Maven构建不使用grpc-java生成代码。

Question

我试图用Java、Maven和Intellij为gRPC应用程序生成代码。

我遵循grpc https://github.com/grpc/grpc-java/blob/master/README.md的文档，但是当我构建这个项目时，没有生成任何代码。

这是我的pom.xml文件：

<?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.nolapps</groupId>
    <artifactId>grpc-simpleapp</artifactId>
    <version>1.0-SNAPSHOT</version>

<dependencies>
    <dependency>
        <groupId>io.grpc</groupId>
        <artifactId>grpc-netty-shaded</artifactId>
        <version>1.35.0</version>
    </dependency>
    <dependency>
        <groupId>io.grpc</groupId>
        <artifactId>grpc-protobuf</artifactId>
        <version>1.35.0</version>
    </dependency>
    <dependency>
        <groupId>io.grpc</groupId>
        <artifactId>grpc-stub</artifactId>
        <version>1.35.0</version>
    </dependency>
    <dependency> <!-- necessary for Java 9+ -->
        <groupId>org.apache.tomcat</groupId>
        <artifactId>annotations-api</artifactId>
        <version>6.0.53</version>
        <scope>provided</scope>
    </dependency>
</dependencies>
    <build>
        <extensions>
            <extension>
                <groupId>kr.motd.maven</groupId>
                <artifactId>os-maven-plugin</artifactId>
                <version>1.6.2</version>
            </extension>
        </extensions>
        <plugins>
            <plugin>
                <groupId>org.xolstice.maven.plugins</groupId>
                <artifactId>protobuf-maven-plugin</artifactId>
                <version>0.6.1</version>
                <configuration>
                    <protocArtifact>com.google.protobuf:protoc:3.12.0:exe:${os.detected.classifier}</protocArtifact>
                    <pluginId>grpc-java</pluginId>
                    <pluginArtifact>io.grpc:protoc-gen-grpc-java:1.35.0:exe:${os.detected.classifier}</pluginArtifact>
                </configuration>
                <executions>
                    <execution>
                        <goals>
                            <goal>compile</goal>
                            <goal>compile-custom</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>
</project>

我的proto文件位于src/main/proto (messages.proto)中。

syntax = "proto3";

option java_package="grpc.messages";

message Employee {
    int32 id = 1;
    int32 badgeNumber = 2;
    string firstName = 3;
    string lastName = 4;
    float vacationAccrualRate = 5;
    float vacationAccrued = 6;
}

message GetAllRequest {}

message GetByBadgeNumberRequest {
    int32 badgeNumber = 1;
}

message EmployeeRequest {
    Employee employee = 1;
}

message EmployeeResponse {
    Employee employee = 1;
}

message AddPhotoRequest {
    bytes data = 1;
}

message AddPhotoResponse {
    bool isOk = 1;
}

service EmployeeService {
    rpc GetByBadgeNumber (GetByBadgeNumberRequest) returns (EmployeeResponse);
    rpc GetAll (GetAllRequest) returns (stream EmployeeResponse);
    rpc Save (EmployeeRequest) returns (EmployeeResponse);
    rpc SaveAll (EmployeeRequest) returns (stream EmployeeResponse);
    rpc AddPhoto (AddPhotoRequest) returns (AddPhotoResponse);
}

要构建该项目(来自Intelij)，我转到: build -> Build project。但什么都没发生。

我的问题:知道为什么没有生成我的代码吗？

Answer 1

通常Maven将生成代码并将其置于target/generated-source/protubf下

为了构建代码，需要发出以下命令：

 $ mvn clean install

在IntelliJ中，您需要编辑run的配置( RUN -> Edit Configuration )

还可以通过向插件中添加以下配置来定义maven中的protobuf插件的输出目录

        <plugin>
            <groupId>org.xolstice.maven.plugins</groupId>
            <artifactId>protobuf-maven-plugin</artifactId>
            <version>0.6.1</version>
            <configuration>
                <protocArtifact>com.google.protobuf:protoc:3.21.7:exe:${os.detected.classifier}</protocArtifact>
                <pluginId>grpc-java</pluginId>
                <pluginArtifact>io.grpc:protoc-gen-grpc-java:1.51.0:exe:${os.detected.classifier}</pluginArtifact>
                <outputBaseDirectory>src/main/java/</outputBaseDirectory>
                <outputDirectory>src/main/java/</outputDirectory>
                <clearOutputDirectory>false</clearOutputDirectory>
            </configuration>
            <executions>
                <execution>
                    <goals>
                        <goal>compile</goal>
                        <goal>compile-custom</goal>
                    </goals>
                    <configuration>
                    </configuration>
                </execution>
            </executions>
        </plugin>

这将输出java目录下生成的文件，并创建proto文件中定义的包(示例中为grpc.messages )。