Make FileSystemReceptionHandler more tolerant

Make FileSystemReceptionHandler tolerant of exceptions thrown when
parsing tosca template and be able to handle new incoming csar.

Also added the unit test for FileSystemReceptionHandler.

Change-Id: I0f1647f6f952576a8e61adca4d027990706d1411
Issue-ID: POLICY-837
Signed-off-by: Lianhao Lu <lianhao.lu@intel.com>
(cherry picked from commit 70f9f24e6ed39a6ddb4afef02516af624f50079d)

2 files changed, 24 insertions, 11 deletions

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/sdc/FileSystemReceptionHandler.java
index 9ac21550..b1a95fac 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/sdc/FileSystemReceptionHandler.java
@@ -23,6 +23,7 @@ package org.onap.policy.distribution.reception.handling.sdc;
 import static java.nio.file.StandardWatchEventKinds.ENTRY_CREATE;
 
 import java.io.File;
+import java.io.IOException;
 import java.nio.file.FileSystems;
 import java.nio.file.Path;
 import java.nio.file.Paths;
@@ -52,9 +53,10 @@ public class FileSystemReceptionHandler extends AbstractReceptionHandler {
             final FileSystemReceptionHandlerConfigurationParameterGroup handlerParameters =
                                     ParameterService.get(parameterGroupName);
             main(handlerParameters.getWatchPath());
-        } catch (final PolicyDecodingException ex) {
-            LOGGER.debug(ex);
+        } catch (final Exception ex) {
+            LOGGER.error(ex);
         }
+        LOGGER.debug("FileSystemReceptionHandler main loop exited...");
     }
 
     @Override
@@ -67,10 +69,9 @@ public class FileSystemReceptionHandler extends AbstractReceptionHandler {
      * Main entry point.
      * 
      * @param watchPath Path to watch
-     * @throws PolicyDecodingException Decoding exception
      */
     @SuppressWarnings("unchecked")
-    public void main(String watchPath) throws PolicyDecodingException {
+    public void main(String watchPath) {
         try (final WatchService watcher = FileSystems.getDefault().newWatchService()) {
             final Path dir = Paths.get(watchPath);
 
@@ -85,25 +86,31 @@ public class FileSystemReceptionHandler extends AbstractReceptionHandler {
                     Thread.currentThread().interrupt();
                     return;
                 }
+
                 for (final WatchEvent<?> event : key.pollEvents()) {
                     final WatchEvent.Kind<?> kind = event.kind();
                     final WatchEvent<Path> ev = (WatchEvent<Path>) event;
                     final Path fileName = ev.context();
-                    LOGGER.debug("new CSAR found: " + kind.name() + ": " + fileName);
-                    createPolicyInputAndCallHandler(dir.toString() + File.separator + fileName.toString());
-                    LOGGER.debug("CSAR complete: " + kind.name() + ": " + fileName);
+                    try {
+                        LOGGER.debug("new CSAR found: " + kind.name() + ": " + fileName);
+                        createPolicyInputAndCallHandler(dir.toString() + File.separator + fileName.toString());
+                        LOGGER.debug("CSAR complete: " + kind.name() + ": " + fileName);
+                    } catch (final PolicyDecodingException ex) {
+                        LOGGER.error(ex);
+                    }
                 }
                 final boolean valid = key.reset();
                 if (!valid) {
+                    LOGGER.error("Watch key no longer valid!");
                     break;
                 }
             }
-        } catch (final Exception ex) {
+        } catch (final IOException ex) {
             LOGGER.error(ex);
         }
     }
 
-    private void createPolicyInputAndCallHandler(final String fileName) throws PolicyDecodingException {
+    protected void createPolicyInputAndCallHandler(final String fileName) throws PolicyDecodingException {
         final Csar csarObject = new Csar(fileName);
         inputReceived(csarObject);
     }
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/sdc/FileSystemReceptionHandlerConfigurationParameterGroup.java
index 98f3c6a4..457cd5ea 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/sdc/FileSystemReceptionHandlerConfigurationParameterGroup.java
@@ -68,8 +68,14 @@ public class FileSystemReceptionHandlerConfigurationParameterGroup extends Recep
      */
     private void validatePathElement(final GroupValidationResult validationResult, final String element,
             final String elementName) {
-        File file = new File(element);
-        if (!(file.exists() && file.isDirectory())) {
+        boolean valid = false;
+        if (element != null) {
+            File file = new File(element);
+            if (file.exists() && file.isDirectory()) {
+                valid = true;
+            }
+        }
+        if (!valid) {
             validationResult.setResult(elementName, ValidationStatus.INVALID,
                     elementName + " must be a valid directory");
         }