReceptionHandler extends AbstractReceptionHandler {
         }
     }
 
+    /**
+     * Method to create policy input & call policy handlers.
+     *
+     * @param fileName the filename
+     */
     protected void createPolicyInputAndCallHandler(final String fileName) {
         try {
             final Csar csarObject = new Csar(fileName);
+            DistributionStatisticsManager.updateTotalDownloadCount();
             inputReceived(csarObject);
+            DistributionStatisticsManager.updateDownloadSuccessCount();
+            DistributionStatisticsManager.updateDistributionSuccessCount();
         } catch (final PolicyDecodingException ex) {
+            DistributionStatisticsManager.updateDownloadFailureCount();
+            DistributionStatisticsManager.updateDistributionFailureCount();
             LOGGER.error(ex);
         }
     }
+
+    private void waitForFileToBeReady(final String fullFilePath) throws InterruptedException {
+        boolean flag = true;
+        while (flag) {
+            TimeUnit.MILLISECONDS.sleep(100);
+            try (ZipFile zipFile = new ZipFile(fullFilePath)) {
+                flag = false;
+            } catch (final IOException exp) {
+                LOGGER.error("file is not ready for reading, wait for sometime and try again", exp);
+            }
+        }
+    }
 }
diff --git a/plugins/reception-plugins/src/main/java/org/onap/policy/distribution/reception/handling/sdc/FileSystemReceptionHandlerConfigurationParameterBuilder.java b/plugins/reception-plugins/src/main/java/org/onap/policy/distribution/reception/handling/file/FileSystemReceptionHandlerConfigurationParameterBuilder.java
index 37a16980..693ff0ec 100644
--- a/plugins/reception-plugins/src/main/java/org/onap/policy/distribution/reception/handling/sdc/FileSystemReceptionHandlerConfigurationParameterBuilder.java
+++ b/plugins/reception-plugins/src/main/java/org/onap/policy/distribution/reception/handling/file/FileSystemReceptionHandlerConfigurationParameterBuilder.java
@@ -18,7 +18,7 @@
  * ============LICENSE_END=========================================================
  */
 
-package org.onap.policy.distribution.reception.handling.sdc;
+package org.onap.policy.distribution.reception.handling.file;
 
 /**
  * This class builds an instance of {@link FileSystemReceptionHandlerConfigurationParameterGroup} class.
diff --git a/plugins/reception-plugins/src/main/java/org/onap/policy/distribution/reception/handling/sdc/FileSystemReceptionHandlerConfigurationParameterGroup.java b/plugins/reception-plugins/src/main/java/org/onap/policy/distribution/reception/handling/file/FileSystemReceptionHandlerConfigurationParameterGroup.java
index 457cd5ea..dd50dc78 100644
--- a/plugins/reception-plugins/src/main/java/org/onap/policy/distribution/reception/handling/sdc/FileSystemReceptionHandlerConfigurationParameterGroup.java
+++ b/plugins/reception-plugins/src/main/java/org/onap/policy/distribution/reception/handling/file/FileSystemReceptionHandlerConfigurationParameterGroup.java
@@ -18,7 +18,7 @@
  * ============LICENSE_END=========================================================
  */
 
-package org.onap.policy.distribution.reception.handling.sdc;
+package org.onap.policy.distribution.reception.handling.file;
 
 import java.io.File;