Helidon MP/Maven：子项目合并共享库自定义配置源路径问题

方案一：使用maven-shade-plugin的ServicesResourceTransformer #

maven-shade-plugin专门提供了ServicesResourceTransformer来处理META-INF/services文件的合并，这比通用的AppendingTransformer更精准。修改子项目的pom.xml配置：

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-shade-plugin</artifactId>
    <version>3.5.3</version> <!-- 使用最新稳定版 -->
    <executions>
        <execution>
            <phase>package</phase>
            <goals>
                <goal>shade</goal>
            </goals>
            <configuration>
                <transformers>
                    <!-- 专门处理services文件合并 -->
                    <transformer implementation="org.apache.maven.plugins.shade.resource.ServicesResourceTransformer"/>
                    <!-- 按需配置主类，不需要可删除 -->
                    <transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
                        <mainClass>your.main.class.path</mainClass>
                    </transformer>
                </transformers>
            </configuration>
        </execution>
    </executions>
</plugin>

执行mvn clean package后，target目录下的META-INF/services/org.eclipse.microprofile.config.spi.ConfigSource会自动合并共享库和子项目的两个类路径。

方案二：使用maven-resources-plugin手动合并 #

如果不想用shade插件，可以结合maven-dependency-plugin和maven-resources-plugin手动实现合并：

1. 先提取共享库中的services文件到临时目录：

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-dependency-plugin</artifactId>
    <version>3.6.1</version>
    <executions>
        <execution>
            <id>extract-services</id>
            <phase>process-resources</phase>
            <goals>
                <goal>unpack</goal>
            </goals>
            <configuration>
                <artifactItems>
                    <artifactItem>
                        <groupId>你的共享库groupId</groupId>
                        <artifactId>你的共享库artifactId</artifactId>
                        <version>共享库版本号</version>
                        <includes>META-INF/services/org.eclipse.microprofile.config.spi.ConfigSource</includes>
                        <outputDirectory>${project.build.directory}/tmp-services</outputDirectory>
                    </artifactItem>
                </artifactItems>
            </configuration>
        </execution>
    </executions>
</plugin>

2. 合并子项目与共享库的services文件：

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-resources-plugin</artifactId>
    <version>3.3.1</version>
    <executions>
        <execution>
            <id>merge-services</id>
            <phase>process-resources</phase>
            <goals>
                <goal>copy-resources</goal>
            </goals>
            <configuration>
                <outputDirectory>${project.build.outputDirectory}/META-INF/services</outputDirectory>
                <resources>
                    <resource>
                        <directory>${project.build.directory}/tmp-services/META-INF/services</directory>
                    </resource>
                    <resource>
                        <directory>src/main/resources/META-INF/services</directory>
                        <filtering>false</filtering>
                    </resource>
                </resources>
                <overwrite>false</overwrite> <!-- 不覆盖，实现内容追加 -->
            </configuration>
        </execution>
    </executions>
</plugin>

该方式会先复制共享库的services内容，再将子项目的内容追加到目标文件中。

注意事项 #

• 确保子项目的META-INF/services文件放在src/main/resources目录下，避免放在src/test/resources导致打包时被忽略。
• 使用shade插件时，默认会覆盖原jar包，若想保留原jar可添加<shadedArtifactAttached>true</shadedArtifactAttached>配置，生成单独的shaded jar。

内容的提问来源于stack exchange，提问作者swing1234