Cache: fix an issue where the cache key for mappings is wrong when mu…

[Alice-Lilith]

…ltiple mappings have the same name

Signed-off-by: AliceProxy [email protected]

Description

In Emissary-ingress 2.2 (and likely other 2.x releases) if you have multiple Mappings with the same metadata.name but in different metadata.namespaces, then any updates to these Mappings will only happen in the first (when sorted alphanumerically) Mapping. The envoy config for the the remaining Mappings will only ever be updated when the pods restart. A workaround is available by not using the same metadata.name for multiple Mappings.

Related Issues

N/A

Testing

I did some manual testing to inspect the logs/envoy config generated that I used to construct the unit test additions to the cache tests.

Checklist

• I made sure to update CHANGELOG.md.

  Remember, the CHANGELOG needs to mention:

  • Any new features
  • Any changes to our included version of Envoy
  • Any non-backward-compatible changes
  • Any deprecations

• This is unlikely to impact how Ambassador performs at scale.

  Remember, things that might have an impact at scale include:

  • Any significant changes in memory use that might require adjusting the memory limits
  • Any significant changes in CPU use that might require adjusting the CPU limits
  • Anything that might change how many replicas users should use
  • Changes that impact data-plane latency/scalability

• My change is adequately tested.

  Remember when considering testing:

  • Your change needs to be specifically covered by tests.
    • Tests need to cover all the states where your change is relevant: for example, if you add a behavior that can be enabled or disabled, you'll need tests that cover the enabled case and tests that cover the disabled case. It's not sufficient just to test with the behavior enabled.
  • You also need to make sure that the entire area being changed has adequate test coverage.
    • If existing tests don't actually cover the entire area being changed, add tests.
    • This applies even for aspects of the area that you're not changing – check the test coverage, and improve it if needed!
  • We should lean on the bulk of code being covered by unit tests, but...
  • ... an end-to-end test should cover the integration points

• I updated DEVELOPING.md with any any special dev tricks I had to use to work on this code efficiently.

• The changes in this PR have been reviewed for security concerns and adherence to security best practices.

[LanceEa]

Everything looks good...two quick questions on the test to make sure I understand it.

[LanceEa]

lgtm and CI is green so go for it. Great work identifying and getting this fixed!