[go] new key cache backend: "simple"

[aka-bo]

To help us get this pull request reviewed and merged quickly, please be sure to include the following items:

• [x] Tests (if applicable)
• [ ] Documentation (if applicable)
• [ ] Changelog entry
• [x] A full explanation here in the PR description of the work done

PR Type

What kind of change does this PR introduce?

• [ ] Bugfix
• [x] Feature
• [ ] Code style update (formatting, local variables)
• [ ] Refactoring (no functional changes, no api changes)
• [ ] Build related changes
• [ ] CI related changes
• [ ] Documentation content changes
• [ ] Tests
• [ ] Other

Backward Compatibility

Is this change backward compatible with the most recently released version? Does it introduce changes which might change the user experience in any way? Does it alter the API in any way?

• [x] Yes (backward compatible)
• [ ] No (breaking changes)

What's new?

• SK and IK caching updated to use the new the "simple" cache backend by default. This lightweight cache.Interface implementation never evicts keys and is intended to provide a caching experience similar to that of previous versions of the SDK (<0.4.0).

benchstat v0.5.0-main.txt v0.6.0-pr1048.txt
goos: darwin
goarch: arm64
pkg: github.com/godaddy/asherah/go/appencryption
                                                               │ v0.5.0-main.txt │          v0.6.0-pr1048.txt          │
                                                               │     sec/op      │   sec/op     vs base                │
KeyCache_GetOrLoad_MultipleThreadsReadExistingKey-12                 2.096µ ± 1%   1.104µ ± 4%  -47.35% (p=0.000 n=10)
KeyCache_GetOrLoad_MultipleThreadsWriteSameKey-12                    3.912µ ± 1%   1.346µ ± 1%  -65.61% (p=0.000 n=10)
KeyCache_GetOrLoad_MultipleThreadsWriteUniqueKeys-12                31.696µ ± 1%   9.825µ ± 2%  -69.00% (p=0.000 n=10)
KeyCache_GetOrLoad_MultipleThreadsReadRevokedKey-12                  5.048µ ± 1%   1.497µ ± 2%  -70.34% (p=0.000 n=10)
KeyCache_GetOrLoad_MultipleThreadsRead_NeedReloadKey-12             1715.0n ± 2%   674.0n ± 1%  -60.70% (p=0.000 n=10)
KeyCache_GetOrLoad_MultipleThreadsReadUniqueKeys-12                  2.537µ ± 1%   1.812µ ± 1%  -28.56% (p=0.000 n=10)
KeyCache_GetOrLoadLatest_MultipleThreadsReadExistingKey-12           9.263µ ± 0%   3.070µ ± 0%  -66.86% (p=0.000 n=10)
KeyCache_GetOrLoadLatest_MultipleThreadsWriteSameKey-12             13.569µ ± 0%   2.602µ ± 1%  -80.82% (p=0.000 n=10)
KeyCache_GetOrLoadLatest_MultipleThreadsWriteUniqueKey-12           21.359µ ± 1%   5.022µ ± 2%  -76.49% (p=0.000 n=10)
KeyCache_GetOrLoadLatest_MultipleThreadsReadStaleRevokedKey-12       377.9µ ± 3%   403.0µ ± 1%   +6.64% (p=0.000 n=10)
KeyCache_GetOrLoadLatest_MultipleThreadsReadRevokedKey-12            8.098µ ± 0%   2.009µ ± 0%  -75.20% (p=0.000 n=10)
KeyCache_GetOrLoadLatest_MultipleThreadsReadUniqueKeys-12           12.354µ ± 1%   3.284µ ± 0%  -73.42% (p=0.000 n=10)
geomean                                                              9.555µ        3.450µ       -63.89%