基于SpringBoot开发gRpc服务接口_@grpcservice

开发一个gRpc接口包括两部分 一是编写proto文件，借助插件生成编译后的文件。二是基于编译后的文件编写gRpc服务实现类和方法。

声明proto文件

下面示例创建一个 chainDismantleBillService.proto 文件

syntax = "proto3";
option java_package = "com.gRpc.demo.bill";
 
//声明gRpc服务名 关键词 service
service ChainBillService {
	//声明gRpc服务方法 关键词 rpc 参数包括入参和出参
    rpc queryBillDetail (billRequest) returns (queryBillDetailRes) {};
}
//声明gRpc方法中用到的参数结构 类型包括 uint64 uint32 string double 等
message billRequest {
    uint64 groupID = 2;
    uint32 billStatus = 3;
    string auditBy = 4;
    string billIDs = 5;
}
message queryDismantleBillListReq {
    CommRequest commRequest = 1;
    uint64 groupID = 2;
    string allotIDs = 3;
    uint32 pageNo = 10;
    uint32 pageSize = 11;
    string auditBy = 12;
    uint64 demandID = 13;
    string goodsIDs = 14;
    string supplierIDs = 15;
    string billType = 16;
}
message queryBillDetailRes {
    string code = 1;
    string msg = 2;
    bool success = 3;
	//复合结构 声明Data类型并在queryBillDetailRes结构下引用该数据类型
    message Data {
        ChainBill bill = 1;
		//集合类型 关键字 repeated
        repeated ChainBillDetail details = 2;
    }
    Data data = 4;
}
 
message ChainBill {
    uint64 billID = 1 ;
    uint64 groupID = 2 ;/*集团ID*/
    uint32 demandType = 3 ;
    uint64 demandID = 4 ;
    string demandName = 5 ;
    string billNo = 6 ;
    uint32 billType = 7 ;
    uint32 billStatus = 8 ;
    uint64 billDate = 9 ;
}
message ChainBillDetail{
    uint64 billDetailID = 1;/*billDetailID*/
    uint64 groupID = 2;/*集团ID*/
    string billNo = 6;/*订单单号*/
    uint32 billType = 7;/*订单类型,（ 0 订货单、1 退货单、2 采购申请单、3 采购订单、4 到货单、5 验货单、6 结算单、7 付款单）*/
    string goodsName = 22;/*物品名称*/
    double goodsNum = 26;/*物品数量*/
    double taxPrice   = 27;/*含税单价*/
    double taxAmount  = 28;/*含税金额*/
    string orgCode   = 52;/*订单发起组织的编码*/
    uint32 isCreateBill = 53;/*是否生成订货单*/
    double rateValue  = 54;/*供应商税率*/
    double assistUnitper = 55;/*辅助单位转换率*/
    string actionBy = 56;/*操作人字段*/
}

在pom文件中添加proto编译插件

 <build>
        <plugins>
            <!-- protobuf 生成bean 的插件 -->
            <plugin>
                <groupId>org.xolstice.maven.plugins</groupId>
                <artifactId>protobuf-maven-plugin</artifactId>
                <version>0.5.0</version>
                <extensions>true</extensions>
                <configuration>
                    <protocArtifact>com.google.protobuf:protoc:3.4.0:exe:${os.detected.classifier}</protocArtifact>
                    <clearOutputDirectory>false</clearOutputDirectory>
                    <outputDirectory>src/main/java</outputDirectory><!-- 指定编译文件生成的目录位置 -->
                    <pluginId>grpc-java</pluginId>
                    <pluginArtifact>io.grpc:protoc-gen-grpc-java:1.8.0:exe:${os.detected.classifier}</pluginArtifact>
                </configuration>
                <executions>
                    <execution>
                        <goals>
                            <goal>compile</goal>
                            <goal>compile-custom</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>

执行maven的install命令或单独执行maven中的Plugins中的插件，生成编译后的java文件。

编译后会生成两个文件，位置位于上面proto文件中option java_package指定的目录下。

编写gRpc服务实现类

新建服务实现类，继承上面生成的与proto同名的类的的内部抽象类（以ImplBase结尾），并给服务实现类添加@GRpcService注解，指定grpcServiceOuterClass属性为上面生成的与proto同名的类。

@GRpcService(grpcServiceOuterClass = ChainDismantleBillServiceGrpc.class)
public class ChainDismantleBillGrpcService extends ChainDismantleBillServiceGrpc.ChainDismantleBillServiceImplBase {
    @Autowired
    private ChainDismantleBillService chainDismantleBillService;
	
	//重写proto文件中同名的方法
	@Override
    public void queryDismantleBillDetail(ChainDismantleBillServiceOuterClass.billRequest request, StreamObserver<ChainDismantleBillServiceOuterClass.queryBillDetailRes> responseObserver) {
        ChainDismantleBillServiceOuterClass.queryDismantleBillDetailRes.Builder response = ChainDismantleBillServiceOuterClass.queryDismantleBillDetailRes.newBuilder();
        try {
            Long groupID = request.getGroupID();
            String billIDs = request.getBillIDs();
            ChainDismantleBillServiceOuterClass.queryDismantleBillDetailRes.Data.Builder  data = chainDismantleBillService.queryDismantleBillDetail(groupID,billIDs);
            response.setData(data);
            response.setCode(BasicErrorCode.SUCCESS.getCode()).setSuccess(BasicErrorCode.SUCCESS.isSuccess()).setMsg(BasicErrorCode.SUCCESS.getMessage());
        } catch (Exception e) {
            GlobalGrpcException.handlerException(e, request, request.getCommRequest(), responseObserver);
            return;
        }
		//注意gRpc返回值的赋值方式 把结果赋值给responseObserver
        responseObserver.onNext(response.build());
        responseObserver.onCompleted();
    }
}