broker

TestApp::broker addresses one broker of the app by its production type, for publishing to it and reading its records.

B is the type the app registered, so MemoryBroker and MemoryBroker<Retaining> are two different brokers. The BrokerHandle it returns publishes onto that broker with message(&v) and opens its records: subscriber(name) and published::<T>(name). A subscription name is local to its broker: the "orders" of one broker is not the "orders" of the other. broker panics when the app has no broker of type B or more than one; two brokers of one type are addressed by label with broker_named. In live mode the test's input reaches the broker through its connected form's default publish policy.

Example

Macros

examples/testing_driving.rs

#[tokio::test]
async fn each_broker_is_addressed_by_its_type() -> Result<(), Box<dyn Error>> {
    let tb = TestApp::start(app()).await?;
    tb.broker::<MemoryBroker<Retaining>>()
        .message(&Order { id: 7 })
        .publish()
        .await?;

    tb.broker::<MemoryBroker<Retaining>>()
        .subscriber("orders")
        .assert_called_once();
    tb.broker::<MemoryBroker>()
        .subscriber("orders")
        .assert_not_called();
    Ok(())
}

Manual

examples/manual/testing_driving.rs

#[tokio::test]
async fn each_broker_is_addressed_by_its_type() -> Result<(), Box<dyn Error>> {
    let tb = TestApp::start(app()).await?;
    tb.broker::<MemoryBroker<Retaining>>()
        .message(&Order { id: 7 })
        .publish()
        .await?;

    tb.broker::<MemoryBroker<Retaining>>()
        .subscriber("orders")
        .assert_called_once();
    tb.broker::<MemoryBroker>()
        .subscriber("orders")
        .assert_not_called();
    Ok(())
}