[ONOS-4127] Backup metric service to ganglia monitoring server

- Initial implementation of metric service reporter
- Unit test for metric service reporter
- Bump up metric lib from 3.1.0 to 3.1.2

Change-Id: Ia178df759d671dfc15cffaacb09d5279ad3d9ad8
diff --git a/apps/metricsreporter/src/main/java/org/onosproject/metrics/reporter/GangliaMetricsReporter.java b/apps/metricsreporter/src/main/java/org/onosproject/metrics/reporter/GangliaMetricsReporter.java
new file mode 100644
index 0000000..f2f48f4
--- /dev/null
+++ b/apps/metricsreporter/src/main/java/org/onosproject/metrics/reporter/GangliaMetricsReporter.java
@@ -0,0 +1,222 @@
+/*
+ * Copyright 2016 Open Networking Laboratory
+ *
+ * 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.
+ */
+package org.onosproject.metrics.reporter;
+
+import com.codahale.metrics.MetricRegistry;
+import com.codahale.metrics.ganglia.GangliaReporter;
+import info.ganglia.gmetric4j.gmetric.GMetric;
+import org.apache.commons.lang.StringUtils;
+import org.apache.felix.scr.annotations.Activate;
+import org.apache.felix.scr.annotations.Component;
+import org.apache.felix.scr.annotations.Deactivate;
+import org.apache.felix.scr.annotations.Modified;
+import org.apache.felix.scr.annotations.Property;
+import org.apache.felix.scr.annotations.Reference;
+import org.apache.felix.scr.annotations.ReferenceCardinality;
+import org.onlab.metrics.MetricsService;
+import org.onlab.util.Tools;
+import org.onosproject.cfg.ComponentConfigService;
+import org.onosproject.core.ApplicationId;
+import org.onosproject.core.CoreService;
+import org.osgi.service.component.ComponentContext;
+import org.slf4j.Logger;
+
+import java.io.IOException;
+import java.util.Dictionary;
+import java.util.concurrent.TimeUnit;
+
+import static org.slf4j.LoggerFactory.getLogger;
+
+/**
+ * A metric report that reports all metrics value to ganglia monitoring server.
+ */
+@Component(immediate = true)
+public class GangliaMetricsReporter implements MetricsReporter {
+    private final Logger log = getLogger(getClass());
+
+    // we will use uni-cast mode to transfer the metrics value by default
+    private static final GMetric.UDPAddressingMode GANGLIA_MODE =
+                         GMetric.UDPAddressingMode.UNICAST;
+    private static final int REPORT_PERIOD = 1;
+    private static final TimeUnit REPORT_TIME_UNIT = TimeUnit.MINUTES;
+
+    private static final String DEFAULT_ADDRESS = "localhost";
+    private static final int DEFAULT_PORT = 8649;
+    private static final int DEFAULT_TTL = 1;
+    private static final String DEFAULT_METRIC_NAMES = "default";
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected CoreService coreService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected MetricsService metricsService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected ComponentConfigService cfgService;
+
+    @Property(name = "monitorAll", boolValue = true,
+              label = "Enable to monitor all of metrics stored in metric registry default is true")
+    protected boolean monitorAll = true;
+
+    @Property(name = "metricNames", value = DEFAULT_METRIC_NAMES,
+              label = "Names of metric to be monitored; default metric names are 'default'")
+    protected String metricNames = DEFAULT_METRIC_NAMES;
+
+    @Property(name = "address", value = DEFAULT_ADDRESS,
+              label = "IP address of ganglia monitoring server; default is localhost")
+    protected String address = DEFAULT_ADDRESS;
+
+    @Property(name = "port", intValue = DEFAULT_PORT,
+              label = "Port number of ganglia monitoring server; default is 8649")
+    protected int port = DEFAULT_PORT;
+
+    @Property(name = "ttl", intValue = DEFAULT_TTL,
+              label = "TTL value of ganglia monitoring server; default is 1")
+    protected int ttl = DEFAULT_TTL;
+
+    private ApplicationId appId;
+    private GMetric ganglia;
+    private GangliaReporter gangliaReporter;
+
+    @Activate
+    public void activate() {
+        cfgService.registerProperties(getClass());
+        appId = coreService.registerApplication("org.onosproject.metrics.reporter");
+
+        startReport();
+        log.info("Started");
+    }
+
+    @Deactivate
+    public void deactivate() {
+        cfgService.unregisterProperties(getClass(), false);
+
+        stopReport();
