Implement second part of dynamic DMaaP config

VESCollector app can now fetch CBS configuration and
rebuilt the part regarding sending events dynamically,
without restarting application.
Application will still be restarted by a .sh script,
if there were changes regarding collector.properties file.
The decision of whether dynamic configuration should be
triggered is now based on existence of env vars
CONSUL_HOST, CONFIG_BINDING_SERVICE, HOSTNAME,
not as previously on CBSPOLLTIME.
Frequency at which the config check should happen is
now exposed via property from collector.properties

Change-Id: I98ff160fa51d08d84a23c716d90ceaacbe17ada6
Signed-off-by: PawelSzalapski <pawel.szalapski@nokia.com>
Issue-ID: DCAEGEN2-519

1 files changed, 122 insertions, 0 deletions

diff --git a/src/main/java/org/onap/dcae/controller/ConfigFilesFacade.java b/src/main/java/org/onap/dcae/controller/ConfigFilesFacade.java
new file mode 100644
index 00000000..42155eda
--- /dev/null
+++ b/src/main/java/org/onap/dcae/controller/ConfigFilesFacade.java
@@ -0,0 +1,122 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * org.onap.dcaegen2.collectors.ves
+ * ================================================================================
+ * Copyright (C) 2017-2018 AT&T Intellectual Property. All rights reserved.
+ * Copyright (C) 2018 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.dcae.controller;
+
+import static io.vavr.API.Try;
+import static org.onap.dcae.commonFunction.event.publishing.VavrUtils.enhanceError;
+import static org.onap.dcae.commonFunction.event.publishing.VavrUtils.f;
+import static org.onap.dcae.commonFunction.event.publishing.VavrUtils.logError;
+import static org.onap.dcae.controller.Conversions.toList;
+
+import io.vavr.CheckedRunnable;
+import io.vavr.Tuple2;
+import io.vavr.collection.Map;
+import io.vavr.control.Try;
+import java.io.FileNotFoundException;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import org.apache.commons.configuration.ConfigurationException;
+import org.apache.commons.configuration.PropertiesConfiguration;
+import org.json.JSONObject;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+class ConfigFilesFacade {
+
+    private static Logger log = LoggerFactory.getLogger(ConfigFilesFacade.class);
+
+    private final Path dMaaPConfigPath;
+    private final Path propertiesPath;
+
+    public ConfigFilesFacade(Path dMaaPConfigPath, Path propertiesPath) {
+        this.dMaaPConfigPath = dMaaPConfigPath;
+        this.propertiesPath = propertiesPath;
+    }
+
+    Try<Map<String, String>> readCollectorProperties() {
+        log.info(f("Reading collector properties from path: '%s'", propertiesPath));
+        return Try(() -> readProperties())
+            .map(prop -> toList(prop.getKeys()).toMap(k -> k, k -> (String) prop.getProperty(k)))
+            .mapFailure(enhanceError("Unable to read properties configuration from path '%s'", propertiesPath))
+            .onFailure(logError(log))
+            .peek(props -> log.info(f("Read following collector properties: '%s'", props)));
+    }
+
+    Try<JSONObject> readDMaaPConfiguration() {
+        log.info(f("Reading DMaaP configuration from file: '%s'", dMaaPConfigPath));
+        return readFile(dMaaPConfigPath)
+            .recover(FileNotFoundException.class, __ -> "{}")
+            .mapFailure(enhanceError("Unable to read DMaaP configuration from file '%s'", dMaaPConfigPath))
+            .flatMap(Conversions::toJson)
+            .onFailure(logError(log))
+            .peek(props -> log.info(f("Read following DMaaP properties: '%s'", props)));
+    }
+
+    Try<Void> writeDMaaPConfiguration(JSONObject dMaaPConfiguration) {
+        log.info(f("Writing DMaaP configuration '%s' into file '%s'", dMaaPConfiguration, dMaaPConfigPath));
+        return writeFile(dMaaPConfigPath, indentConfiguration(dMaaPConfiguration.toString()))
+            .mapFailure(enhanceError("Could not save new DMaaP configuration to path '%s'", dMaaPConfigPath))
+            .onFailure(logError(log))
+            .peek(__ -> log.info("Written successfully"));
+    }
+
+
+    Try<Void> writeProperties(Map<String, String> properties) {
+        log.info(f("Writing properties configuration '%s' into file '%s'", properties, propertiesPath));
+        return Try.run(saveProperties(properties))
+            .mapFailure(enhanceError("Could not save properties to path '%s'", properties))
+            .onFailure(logError(log))
+            .peek(__ -> log.info("Written successfully"));
+    }
+
+    private Try<String> readFile(Path path) {
+        return Try(() -> new String(Files.readAllBytes(path), StandardCharsets.UTF_8))
+            .mapFailure(enhanceError("Could not read content from path: '%s'", path));
+    }
+
+    private Try<Void> writeFile(Path path, String content) {
+        return Try.run(() -> Files.write(path, content.getBytes()))
+            .mapFailure(enhanceError("Could not write content to path: '%s'", path));
+    }
+
+    private PropertiesConfiguration readProperties() throws ConfigurationException {
+        PropertiesConfiguration propertiesConfiguration = new PropertiesConfiguration();
+        propertiesConfiguration.load(propertiesPath.toFile());
+        return propertiesConfiguration;
+    }
+
+    private CheckedRunnable saveProperties(Map<String, String> properties) {
+        return () -> {
+            PropertiesConfiguration propertiesConfiguration = new PropertiesConfiguration(propertiesPath.toFile());
+            propertiesConfiguration.setEncoding(null);
+            for (Tuple2<String, String> property : properties) {
+                propertiesConfiguration.addProperty(property._1, property._2);
+            }
+            propertiesConfiguration.save();
+        };
+    }
+
+    private String indentConfiguration(String configuration) {
+        return new JSONObject(configuration).toString(4);
+    }
+
+}