Initializing Expectations

To ensure expectations are available as soon as MockServer is started it is possible to use an expectation initializer, there are three options:

• initializer class loaded from the classpath to construct an array of expectations
• initializer JSON file loaded from the filesystem containing a serialised array of expectations
• maven plugin loaded from the classpath to add expectations using the MockServerClient

Note: all three options require the class or file to be available to the MockServer, i.e. in the local classpath or filesystem. To remotely initialise the MockServer a client is required to connect to the MockServer after it has started and submit one or more expectations.

Expectation Initializer Class

MockServer expectations can be initialized when the MockServer starts, using a class, by specified the initializationClass configuration property as described in the Configuration Properties page, for example:

java -Dmockserver.initializationClass="org.mockserver.server.initialize.ExpectationInitializerExample" -jar ~/Downloads/mockserver-netty-5.6.1-jar-with-dependencies.jar -serverPort 1080 -logLevel INFO

The class must implement the org.mockserver.server.initialize.ExpectationInitializer interface and have a default constructor with zero arguments, for example:

public class ExpectationInitializerExample implements ExpectationInitializer {
    @Override
    public Expectation[] initializeExpectations() {
        return new Expectation[]{
            new Expectation(
                request()
                    .withPath("/simpleFirst")
            )
                .thenRespond(
                response()
                    .withBody("some first response")
            ),
            new Expectation(
                request()
                    .withPath("/simpleSecond")
            )
                .thenRespond(
                response()
                    .withBody("some second response")
            )
        };
    }
}

Expectation Initializer JSON

MockServer expectations can be initialized when the MockServer starts, using a JSON file, by specified the initializationJsonPath configuration property as described in the Configuration Properties page, for example:

java -Dmockserver.initializationJsonPath="org/mockserver/server/initialize/initializerJson.json" -jar ~/Downloads/mockserver-netty-5.6.1-jar-with-dependencies.jar -serverPort 1080 -logLevel INFO

The JSON file can be loaded using a related or absolute path or can be loaded from the classpath.

The JSON file should contain an array of serialised expectations, for example:

[
  {
    "httpRequest": {
      "path": "/simpleFirst"
    },
    "httpResponse": {
      "body": "some first response"
    }
  },
  {
    "httpRequest": {
      "path": "/simpleSecond"
    },
    "httpResponse": {
      "body": "some second response"
    }
  }
]

Maven Plugin Expectation Initializer Class

If the MockServer is started using the Maven Plugin a initializationClass property can be specified to initialize expectations, when the MockServer starts.

Note: the plugin must be started during the process-test-classes to ensure that the initialization class has been compiled from either src/main/java or src/test/java locations. In addition the initializer can only be used with start and run goals, it will not work with the runForked goal as a JVM is forked with a separate classpath. (required: false, default: false)

The following section from a pom.xml shows how the Maven Plugin can be configured to specify an initializationClass:

<plugin>
    <groupId>org.mock-server</groupId>
    <artifactId>mockserver-maven-plugin</artifactId>
    <version>5.6.1</version>
    <configuration>
        <serverPort>1080</serverPort>
        <logLevel>DEBUG</logLevel>
        <initializationClass>org.mockserver.maven.ExampleInitializationClass</initializationClass>
    </configuration>
    <executions>
        <execution>
            <id>process-test-classes</id>
            <phase>process-test-classes</phase>
            <goals>
                <goal>start</goal>
            </goals>
        </execution>
        <execution>
            <id>verify</id>
            <phase>verify</phase>
            <goals>
                <goal>stop</goal>
            </goals>
        </execution>
    </executions>
</plugin>

The class must implement the org.mockserver.client.initialize.ExpectationInitializer interface and have a default constructor with zero arguments, for example:

public class ExampleInitializationClass implements ExpectationInitializer {

    @Override
    public void initializeExpectations(MockServerClient mockServerClient) {
        mockServerClient
                .when(
                        request()
                                .withPath("/simpleFirst")
                )
                .respond(
                        response()
                                .withBody("some first response")
                );
        mockServerClient
                .when(
                        request()
                                .withPath("/simpleSecond")
                )
                .respond(
                        response()
                                .withBody("some second response")
                );
    }
}