com.github.balchua:gire-mock

GireMock

A gRPC mock server which utilizes WireMock for handling mock requests.

gireMock utilizes the excellent project from salesforce - jProtoc to generate code as part of protobuf maven plugin code gen and Wiremock to serve mock requests back to gRPC clients.

How to use gireMock

If you are using Maven, follow the instruction below.

• Add a dependency to gireMock

<dependency>
    <groupId>io.bal.tools.grpc</groupId>
    <artifactId>gire-mock</artifactId>
    <version>1.0-SNAPSHOT</version>
    <scope>compile</scope>
</dependency>

• if you are using protobuf-maven-plugin, add gireMock to the protoPlugin section of the protobuf-maven-plugin <execution><configuration> section.

Sample below.

<plugin>
    <groupId>org.xolstice.maven.plugins</groupId>
    <artifactId>protobuf-maven-plugin</artifactId>
    <version>0.5.0</version>
    <configuration>
        <protocArtifact>com.google.protobuf:protoc:3.3.0:exe:${os.detected.classifier}</protocArtifact>
        <pluginId>grpc-java</pluginId>
        <pluginArtifact>io.grpc:protoc-gen-grpc-java:1.6.1:exe:${os.detected.classifier}</pluginArtifact>
    </configuration>
    <executions>
        <execution>
            <goals>
                <goal>compile</goal>
                <goal>compile-custom</goal>
            </goals>
            <configuration>
                <protocPlugins>
                    <protocPlugin>
                        <id>java8</id>
                        <groupId>io.bal.tools.grpc</groupId>
                        <artifactId>gire-mock</artifactId>
                        <version>1.0-SNAPSHOT</version>
                        <mainClass>io.giremock.generator.mock.MockGenerator</mainClass>
                    </protocPlugin>
                </protocPlugins>
            </configuration>
        </execution>
    </executions>
</plugin>

Generated codes

All classes generated will have these classes:

• <GRPC service name>Mockery.class
• <GRPC service name>Mock.class

For example the following gRPC service definition

service PersonManagement {

    rpc GetPersonById (PersonById) returns (Person) {
    }

    rpc randomNames (google.protobuf.Empty) returns (Person) {
    }

    rpc whatsTheNameInTheFile (google.protobuf.Empty) returns (FileContent) {

    }
}

The generated classes will be:

PersonManagementMockery.PersonManagementMock

Starting the mock server

Since all the generated codes are part of your project, you can easily start your gRPC server like below.

Arguments to the Mock Services are Wiremock host and port.

Server server = ServerBuilder.forPort(port).
                addService(new PersonManagementMockery.PersonManagementMock("localhost",5501)).
                build();
server.start();

. . . 
       
server.awaitTermination();

Start your WireMock instance.

java -jar wiremock-standalone-2.20.0.jar --port 5501

Specifying WireMock mocks

If you have Grpc method (GetPersonById)

You should define your request.url to be /getPersonById

The response body must adhere to the Message returned by the method.

{
    "request": {
        "method": "POST",
        "url": "/getPersonById", 
        "bodyPatterns" : [ {
          "equalToJson" : "{ \"id\": 4 }"
        } ]
    },
    "response": {
        "status": 200,
        "body": "{ 'id' : '123', 'firstName' : 'ultimate', 'lastName' : 'warrior', 'description' : 'Wrestler'}"
       
    }
}

Example:

See grpcdomain project repo.

Limitations:

• Supports only unary calls.