[ONOS-4176] Extract InfluxDB access config in a separate service

With existing implementation, influxDB access related configuration
should be done in both reporter and retriever which may cause
potential inconsistency. With this commit, both reporter and
retriever refer to access configuration from InfluxDbMetricsConfig
so that we do not need to configure access parameters two times.

Change-Id: I25159abb24e46d9593ef71224da3f79e3687d36c
diff --git a/apps/influxdbmetrics/src/main/java/org/onosproject/influxdbmetrics/DefaultInfluxDbMetricsReporter.java b/apps/influxdbmetrics/src/main/java/org/onosproject/influxdbmetrics/DefaultInfluxDbMetricsReporter.java
new file mode 100644
index 0000000..c1be6f6
--- /dev/null
+++ b/apps/influxdbmetrics/src/main/java/org/onosproject/influxdbmetrics/DefaultInfluxDbMetricsReporter.java
@@ -0,0 +1,229 @@
+/*
+ * 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.influxdbmetrics;
+
+import com.codahale.metrics.MetricRegistry;
+import com.izettle.metrics.influxdb.InfluxDbHttpSender;
+import com.izettle.metrics.influxdb.InfluxDbReporter;
+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.apache.felix.scr.annotations.Service;
+import org.onlab.metrics.MetricsService;
+import org.onlab.util.Tools;
+import org.onosproject.cfg.ComponentConfigService;
+import org.onosproject.cluster.ClusterService;
+import org.onosproject.cluster.ControllerNode;
+import org.onosproject.core.CoreService;
+import org.osgi.service.component.ComponentContext;
+import org.slf4j.Logger;
+
+import java.util.Dictionary;
+import java.util.concurrent.TimeUnit;
+
+import static org.slf4j.LoggerFactory.getLogger;
+
+/**
+ * A Metric reporter that reports all metrics value to influxDB server.
+ */
+@Component(immediate = true)
+@Service
+public class DefaultInfluxDbMetricsReporter implements InfluxDbMetricsReporter {
+    private final Logger log = getLogger(getClass());
+
+    private static final int REPORT_PERIOD = 1;
+    private static final TimeUnit REPORT_TIME_UNIT = TimeUnit.MINUTES;
+
+    private static final String DEFAULT_PROTOCOL = "http";
+    private static final String DEFAULT_METRIC_NAMES = "default";
+    private static final String SEPARATOR = ":";
+    private static final int DEFAULT_CONN_TIMEOUT = 1000;
+    private static final int DEFAULT_READ_TIMEOUT = 1000;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected CoreService coreService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected MetricsService metricsService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected ComponentConfigService cfgService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected ClusterService clusterService;
+
+    @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 in third party monitoring " +
+                    "server; default metric names are 'default'")
+    protected String metricNames = DEFAULT_METRIC_NAMES;
+
+    protected String address;
+    protected int port;
+    protected String database;
+    protected String username;
+    protected String password;
+
+    private InfluxDbReporter influxDbReporter;
+    private InfluxDbHttpSender influxDbHttpSender;
+
+    @Activate
+    public void activate() {
+        cfgService.registerProperties(getClass());
+        coreService.registerApplication("org.onosproject.influxdbmetrics");
+
+        log.info("Started");
+    }
+
+    @Deactivate
+    public void deactivate() {
+        cfgService.unregisterProperties(getClass(), false);
+
+        log.info("Stopped");
+    }
+
+    @Modified
+    public void modified(ComponentContext context) {
+        readComponentConfiguration(context);
+        restartReport();
+    }
+
+    @Override
+    public void startReport() {
+        try {
+            influxDbHttpSender = new InfluxDbHttpSender(DEFAULT_PROTOCOL, address,
+                    port, database, username + SEPARATOR + password, REPORT_TIME_UNIT,
+                    DEFAULT_CONN_TIMEOUT, DEFAULT_READ_TIMEOUT);
+            MetricRegistry mr = metricsService.getMetricRegistry();
+            influxDbReporter = InfluxDbReporter.forRegistry(addHostPrefix(filter(mr)))
+                    .convertRatesTo(TimeUnit.SECONDS)
+                    .convertDurationsTo(TimeUnit.MILLISECONDS)
+                    .build(influxDbHttpSender);
+            influxDbReporter.start(REPORT_PERIOD, REPORT_TIME_UNIT);
+            log.info("Start to report metrics to influxDB.");
+        } catch (Exception e) {
+            log.error("Fail to connect to given influxDB server!");
+        }
+    }
+
+    @Override
+    public void stopReport() {
+        influxDbReporter.stop();
+        influxDbHttpSender = null;
+        influxDbReporter = null;
+        log.info("Stop reporting metrics to influxDB.");
+    }
+
+    @Override
+    public void restartReport() {
+        stopReport();
+        startReport();
+    }
+
+    @Override
+    public void config(String address, int port, String database,
+                       String username, String password) {
+        this.address = address;
+        this.port = port;
+        this.database = database;
+        this.username = username;
+        this.password = password;
+    }
+
+    /**
+     * 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;
+        }
+    }
+
+    /**
+     * Appends node IP prefix to all performance metrics.
+     *
+     * @param metricRegistry original metric registry
+     * @return prefix added metric registry
+     */
+    protected MetricRegistry addHostPrefix(MetricRegistry metricRegistry) {
+        MetricRegistry moddedRegistry = new MetricRegistry();
+        ControllerNode node = clusterService.getLocalNode();
+        String prefix = node.id().id() + ".";
+        metricRegistry.getNames().stream().forEach(name ->
+                moddedRegistry.register(prefix + name, metricRegistry.getMetrics().get(name)));
+
+        return moddedRegistry;
+    }
+
+    /**
+     * 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 metricNameStr = Tools.get(properties, "metricNames");
+        metricNames = metricNameStr != null ? metricNameStr : DEFAULT_METRIC_NAMES;
+        log.info("Configured. Metric name is {}", metricNames);
+
+        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");
+        }
+    }
+}