This PR aims to de-experimentalize the APIs for GCP Observability.
We would have ideally wanted public feedback before declaring the APIs
stable, but we need stable APIs for GA.
Changes made after API review with @markdroth @veblush, @ctiller and the
entire Core/C++ team -
* The old experimental APIs `grpc::experimental::GcpObservabilityInit`
and `grpc::experimental::GcpObservabilityClose` are now deprecated and
will be deleted after v.1.55 release.
* The new API gets rid of the Close method and follows the RAII idiom
with a single `grpc::GcpObservability::Init()` call that returns an
`GcpObservability` object, the lifetime of which controls when
observability data is flushed.
* The `GcpObservability` class could in the future add more methods. For
example, a debug method that shows the current configuration.
* Document that GcpObservability initialization and flushing (on
`GcpObservability` destruction) are blocking calls.
* Document that gRPC is still usable if GcpObservability initialization
failed. (Added a test to prove the same).
* Since we don't have a good way to flush stats and tracing with
OpenCensus, the examples required users to sleep for 25 seconds. This
sleep is now part of `GcpObservability` destruction.
Additional Implementation details -
* `GcpObservability::Init` is now marked with `GRPC_MUST_USE_RESULT` to
make sure that the results are used. We ideally want users to store it,
but this is better than nothing.
* Added a note on GCP Observability lifetime guarantees.
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This code is not plumbed through yet, but it provides the core
infrastructure needed to detect the proper GCP environment resources
needed to set up the labels/attributes/resources for stats, tracing and
logging.
Details on how the various environment resources are setup has been
derived by looking at java's cloud logging library and OpenTelemetry's
future plans. (Could be better explained in an offline review since some
links are internal).
Requesting @veblush for a full review and @markdroth for a structural
review.
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* initial
* Intermediate
* Another try
* Try multiple necesary pulls
* Filter works other than client half close
* Fixes
* Add a cancelled RPC test
* Handle trailer only responses
* Tests for disabled logging and truncated payloads
* Fix authority and peer
* Add TODOs and asserts for half-close
* Fix tests for half-close and cancel
* 2d748fcb1cf45cac62729b8346ad15e6abc79e97
* Fix sanity checks
* Strict bazel build
* Fix package
* IWYU
* Fix cmake
* Explicit cast to string
* Size casts
* Fix Arena leak and disable macos build for now
* Reviewer comments
Yash Tibrewal