[ISSUE#173]Connect Exporter for Prometheus

connectors/rocketmq-connect-metrics-exporter/pom.xml

@@ -0,0 +1,47 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <groupId>org.apache.rocketmq</groupId>
+    <artifactId>rocketmq-connect-metrics-exporter</artifactId>
+    <version>1.0-SNAPSHOT</version>
+    <name>rocketmq-connect-metrics-exporter</name>
+
+
+    <properties>
+        <maven.compiler.source>1.8</maven.compiler.source>
+        <maven.compiler.target>1.8</maven.compiler.target>
+        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
+        <openmessaging.connector.version>0.1.3</openmessaging.connector.version>
+    </properties>
+
+    <dependencies>
+        <dependency>
+            <groupId>io.openmessaging</groupId>
+            <artifactId>openmessaging-connector</artifactId>
+            <version>${openmessaging.connector.version}</version>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <version>3.6.1</version>
+                <configuration>
+                    <source>${maven.compiler.source}</source>
+                    <target>${maven.compiler.target}</target>
+                    <compilerVersion>${maven.compiler.source}</compilerVersion>
+                    <showDeprecation>true</showDeprecation>
+                    <showWarnings>true</showWarnings>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
+
+
+</project>

connectors/rocketmq-connect-metrics-exporter/src/main/java/org/apache/rocket/connect/metrics/export/sink/connector/MetricsExportSinkConnector.java

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+package org.apache.rocket.connect.metrics.export.sink.connector;
+
+import io.openmessaging.KeyValue;
+import io.openmessaging.connector.api.component.task.Task;
+import io.openmessaging.connector.api.component.task.sink.SinkConnector;
+import java.util.ArrayList;
+import java.util.List;
+import org.apache.rocket.connect.metrics.export.sink.util.ServiceProvicerUtil;
+
+public class MetricsExportSinkConnector extends SinkConnector {
+    private KeyValue config;
+
+    private List<MetricsExporter> metricsExporters;
+    {
+        metricsExporters = ServiceProvicerUtil.getMetricsExporterServices();
+    }
+
+    @Override public List<KeyValue> taskConfigs(int maxTasks) {
+        List<KeyValue> configs = new ArrayList<>();
+        configs.add(config);
+        return configs;
+    }
+
+    @Override public Class<? extends Task> taskClass() {
+        return MetricsExportSinkTask.class;
+    }
+
+    @Override public void start(KeyValue config) {
+        this.config = config;
+    }
+
+    @Override public void stop() {
+        this.config = null;
+    }
+
+    @Override public void validate(KeyValue config) {
+        for (MetricsExporter exporter: metricsExporters) {
+            exporter.validate(config);
+        }
+    }
+}

connectors/rocketmq-connect-metrics-exporter/src/main/java/org/apache/rocket/connect/metrics/export/sink/connector/MetricsExportSinkTask.java

@@ -0,0 +1,37 @@
+package org.apache.rocket.connect.metrics.export.sink.connector;
+
+import io.openmessaging.KeyValue;
+import io.openmessaging.connector.api.component.task.sink.SinkTask;
+import io.openmessaging.connector.api.component.task.sink.SinkTaskContext;
+import io.openmessaging.connector.api.data.ConnectRecord;
+import io.openmessaging.connector.api.errors.ConnectException;
+import java.util.List;
+import org.apache.rocket.connect.metrics.export.sink.util.ServiceProvicerUtil;
+
+
+public class MetricsExportSinkTask extends SinkTask {
+    private List<MetricsExporter> metricsExporters;
+
+    @Override public void put(List<ConnectRecord> sinkRecords) throws ConnectException {
+        for (MetricsExporter exporter : metricsExporters) {
+            exporter.export(sinkRecords);
+        }
+    }
+
+    @Override public void start(KeyValue config) {
+        for (MetricsExporter exporter : metricsExporters) {
+            exporter.start(config);
+        }
+    }
+
+    @Override public void stop() {
+        for (MetricsExporter exporter : metricsExporters) {
+            exporter.stop();
+        }
+    }
+
+    @Override public void init(SinkTaskContext sinkTaskContext) {
+        super.init(sinkTaskContext);
+        metricsExporters = ServiceProvicerUtil.getMetricsExporterServices();
+    }
+}

connectors/rocketmq-connect-metrics-exporter/src/main/java/org/apache/rocket/connect/metrics/export/sink/connector/MetricsExporter.java

@@ -0,0 +1,16 @@
+package org.apache.rocket.connect.metrics.export.sink.connector;
+
+import io.openmessaging.KeyValue;
+import io.openmessaging.connector.api.data.ConnectRecord;
+import java.util.List;
+
+public interface MetricsExporter {
+    void export(List<ConnectRecord> sinkRecords);
+
+    void validate(KeyValue config);
+
+    void start(KeyValue config);
+
+    void stop();
+
+}

connectors/rocketmq-connect-metrics-exporter/src/main/java/org/apache/rocket/connect/metrics/export/sink/util/ServiceProvicerUtil.java

@@ -0,0 +1,23 @@
+package org.apache.rocket.connect.metrics.export.sink.util;
+
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.List;
+import java.util.ServiceLoader;
+import org.apache.rocket.connect.metrics.export.sink.connector.MetricsExporter;
+
+/**
+ * @author: ming
+ */
+public class ServiceProvicerUtil {
+
+    public static List<MetricsExporter> getMetricsExporterServices(){
+        List<MetricsExporter> metricsExporterList = new ArrayList<>();
+        ServiceLoader<MetricsExporter> metricsExporters = ServiceLoader.load(MetricsExporter.class);
+        Iterator<MetricsExporter> iterator = metricsExporters.iterator();
+        while (iterator.hasNext()){
+            metricsExporterList.add(iterator.next());
+        }
+        return metricsExporterList;
+    }
+}