What is the server behavior for deserializing httpQueryParams when multiple values appear for the same key?

[david-perez]

The httpQueryParams trait can be applied to structure members that target a map of string, or a map of list/set of string.

When it targets a map of strings, what should a server implementation deserialize to when encountering multiple values for the same query key param? Should it pick the first value or the last one in the query string? The docs don't specify a behavior.

There are also no protocol tests.

[adamthom-amzn]

There's no defined behavior. The current server implementation is, I believe, as follows:

• for @httpQuery scalar members, the first value is taken
• for @httpQueryParams with scalar values, the last value is taken

[adamthom-amzn]

As we don't have a way to add protocol tests for SHOULDs yet (though this made us think we, uh, should), right now all I can offer is a documentation update.

[david-perez]

As we don't have a way to add protocol tests for SHOULDs yet

@adamthom-amzn What mechanism did you have in mind? I was thinking that having separate test suites under smithy-aws-protocol-tests/model/ for SHOULDs should suffice.

[adamthom-amzn]

As we don't have a way to add protocol tests for SHOULDs yet

@adamthom-amzn What mechanism did you have in mind? I was thinking that having separate test suites under smithy-aws-protocol-tests/model/ for SHOULDs should suffice.

I was thinking that we would have at least a flag for SHOULD tests, so code generators would have the option to try to make the tests run but not fail the build, if it could be managed. That way we could keep the tests grouped by functionality.