What is the problem?

After upgrading from 2.0.0 to 2.1.0 we are no longer able to deploy, receiving:
TTL value cannot be smaller than 1 second and larger than 3600 seconds. (Service: AWSAppSync; Status Code: 400; Error Code: BadRequestException

This seems to be caused by #17815, that introduces cachingConfig to appsync resolvers.

Despite the Cloudformation documentation specifying both the CachingConfig and its two Properties CachingKeys & Ttl as optional, our tests show that when CachingConfig is set, Ttl must be as well.

Current state of v2.1.0:
Not specifying any cachingConfig fails.
Specifying a cachingConfig including only cachingKeys fails.
Specifying a cachingConfig including only ttl succeeds.
Specifying a cachingConfig with both cachingKeys and ttl succeeds.

So it seems like ttl cannot be optional, and we need to check if cachingConfig is passed before adding it to the cfnResolver at line 117 in resolver.ts

@kylevillegas93 Are you able to look into this? I'm happy to help, but also quite busy until next year, and it would be nice to have a fix before then.

Reproduction Steps

Deploy a stack with any appsync resolver, without specifying cachingConfig.

What did you expect to happen?

Deployment to succeed without any errors.

What actually happened?

Deployment fails with: TTL value cannot be smaller than 1 second and larger than 3600 seconds. (Service: AWSAppSync; Status Code: 400; Error Code: BadRequestException

CDK CLI Version

2.1.0

Framework Version

2.1.0

Node.js Version

14.18.2

OS

macOS 11.6.1

Language

Typescript

Language Version

No response

Other information

No response