AppSync Merged API L2 construct

[jumic]

Description

This RFC proposes a new L2 construct to support AppSync Merged APIs. Merged APIs can be used to combine multiple AppSync source APIs into a single (merged) AppSync API.

Compared to the existing AppSync GraphqlApi, a merged API has different attributes. The schema attribute is mandatory for GraphQL APIs. It doesn't exist for merged APIs. So it's necessary to create a new construct to support Merged APIs.

I have also created a feature request for initial discussions on this topic: aws/aws-cdk#25960

Roles

Role	User
Proposed by	@jumic
Author(s)	@jumic
API Bar Raiser
Stakeholders

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Workflow

• Tracking issue created (label: status/proposed)
• API bar raiser assigned (ping us at #aws-cdk-rfcs if needed)
• Kick off meeting
• RFC pull request submitted (label: status/review)
• Community reach out (via Slack and/or Twitter)
• API signed-off (label api-approved applied to pull request)
• Final comments period (label: status/final-comments-period)
• Approved and merged (label: status/approved)
• Execution plan submitted (label: status/planning)
• Plan approved and merged (label: status/implementing)
• Implementation complete (label: status/done)

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Author is responsible to progress the RFC according to this checklist, and
apply the relevant labels to this issue so that the RFC table in README gets
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[rix0rrr]

We talked during the Office Hours, and we agreed that this change should be small enough that it doesn't need a full RFC.

We will deprecate the schema: ISchema in favor of a new field that will be typed as an enum-like class, to decide between a schema-based API or a merged API.

[jumic]

I implemented a solution without new L2 construct: aws/aws-cdk#26895
So let's close this RFC issue.
@rix0rrr Thanks for our help!

[mrgrain]

We went down a different route than this RFC had proposed.