Use string-safe encoding for partition keys

[jmccance]

Pull Request Template

Description

When using the key as the partition key in the database producer backend, encode as ~JSON~ YAML to avoid ActiveRecord quoting issues.

Fixes #95

Type of change

Please delete options that are not relevant.

• [X] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)
• [ ] This change requires a documentation update

How Has This Been Tested?

Please describe the tests that you ran to verify your changes. Provide instructions so we can reproduce. Please also list any relevant details for your test configuration

• [X] Added a unit test to verify that when Hash keys are used they are encoded as expected

Checklist:

• [X] My code follows the style guidelines of this project
• [X] I have performed a self-review of my own code
• [X] I have commented my code, particularly in hard-to-understand areas
• [X] I have made corresponding changes to the documentation
• [X] My changes generate no new warnings
• [X] I have added tests that prove my fix is effective or that my feature works
• [X] New and existing unit tests pass locally with my changes
• [X] Any dependent changes have been merged and published in downstream modules

[jmccance]

@dorner In #95 we talked about using to_yaml. I went with to_json here, thinking that it's (1) easier to read in a single line and (2) how Avro objects are typically presented for human consumption. If you'd prefer we stick to_yaml, let me know and I'll update.

[dorner]

Hey @jmccance! I'd actually prefer that we go back to to_yaml, because otherwise it's going to introduce a breaking change - e.g. if the partition key for ID 1 used to be a hash of "string A" and now it's a hash of "string B", that will evaluate to a different partition and it'll break the partitioning schema when we update.

Thanks a bunch! 😄

[jmccance]

@dorner Totally reasonable. Updated to use to_yaml.

[dorner]

LGTM!

[dorner]

Version 1.8.3 has been released - thanks so much for the contribution!