Allow setting numeric config variables in config update endpoint

[whummer]

Motivation

One of the Chaos Engineering features we want to enable in the Web app with @webdev51 is setting the KINESIS_ERROR_PROBABILITY/DYNAMODB_ERROR_PROBABILITY config variables, to simulate rate limiting for Kinesis/DynamoDB.

This can be enabled by asking the user to enable ENABLE_CONFIG_UPDATES=1 on LS startup (with the caveats / security implications that come with it, and which we have also documented in our docs), and then using the config update endpoint.

However, currently updating the value to ENABLE_CONFIG_UPDATES=1 is not fully working, as the service providers expect those values to be numeric, whereas the config update listener sets them as string. It seems reasonable to check if config values are numeric, and then convert them to float (the other approach would be to fix the logic in the provider, to be able to handle both float and str values).

Changes

• add is_number(..) check to config update, to automatically convert numeric strings to numbers

[alexrashed]

The change looks good!
I just feel like this could be somewhat of a rabbit hole without a standardized way of handling things (is the config responsible of the parsing or the providers?). However, the config update is a bit brittle, but somewhat safe if we - as the ones who know its limitations - are using it. 😄

[bentsku]

Could you maybe add a quick test here? tests.integration.test_config_endpoint.test_config_endpoint

I think the change is rather small and innocuous, but it'd be nice to validate the behaviour.

[coveralls]

coverage: 82.532% (-0.009%) from 82.541%
when pulling fdecb8f on config-update-number
into 469febb on master.

[bentsku]

thanks a lot for adding the test, LGTM! 👍

[bentsku]

good catch!

[github-actions]

LocalStack Community integration with Pro

       2 files         2 suites   1h 6m 37s ⏱️
2 327 tests 1 750 ✔️ 577 💤 0 ❌
2 328 runs  1 750 ✔️ 578 💤 0 ❌

Results for commit fdecb8f.