feat(v2): Validation failures return 400s

[skal111]

api gateway events validation will be catched and returned as a 400 error

#1298

Description of changes:

ValidationException for events of type APIGateway are catched and transformed into a valid response (status 400).

Checklist

• Meet tenets criteria
• Update tests
• Update docs
• PR title follows conventional commit semantics

Breaking change checklist

RFC issue #:

• Migration process documented
• Implement warnings (if it can live side by side)

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[jeromevdl]

See above comments.

[jeromevdl]

Additional point that we completely forgot: it would be great to make the @Validation annotation compatible with the batch module (SQS, Kinesis), i.e. if one message is wrong do not fail the whole batch but add the message to the partial failure list.

my idea:

• browse the list of messages and validate each one (here),
• log a warn for each invalid message
• remove the ones that are not good (no need to pass them to the rest of the batch processing),
• add them to the list of failure (example)

@scottgerring what do you think?

[scottgerring]

Additional point that we completely forgot: it would be great to make the @Validation annotation compatible with the batch module (SQS, Kinesis), i.e. if one message is wrong do not fail the whole batch but add the message to the partial failure list.

This is a great idea - I think PT should aspire to "magically do what you'd expect" when you combine modules. We'd need to pay special attention to the coupling between the modules - explicitly maven coupling between batch<->validation is IMHO a non-starter. Perhaps we could pull validation exceptions into their own package, or something 🤷 - i've not thought about this in depth, but I think how this coupling would work will be decisive here.

@jeromevdl pragmatically we could also treat this integration in a subsequent PR. WDYT?

[jeromevdl]

I agree we could do that in another PR: #1496

Regarding the coupling, there should not be any dependency between the 2 modules. And I think there won't be any.

1. We can keep the validation code as today (almost) but rather than throwing an exception, do just like @skal111 did for API GW, ie. creating an SQSBatchResponse / StreamsEventResponse and put the messages in error in the partial error.

2. Then the handler is called with all the remaining messages (or directly return if no message is valid), and here the batch module will work.

3. In the end the validation module completes the SQSBatchResponse / StreamsEventResponse returned by the handler (batch module) with the validation failure from 1.

Finger in the nose ?!

[jeromevdl]

last couple of things + rebase v2 and we should be good

[scottgerring]

@jeromevdl let's merge this when the build succeeds

[scottgerring]

@skal111 it looks like you are using Java11+ collection helpers - if you can port that back so the java 8 build succeeds we can merge this!

[jeromevdl]

Suggested change

	APIGatewayV2HTTPEvent event = new APIGatewayV2HTTPEvent();
	event.setBody("{" +
	" \"id\": 1," +
	" \"name\": \"Lampshade\"" +
	"}");
	event.setHeaders(Map.of("header1", "value1"));
	APIGatewayV2HTTPResponse response = handler.handleRequest(event, context);
	assertThat(response.getBody()).isNotBlank();
	assertThat(response.getStatusCode()).isEqualTo(400);
	assertThat(response.getHeaders()).isEmpty();
	assertThat(response.getMultiValueHeaders()).isEmpty();
	APIGatewayV2HTTPEvent event = new APIGatewayV2HTTPEvent();
	event.setBody("{" +
	" \"id\": 1," +
	" \"name\": \"Lampshade\"" +
	"}");
	event.setHeaders(Map.of("header1", "value1"));
	APIGatewayV2HTTPResponse response = handler.handleRequest(event, context);
	assertThat(response.getBody()).isNotBlank();
	assertThat(response.getStatusCode()).isEqualTo(400);
	assertThat(response.getHeaders()).isEmpty();
	assertThat(response.getMultiValueHeaders()).isEmpty();

[jeromevdl]

LGTM, thank you @skal111

[sonarqubecloud]

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0 Bugs
0 Vulnerabilities
0 Security Hotspots
3 Code Smells

No Coverage information
0.0% Duplication

[jeromevdl]

I've tested the e2e locally, it's ok!