1 files changed, 111 insertions, 0 deletions
diff --git a/src/main/java/org/onap/pnfsimulator/filesystem/WatcherEventProcessor.java b/src/main/java/org/onap/pnfsimulator/filesystem/WatcherEventProcessor.java
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+/*-
+ * ============LICENSE_START=======================================================
+ * Simulator
+ * ================================================================================
+ * Copyright (C) 2019 Nokia. All rights reserved.
+ * ================================================================================
+ * 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.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.pnfsimulator.filesystem;
+
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.StandardWatchEventKinds;
+import java.nio.file.WatchEvent;
+import java.nio.file.WatchEvent.Kind;
+import java.time.Instant;
+import java.util.Arrays;
+import java.util.Optional;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
+import lombok.extern.slf4j.Slf4j;
+import org.bson.BSONException;
+import org.bson.json.JsonParseException;
+import org.onap.pnfsimulator.db.Storage;
+import org.onap.pnfsimulator.template.Template;
+import org.bson.Document;
+
+@Slf4j
+public enum WatcherEventProcessor {
+    CREATED(StandardWatchEventKinds.ENTRY_CREATE) {
+        @Override
+        public void processEvent(Path path, Storage<Template> storage) throws IOException {
+            String content = getContent(path);
+            String fileName = path.getFileName().toString();
+            Document documentsContent = Document.parse(content);
+            storage.persist(new Template(fileName, documentsContent, Instant.now().getNano()));
+            log.info("DB record created for template: " + fileName);
+        }
+    },
+    MODIFIED(StandardWatchEventKinds.ENTRY_MODIFY) {
+        @Override
+        public void processEvent(Path path, Storage<Template> storage) throws IOException {
+            String fileName = path.getFileName().toString();
+            String content = getContent(path);
+            Document documentsContent = Document.parse(content);
+            Template template = storage.get(fileName).orElse(new Template(fileName, documentsContent, Instant.now().getNano()));
+            template.setContent(documentsContent);
+            storage.persist(template);
+            log.info("DB record modified for template: " + fileName);
+        }
+    },
+    DELETED(StandardWatchEventKinds.ENTRY_DELETE) {
+        @Override
+        public void processEvent(Path path, Storage<Template> storage) {
+            String fileName = path.getFileName().toString();
+            storage.delete(fileName);
+            log.info("DB record deleted for template: " + fileName);
+        }
+    };
+
+    private final Kind<Path> pathKind;
+
+    String getContent(Path path) throws IOException {
+        try (Stream<String> lines = Files.lines(path, StandardCharsets.UTF_8)) {
+            return lines.collect(Collectors.joining(System.lineSeparator()));
+        } catch (IOException e) {
+            log.error("Could not get content due to: " + e.getMessage() + " " + e.getCause(), e);
+            throw e;
+        }
+    }
+
+    WatcherEventProcessor(Kind<Path> pathKind) {
+        this.pathKind = pathKind;
+    }
+
+    public abstract void processEvent(Path templateName, Storage<Template> storage) throws IOException;
+
+    static void process(WatchEvent<?> event, Storage<Template> storage, Path templatesDir) {
+        Optional<WatcherEventProcessor> watcherEventProcessor = getWatcherEventProcessor(event);
+        watcherEventProcessor.ifPresent(processor -> {
+            try {
+                final Path templatePath = templatesDir.resolve((Path) event.context());
+                processor.processEvent(templatePath, storage);
+            } catch (IOException e) {
+                log.error("Error during processing DB record for template.", e);
+            } catch (BSONException | JsonParseException e) {
+                log.error("Invalid JSON format provided for template.", e);
+            }
+        });
+    }
+
+    private static Optional<WatcherEventProcessor> getWatcherEventProcessor(WatchEvent<?> event) {
+        return Arrays.stream(values()).filter(value -> value.pathKind.equals(event.kind())).findFirst();
+    }
+
+}