[Feature] Add dev-mode option to ignore or widen the 15 minute SigV4 clock skew window

[jgaul3]

Problem or use case

While trying to migrate to extenddb from dynalite, I encountered unit test failures in tests which froze time outside the SigV4 clock skew window. I believe this is due to validate_timestamp rejecting any request whose X-Amz-Date is more than 15 minutes from the server's clock (see crates/auth/src/sigv4/verify.rs:18).

Since there is no way to change or disable this check even in dev-mode, test suites that time travel can't be migrated properly. Mocking time is a fairly common requirement for unit testing and I'm sure others have encountered this issue.

This can be reproduced via:

docker run -d -p 127.0.0.1:18080:18080 \
  -e EXTENDDB__STORAGE__SQLITE__PATH=:memory: extenddb/extenddb-dev:0.1.11

import boto3, time_machine
db = boto3.client("dynamodb", endpoint_url="http://127.0.0.1:18080",
                              region_name="us-east-1",
                              aws_access_key_id="AKIAIOSFODNN7EXAMPLE",
                              aws_secret_access_key="wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY")
db.list_tables()  # ok
with time_machine.travel("2021-01-01"):
    db.list_tables()  # UnrecognizedClientException

Proposed solution

I would expect a dev-mode-only setting to widen or disable the skew window e.g. EXTENDDB_DEV_MAX_CLOCK_SKEW_SECS with a value which explicitly means "don't check." If this value is unset I would expect the default behavior.

Alternatives considered

Some of the tests which failed could be rewritten, but doing so for the sake of the emulator seems wrong.

DynamoDB API reference

N/A

Additional context

Thank you for your time and attention.

Checklist

• I have searched existing issues and the roadmap for duplicates
• I have described the use case, not just the desired implementation

[LeeroyHannigan]

Thanks for this @jgaul3 I'll take a look at it and improve the experience.