This adds support for the Incremental xDS protocol when using xDS v3. This is best reviewed commit-by-commit and will not be squashed when merged.
Union of all commit messages follows to give an overarching summary:
xds: exclusively support incremental xDS when using xDS v3
Attempts to use SoTW via v3 will fail, much like attempts to use incremental via v2 will fail.
Work around a strange older envoy behavior involving empty CDS responses over incremental xDS.
xds: various cleanups and refactors that don't strictly concern the addition of incremental xDS support
Dissolve the connectionInfo struct in favor of per-connection ResourceGenerators instead.
Do a better job of ensuring the xds code uses a well configured logger that accurately describes the connected client.
xds: pull out checkStreamACLs method in advance of a later commit
xds: rewrite SoTW xDS protocol tests to use protobufs rather than hand-rolled json strings
In the test we very lightly reuse some of the more boring protobuf construction helper code that is also technically under test. The important thing of the protocol tests is testing the protocol. The actual inputs and outputs are largely already handled by the xds golden output tests now so these protocol tests don't have to do double-duty.
This also updates the SoTW protocol test to exclusively use xDS v2 which is the only variant of SoTW that will be supported in Consul 1.10.
xds: default xds.Server.AuthCheckFrequency at use-time instead of construction-time
This has the biggest impact on enterprise test cases that use namespaced
registrations, which prior to this change sometimes failed the initial
registration because the namespace was not yet created.
* Allow setting the mesh gateway mode for an upstream in config files
* Add envoy integration test for mesh gateways
This necessitated many supporting changes in most of the other test cases.
Add remote mode mesh gateways integration test
* Add support for HTTP proxy listeners
* Add customizable bootstrap configuration options
* Debug logging for xDS AuthZ
* Add Envoy Integration test suite with basic test coverage
* Add envoy command tests to cover new cases
* Add tracing integration test
* Add gRPC support WIP
* Merged changes from master Docker. get CI integration to work with same Dockerfile now
* Make docker build optional for integration
* Enable integration tests again!
* http2 and grpc integration tests and fixes
* Fix up command config tests
* Store all container logs as artifacts in circle on fail
* Add retries to outer part of stats measurements as we keep missing them in CI
* Only dump logs on failing cases
* Fix typos from code review
* Review tidying and make tests pass again
* Add debug logs to exec test.
* Fix legit test failure caused by upstream rename in envoy config
* Attempt to reduce cases of bad TLS handshake in CI integration tests
* bring up the right service
* Add prometheus integration test
* Add test for denied AuthZ both HTTP and TCP
* Try ANSI term for Circle
R.B. Boyer