skywalking-java/docs/en/guides/How-to-build.md

How to build project

This document helps people to compile and build the project in your maven and set your IDE.

Build Project

Because we are using Git submodule, we recommend don't use GitHub tag or release page to download source codes for compiling.

Build from GitHub

1. Prepare git, JDK8 and maven3
2. git clone https://github.com/apache/incubator-skywalking.git
3. cd incubator-skywalking/
4. Switch to the tag by using git checkout [tagname] (Optional, switch if want to build a release from source codes)
5. git submodule init
6. git submodule update
7. Run ./mvnw clean package -DskipTests
8. All packages are in /dist (.tar.gz for Linux and .zip for Windows).

Build from Apache source code release

• What is Apache source code release?

For each official Apache release, there is a complete and independent source code tar, which is including all source codes. You could download it from SkyWalking Apache download page. No git related stuff required when compiling this. Just follow these steps.

1. Prepare JDK8 and maven3
2. Run ./mvnw clean package -DskipTests
3. All packages are in /dist.(.tar.gz for Linux and .zip for Windows).

Advanced compile

SkyWalking is a complex maven project, including many modules, which could cause long compiling time. If you just want to recompile part of the project, you have following options

• Compile agent and package

./mvnw package -Pagent,dist

• Compile backend and package

./mvnw package -Pbackend,dist

• Compile UI and package

./mvnw package -Pui,dist

Setup your IntelliJ IDEA

1. Import the project as a maven project
2. Run ./mvnw compile -Dmaven.test.skip=true to compile project and generate source codes. Because we use gRPC and protobuf.
3. Set Generated Source Codes folders.
   • grpc-java and java folders in apm-protocol/apm-network/target/generated-sources/protobuf
   • grpc-java and java folders in oap-server/server-core/target/generated-sources/protobuf
   • grpc-java and java folders in oap-server/server-receiver-plugin/skywalking-istio-telemetry-receiver-plugin/target/generated-sources/protobuf
   • grpc-java and java folders in oap-server/server-receiver-plugin/envoy-metrics-receiver-plugin/target/generated-sources/protobuf
   • grpc-java and java folders in oap-server/exporter/target/generated-sources/protobuf
   • antlr4 folder in oap-server/generate-tool-grammar/target/generated-sources
   • oal folder in oap-server/generated-analysis/target/generated-sources

Setup your Eclipse IDE

1. Import the project as a maven project
2. For supporting multiple source directories, you need to add the following configuration in incubator-skywalking/pom.xml file:

<plugin>
    <groupId>org.codehaus.mojo</groupId>
    <artifactId>build-helper-maven-plugin</artifactId>
    <version>1.8</version>
    <executions>
        <execution>
            <id>add-source</id>
            <phase>generate-sources</phase>
            <goals>
                <goal>add-source</goal>
            </goals>
            <configuration>
                <sources>
                    <source>src/java/main</source>
                    <source>apm-protocol/apm-network/target/generated-sources/protobuf</source>
                    <source>apm-collector/apm-collector-remote/collector-remote-grpc-provider/target/generated-sources/protobuf</source>
               </sources>
            </configuration>
        </execution>
    </executions>
</plugin>

3. Add the following configuration under to let eclipse's M2e plug-in supports execution's solution configuration

<pluginManagement>
    <plugins>
    <!--This plugin's configuration is used to store Eclipse m2e settings 
    only. It has no influence on the Maven build itself. -->
        <plugin>
            <groupId>org.eclipse.m2e</groupId>
            <artifactId>lifecycle-mapping</artifactId>
            <version>1.0.0</version>
            <configuration>
                <lifecycleMappingMetadata>
                    <pluginExecutions>
                        <pluginExecution>
                            <pluginExecutionFilter>
                                <groupId>org.codehaus.mojo</groupId>
                                <artifactId>build-helper-maven-plugin</artifactId>
                                <versionRange>[1.8,)</versionRange>
                                <goals>
                                    <goal>add-source</goal>
                                </goals>
                            </pluginExecutionFilter>
                        </pluginExecution>
                    </pluginExecutions>
                </lifecycleMappingMetadata>
            </configuration>
        </plugin>
    </plugins>
</pluginManagement>

4. Adding Google guava dependency to apm-collector-remote/collector-remote-grpc-provider/pom.xml files

<dependency>
   <groupId>com.google.guava</groupId>
   <artifactId>guava</artifactId>
   <version>24.0-jre</version>
</dependency>

5. Run ./mvnw compile -Dmaven.test.skip=true
6. Run maven update. Must remove the clean projects item before maven update(This will be clear the proto conversion Java file generated by the complie)
7. Run ./mvnw compile complie collector-remote-grpc-provider and apm-protocol
8. Refresh project