AppSyncApi: support custom domain

[fwang]

References:

• https://aws.amazon.com/blogs/mobile/use-a-custom-domain-with-aws-appsync-amazon-cloudfront-and-amazon-route-53/
• https://theburningmonk.com/2020/09/how-to-set-up-custom-domain-names-for-appsync/

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Requests:

• Gerald https://serverless-stack.slack.com/archives/C01HQQVC8TH/p1637296836207300?thread_ts=1637284298.206900&cid=C01HQQVC8TH
• Mischa https://serverless-stack.slack.com/archives/C01HQQVC8TH/p1648541259207479

[sionelt]

Custom domain for AppSync was recently released. How to setup on the console: https://aws.amazon.com/blogs/mobile/introducing-custom-domain-names-for-aws-appsync-apis/. Hopefully cloudformation/AWS CDK support soon.

[fwang]

Thanks @sionelt! Yup, we have our eyes on CDK support for it :)
aws/aws-cdk#18040

[tomaszdudek7]

Not sure if it proves any useful but there's also a similar feature request for Serverless Framework (and its AppSync plugin) here: sid88in/serverless-appsync-plugin#454

[davideicardi]

Now that custom domain is supported inside CDK (aws/aws-cdk#19368) do you think it will be possible to use custom domain inside serverless stack? How?

UPDATE (March 24): as of today I think that CDK version with the PR merged is not yet pubblished, I think we need to wait for v2.18

[revmischa]

Custom domain support in CDK is released now - would love this feature in SST!

[fwang]

Released in v1.0.0-beta.21.