This commit introduces GRPC API for streaming sessions.
It adds structured events and sync streaming
that avoids storing events on disk.
You can find design in rfd/0002-streaming.md RFD.
* Always collect metrics about top backend requests
Previously, it was only done in debug mode. This makes some tabs in
`tctl top` empty, when auth server is not in debug mode.
* backend: use an LRU cache for top requests in Reporter
This LRU cache tracks the most frequent recent backend keys. All keys in
this cache map to existing labels in the requests metric. Any evicted
keys are also deleted from the metric.
This will keep an upper limit on our memory usage while still always
reporting the most active keys.
This is a result of "go mod vendor".
You'll notice that some versions have changed. This is due to the
transient module dependencies that dep wasn't aware of.
For example:
- Gopkg.lock imported cloud.google.com/go v0.41.0 and
github.com/fsouza/fake-gcs-server v1.11.6
- github.com/fsouza/fake-gcs-server v1.11.6 has a go.mod file that
depends on cloud.google.com/go v0.43.3:
https://github.com/fsouza/fake-gcs-server/blob/v1.11.6/go.mod#L4
- therefore, "go mod vendor" bumped cloud.google.com/go to v.0.43.3
Same transient dependency version bumps got applied to some other
modules.
A few are also removed via "go mod tidy".
