Writing Integration Tests

To create a new integration test, follow these steps:

1. Prepare IT Resources Structure

Create the connector-specific resources folder under src/it/resources/ e.g., src/it/resources/Linux/.

Under this folder, create the following subfolders:

Important: You must name the connector-specific resources folder exactly as the connector identifier configured in the metricshub.yaml (e.g., for +Linux in metricshub.yaml create src/it/resources/Linux/).

2. Prepare the emulation Folder

metricsHub babbage -t linux --ssh-username userName --ssh-password userPassword -c +Linux --record

snmpcli dev-01 --walk 1.3.6.1 --community public --version v1 --port 161 --timeout 60 > 1.3.6.1.walk

3. Prepare the config Folder

Add a minimal metricshub.yaml config under src/it/resources/<MyConnectorId>/config (e.g src/it/resources/Linux/config). Example for Linux:

otel:
  otel.exporter.otlp.metrics.protocol: noop
patchDirectory: src/main/connector
resources:
  localhost:
    attributes:
      host.name: localhost
      host.type: linux
    protocols:
      ssh:
        username: user
        password: password
        timeout: 300
    connectors: ["+Linux"]

Important: Make sure to set the patch directory to src/main/connector so that the connector code is used during the IT.

4. Prepare the expected Folder

Create the expected.json file under src/it/resources/<MyConnectorId>/expected/, to generate it follow these steps:

• Create a new unit test to capture the expected JSON using the saveTelemetryManagerJson method provided by the EmulationITBase class, for example:

class ConnectorReplayIT {

	@Test
	void testCapture() throws Exception {
		new EmulationITBase("MyConnector")
			.withServerRecordData()
			.executeStrategies()
			.saveTelemetryManagerJson(Paths.get("target", "expected.json"))
	}
}

• Run the IT via maven:

mvn clean verify -Dtest=ConnectorReplayIT#testCapture

• Copy the generated expected.json from target/expected.json to the connector’s src/it/resources/<MyConnectorId>/expected folder.

• Replace all the occurrences of the host name with localhost in the expected.json file.

Note: When you update the connector code, it is recommended to not regenerate the expected.json file unless the expected has fully changed.

5. Add the Connector to the Parametrized IT

In ConnectorReplayIT.java, add the connector name to the @ValueSource annotation:

class ConnectorReplayIT {

	@ParameterizedTest
	@ValueSource(strings = {
		"WinStorageSpaces",
		"MIB2",
		"Lmsensors",
		"Linux",
		"MySql",
		"WbemGenDiskNT",
		"SmartMonLinux",
        "MIB2Switch",
        "MyConnectorId"  // <--- Add your connector here
	})
	void testConnectorReplay(String connectorName) throws Exception {
		new EmulationITBase(connectorName)
			.withServerRecordData()
			.executeStrategies()
			.verifyExpected(connectorName + "/expected/expected.json");
	}
}