Unable to send empty map value in request

[j0hnsmith]

Version of AWS SDK for Go?

v0.9.0

Version of Go (go version)?

all

What issue did you see?

In the api lex api, sending an empty map for the key sessionAttributes: {} deletes existing session attributes however omitting the key keeps the existing ones. It's not possible to delete attributes as no distinction, in the current implementation, is made between a nil map and an empty one.

aws-sdk-go-v2/service/lexruntimeservice/api_op_PostText.go

Line 132 in 801e5ee

if len(s.SessionAttributes) > 0 {

Steps to reproduce

• make first request with session attributes
• response includes session attributes as expected
• make second request with empty session attributes map
• response includes session attributes as set by first request, they should have been removed

https://docs.aws.amazon.com/lex/latest/dg/context-mgmt.html

[jasdel]

Thanks for reporting this issue @j0hnsmith. This looks to be a issue with the SDK's marshaling code generator not distinguishing between empty and nil. This behavior is probably similar with slices as well as maps.

We need to investigate this behavior, I would think sending empty list/map would be the correct behavior when empty.

[jasdel]

The code generation that drives the len(v) > 0 check is in private/model/api/shape_marshal.go

[jasdel]

Thanks for reporting this issue @j0hnsmith. We've merged in a fix that addresses this bug. You should now be able to send empty maps and lists with the V2 SDK.

[j0hnsmith]

Great work and so quick, thanks, I'll try it out tomorrow.