ssl_multicert.config -> ssl_multicert.yaml

[bneradt]

Replace the ssl_multicert.config format with YAML format, following the pattern established by sni.yaml. The new ssl_multicert.yaml uses a top-level 'ssl_multicert' key containing a sequence of certificate entries.

This also supports config conversion via:

traffic_ctl config ssl_multicert <old_config> <new_config>

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Community Decisions

• Do we want these conversion scripts to be python or c++ files? This implements the conversion via traffic_ctl config convert per @cmcfarlen 's suggestion.
• Do we want to support both the old and new formats at the same time? At 10.x, we transitioned to only supporting records.yaml, so we have that as maybe something of a precedent. This PR supports both the old and new formats, but we have to decide on our policy for the old formats for 11.

At least for ssl_multicert, either of these options are possible from an implementation standpoint.

@cmcfarlen had an interesting suggestion to bake the config conversion logic into traffic_ctl. Maybe have something like:

traffic_ctrl config convert ssl_multicert|plugins|... <old_path> <new_path>

[Copilot]

Copilot reviewed 198 out of 198 changed files in this pull request and generated 2 comments.

Comments suppressed due to low confidence (3)

tests/gold_tests/tls/tls_check_dual_cert_selection.test.py:56

• The test is still using legacy format syntax in AddLines() after changing from ssl_multicert_config to ssl_multicert_yaml. Lines 53-56 contain legacy format entries like 'ssl_cert_name=signed-foo-ec.pem,signed-foo.pem' which should be converted to YAML format to match the migration pattern used consistently in other test files.
  tests/gold_tests/tls/tls_check_cert_select_plugin.test.py:52
• Similar to tls_check_dual_cert_selection.test.py, this test is still using legacy format syntax after changing to ssl_multicert_yaml. Lines 49-52 should be converted to YAML format to be consistent with the migration pattern.
  tests/gold_tests/tls/tls_check_cert_selection_reload.test.py:46
• This test is still using legacy format syntax in AddLines() after changing to ssl_multicert_yaml. Lines 44-46 contain legacy format entries which should be converted to YAML format for consistency.

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[cmcfarlen]

I really like the concept of having parsing code and conversions in one place. It's really clean to do the conversion natively with traffic_ctl. I do think the runtime code should also use this code to load config as well so there isn't code duplication.