Move registry creation to @BeforeEach in SampleTestRunner

[ttddyy]

Simplifies the meter and observation registries management in SampleTestRunner

• Add "create[Meter|Observation]Registry" protected methods
• Initialize registries in @beforeeach
• Remove the constructor that takes registries
• Each parameterized test creates a new registries
• Remove code to track used registries and @afterall to close them
• Remove TestConfigAccessor
• Preserve and restore observation handlers for each run (for the usage of global registries instead of creating every time)

[marcingrzejszczak]

LGTM however I'd like @violetagg to take a look at this branch (if possible 🙏 ) with what she has there in Reactor Netty.

[violetagg]

LGTM however I'd like @violetagg to take a look at this branch (if possible 🙏 ) with what she has there in Reactor Netty.

I'll check it

[violetagg]

@ttddyy @marcingrzejszczak Do we need to recreate the registry for every test?

In Reactor Netty we have

	@BeforeAll
	static void setUp() throws CertificateException {
		...

		registry = new SimpleMeterRegistry();
		Metrics.addRegistry(registry);

		...
	}

	@AfterAll
	static void tearDown() {
		Metrics.removeRegistry(registry);
		registry.clear();
		registry.close();
	}

Also the change is breaking change :)

/.../reactor-netty/reactor-netty-http/src/test/java/reactor/netty/http/observability/ObservabilitySmokeTest.java:64: error: no suitable constructor found for SampleTestRunner(SampleRunnerConfig,ObservationRegistry,MeterRegistry)
                super(SampleTestRunner.SampleRunnerConfig.builder().build(), OBSERVATION_REGISTRY, registry);

[marcingrzejszczak]

In Reactor Netty we have

So in your cae you would override the createMeterRegistry method where you will essentially do what you do in your setUp method

Also the change is breaking change :)

That is not possible because we typically do those just after the release ;) yeah... that's a breaking change

[violetagg]

LGTM ;)