Add agent version in gRPC connection establish stage (#3205)

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 * Licensed to the Apache Software Foundation (ASF) under one or more

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 *     http://www.apache.org/licenses/LICENSE-2.0

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package org.apache.skywalking.apm.agent.core.remote;

import io.grpc.CallOptions;

import io.grpc.Channel;

import io.grpc.ClientCall;

import io.grpc.ClientInterceptor;

import io.grpc.ClientInterceptors;

import io.grpc.ForwardingClientCall;

import io.grpc.Metadata;

import io.grpc.MethodDescriptor;

import java.io.InputStream;

import java.net.URL;

import java.util.Enumeration;

import java.util.jar.Attributes;

import java.util.jar.JarFile;

import java.util.jar.Manifest;

import org.apache.skywalking.apm.agent.core.logging.api.ILog;

import org.apache.skywalking.apm.agent.core.logging.api.LogManager;

/**

 * Add agent version(Described in MANIFEST.MF) to the connection establish stage.

 *

 * @author wusheng

 */

public class AgentIDDecorator implements ChannelDecorator {

    private static final ILog logger = LogManager.getLogger(AgentIDDecorator.class);

    private static final Metadata.Key<String> AGENT_VERSION_HEAD_HEADER_NAME =

        Metadata.Key.of("Agent-Version", Metadata.ASCII_STRING_MARSHALLER);

    private String version = "UNKNOWN";

    public AgentIDDecorator() {

        try {

            Enumeration<URL> resources = AgentIDDecorator.class.getClassLoader().getResources(JarFile.MANIFEST_NAME);

            while (resources.hasMoreElements()) {

                URL url = resources.nextElement();

                InputStream is = url.openStream();

                if (is != null) {

                    Manifest manifest = new Manifest(is);

                    Attributes mainAttribs = manifest.getMainAttributes();

                    String projectName = mainAttribs.getValue("Implementation-Vendor-Id");

                    if (projectName != null) {

                        if (projectName.equals("org.apache.skywalking")) {

                            version = mainAttribs.getValue("Implementation-Version");

                        }

                    }

                }

            }

        } catch (Exception e) {

            logger.warn("Can't read version from MANIFEST.MF in the agent jar");

        }

    }

    @Override public Channel build(Channel channel) {

        return ClientInterceptors.intercept(channel, new ClientInterceptor() {

            @Override

            public <REQ, RESP> ClientCall<REQ, RESP> interceptCall(MethodDescriptor<REQ, RESP> method,

                CallOptions options, Channel channel) {

                return new ForwardingClientCall.SimpleForwardingClientCall<REQ, RESP>(channel.newCall(method, options)) {

                    @Override

                    public void start(Listener<RESP> responseListener, Metadata headers) {

                        headers.put(AGENT_VERSION_HEAD_HEADER_NAME, version);

                        super.start(responseListener, headers);

                    }

                };

            }

        });

    }

}

package org.apache.skywalking.apm.agent.core.remote;

import io.grpc.*;

import java.util.*;

import java.util.concurrent.*;

import org.apache.skywalking.apm.agent.core.boot.*;

import io.grpc.Channel;

import io.grpc.Status;

import io.grpc.StatusRuntimeException;

import java.util.Arrays;

import java.util.Collections;

import java.util.LinkedList;

import java.util.List;

import java.util.Random;

import java.util.concurrent.Executors;

import java.util.concurrent.ScheduledFuture;

import java.util.concurrent.TimeUnit;

import org.apache.skywalking.apm.agent.core.boot.BootService;

import org.apache.skywalking.apm.agent.core.boot.DefaultImplementor;

import org.apache.skywalking.apm.agent.core.boot.DefaultNamedThreadFactory;

import org.apache.skywalking.apm.agent.core.conf.Config;

import org.apache.skywalking.apm.agent.core.logging.api.*;

import org.apache.skywalking.apm.agent.core.logging.api.ILog;

import org.apache.skywalking.apm.agent.core.logging.api.LogManager;

import org.apache.skywalking.apm.util.RunnableWithExceptionProtection;

/**

                        managedChannel = GRPCChannel.newBuilder(ipAndPort[0], Integer.parseInt(ipAndPort[1]))

                            .addManagedChannelBuilder(new StandardChannelBuilder())

                            .addManagedChannelBuilder(new TLSChannelBuilder())

                            .addChannelDecorator(new AgentIDDecorator())

                            .addChannelDecorator(new AuthenticationDecorator())

                            .build();