Avoiding so many deps will allow us to upgrade the protos without being
forced to upgrade to protobuf-java 4.x. It also removes the remaining
non-bzlmod dependencies.
It'd be really easy to get this wrong, so we do two things 1) mirror the
gradle configuration as much as possible, as that sees a lot of testing,
and 2) run the fake control plane with the _results_ of jarjar. There's
lots of classes that we could mess up, but that at least kicks the tires.
XdsTestUtils.buildRouteConfiguration() was moved to ControlPlaneRule to
stop the unnecessary circular dependency between the classes and to
avoid the many dependencies of XdsTestUtils.
I'm totally hacking java_grpc_library to improve the dependency
situation. Long-term, I think we will stop building Java libraries with
Bazel and require users to rely entirely on Maven Central. That seems to
be the direction Bazel is going and it will greatly simplify the
problems we've seen with protobuf having a single repository for many
languages. So while the hack isn't too bad, I hope we won't have to live
with it long-term.
LoadBalancers shouldn't be called after shutdown(), but RingHashLb could
have enqueued work to the SynchronizationContext that executed after
shutdown(). This commit fixes problems discovered when auditing all LBs
usage of the syncContext for that type of problem.
Similarly, PickFirstLb could have requested a new connection after
shutdown(). We want to avoid that sort of thing too.
RingHashLb's test changed from CONNECTING to TRANSIENT_FAILURE to get
the latest picker. Because two subchannels have failed it will be in
TRANSIENT_FAILURE. Previously the test was using an older picker with
out-of-date subchannelView, and the verifyConnection() was too imprecise
to notice it was creating the wrong subchannel.
As discovered in b/430347751, where ClusterImplLb was seeing a new
subchannel being called after the child LB was shutdown (the shutdown
itself had been caused by RingHashConfig not implementing equals() and
was fixed by a8de9f07ab, which caused ClusterResolverLb to replace its
state):
```
java.lang.NullPointerException
at io.grpc.xds.ClusterImplLoadBalancer$ClusterImplLbHelper.createClusterLocalityFromAttributes(ClusterImplLoadBalancer.java:322)
at io.grpc.xds.ClusterImplLoadBalancer$ClusterImplLbHelper.createSubchannel(ClusterImplLoadBalancer.java:236)
at io.grpc.util.ForwardingLoadBalancerHelper.createSubchannel(ForwardingLoadBalancerHelper.java:47)
at io.grpc.util.ForwardingLoadBalancerHelper.createSubchannel(ForwardingLoadBalancerHelper.java:47)
at io.grpc.internal.PickFirstLeafLoadBalancer.createNewSubchannel(PickFirstLeafLoadBalancer.java:527)
at io.grpc.internal.PickFirstLeafLoadBalancer.requestConnection(PickFirstLeafLoadBalancer.java:459)
at io.grpc.internal.PickFirstLeafLoadBalancer.acceptResolvedAddresses(PickFirstLeafLoadBalancer.java:174)
at io.grpc.xds.LazyLoadBalancer$LazyDelegate.activate(LazyLoadBalancer.java:64)
at io.grpc.xds.LazyLoadBalancer$LazyDelegate.requestConnection(LazyLoadBalancer.java:97)
at io.grpc.util.ForwardingLoadBalancer.requestConnection(ForwardingLoadBalancer.java:61)
at io.grpc.xds.RingHashLoadBalancer$RingHashPicker.lambda$pickSubchannel$0(RingHashLoadBalancer.java:440)
at io.grpc.SynchronizationContext.drain(SynchronizationContext.java:96)
at io.grpc.SynchronizationContext.execute(SynchronizationContext.java:128)
at io.grpc.xds.client.XdsClientImpl$ResourceSubscriber.onData(XdsClientImpl.java:817)
```
The plugin now outputs to "generated/sources". The IDE configuration
explicitly adding the folders to the source sets hasn't been needed for
some years.
Bazel had the dependency added because of #5046, where Guava was
depending on it as compile-only and Bazel build have "unknown enum
constant" warnings. Guava now has a compile dependency on j2objc, so
this workaround is no longer needed. There are currently no version skew
issues in Gradle, which was the only usage.
The GSON upgrade slightly changed an error string, so the test was
updated to be less of a change detector.
Some OpenTelemetry dependencies are alpha versions, so needed an
adjustment in build.gradle to accept the versions. Similarly, Undertow
includes Final in its version numbers which needs to be accepted.
Add gRPC OpenTelemetry example. The example uses Prometheus exporter to export metrics and can be verified locally.
It also provides an example using LoggingMetricExporter to export and log the metrics using java.util.logging.
According to the docs, I can use bazel to build examples, but
retry-example is not supported in bazel config. So If you'll try to
build this example with bazel, you'll get an error:
```
examples git:(master) ✗ bazel build :retrying-hello-world-server :retrying-hello-world-client
ERROR: Skipping ':retrying-hello-world-client': no such target '//:retrying-hello-world-client': target 'retrying-hello-world-client' not declared in package '' defined by /Users/rostik404/projects/grpc-java/examples/BUILD.bazel
ERROR: no such target '//:retrying-hello-world-client': target 'retrying-hello-world-client' not declared in package '' defined by /Users/rostik404/projects/grpc-java/examples/BUILD.bazel
INFO: Elapsed time: 0.331s
INFO: 0 processes.
ERROR: Build did NOT complete successfully
```
The gradle wrapper was removed from example-oauth because we don't want
to maintain the wrapper copy in each example (at least right now it
doesn't make sense for it to be the only other example to have the
gradle wrapper).