+        log.info("Stopped");
+    }
+
+    @Modified
+    public void modified(ComponentContext context) {
+        readComponentConfiguration(context);
+        stopReport();
+        startReport();
+    }
+
+    @Override
+    public void startReport() {
+        try {
+            ganglia = new GMetric(address, port, GANGLIA_MODE, ttl);
+
+            MetricRegistry mr = metricsService.getMetricRegistry();
+
+            gangliaReporter = GangliaReporter.forRegistry(filter(mr))
+                    .convertRatesTo(TimeUnit.SECONDS)
+                    .convertDurationsTo(TimeUnit.MILLISECONDS)
+                    .build(ganglia);
+            gangliaReporter.start(REPORT_PERIOD, REPORT_TIME_UNIT);
+        } catch (IOException e) {
+            log.error("Fail to connect to given ganglia server!");
+        }
+    }
+
+    @Override
+    public void stopReport() {
+        gangliaReporter.stop();
+        ganglia = null;
+        gangliaReporter = null;
+    }
+
+    /**
+     * Filters the metrics to only include a set of the given metrics.
+     *
+     * @param metricRegistry original metric registry
+     * @return filtered metric registry
+     */
+    protected MetricRegistry filter(MetricRegistry metricRegistry) {
+        if (!monitorAll) {
+            final MetricRegistry filtered = new MetricRegistry();
+            metricRegistry.getNames().stream().filter(name ->
+                    containsName(name, metricNames)).forEach(name ->
+                    filtered.register(name, metricRegistry.getMetrics().get(name)));
+            return filtered;
+        } else {
+            return metricRegistry;
+        }
+    }
+
+    /**
+     * Looks up whether the metric name contains the given prefix keywords.
+     * Note that the keywords are separated with comma as delimiter
+     *
+     * @param full the original metric name that to be compared with
+     * @param prefixes the prefix keywords that are matched against with the metric name
+     * @return boolean value that denotes whether the metric name starts with the given prefix
+     */
+    protected boolean containsName(String full, String prefixes) {
+        String[] prefixArray = StringUtils.split(prefixes, ",");
+        for (String prefix : prefixArray) {
+            if (StringUtils.startsWith(full, StringUtils.trimToEmpty(prefix))) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    /**
+     * Extracts properties from the component configuration context.
+     *
+     * @param context the component context
+     */
+    private void readComponentConfiguration(ComponentContext context) {
+        Dictionary<?, ?> properties = context.getProperties();
+
+        String addressStr = Tools.get(properties, "address");
+        address = addressStr != null ? addressStr : DEFAULT_ADDRESS;
+        log.info("Configured. Ganglia server address is {}", address);
+
+        String metricNameStr = Tools.get(properties, "metricNames");
+        metricNames = metricNameStr != null ? metricNameStr : DEFAULT_METRIC_NAMES;
+        log.info("Configured. Metric name is {}", metricNames);
+
+        Integer portConfigured = Tools.getIntegerProperty(properties, "port");
+        if (portConfigured == null) {
+            port = DEFAULT_PORT;
+            log.info("Ganglia port is not configured, default value is {}", port);
+        } else {
+            port = portConfigured;
+            log.info("Configured. Ganglia port is configured to {}", port);
+        }
+
+        Integer ttlConfigured = Tools.getIntegerProperty(properties, "ttl");
+        if (ttlConfigured == null) {
+            ttl = DEFAULT_TTL;
+            log.info("Ganglia TTL is not configured, default value is {}", ttl);
+        } else {
+            ttl = ttlConfigured;
+            log.info("Configured. Ganglia TTL is configured to {}", ttl);
+        }
+
+        Boolean monitorAllEnabled = Tools.isPropertyEnabled(properties, "monitorAll");
+        if (monitorAllEnabled == null) {
+            log.info("Monitor all metrics is not configured, " +
+                     "using current value of {}", monitorAll);
+        } else {
+            monitorAll = monitorAllEnabled;
+            log.info("Configured. Monitor all metrics is {}",
+                    monitorAll ? "enabled" : "disabled");
+        }
+    }
+}