* Fix some tracing issues.
- Add endpoints for `startUpdate` and `postEngineEventsBatch` so that
spans for these invocations have proper names
- Inject a tracing span when walking a plan so that resource operations
are properly parented
- When handling gRPC calls, inject a tracing span into the call's
metadata if no span is already present so that resource monitor and
engine spans are properly parented
- Do not trace client gRPC invocations of the empty method so that these
calls (which are used to determine server availability) do not muddy
the trace. Note that I tried parenting these spans appropriately, but
doing so broke the trace entirely.
With these changes, the only unparented span in a typical Pulumi
invocation is a single call to `getUser`. This span is unparented
because that call does not have a context available. Plumbing a context
into that particular call is surprisingly tricky, as it is often called
by other context-less functions.
* Make tracing support more flexible.
- Add support for writing trace data to a local file using Appdash
- Add support for viewing Appdash traces via the CLI
These changes add support for injecting client tracing spans into HTTP
requests to the Pulumi API. The server can then rematerialize these span
references and attach its own spans for distributed tracing.
These changes enable tracing of Pulumi API calls.
The span with which to associate an API call is passed via a
`context.Context` parameter. This required plumbing a
`context.Context` parameter through a rather large number of APIs,
especially in the backend.
In general, all API calls are associated with a new root span that
exists for essentially the entire lifetime of an invocation of the
Pulumi CLI. There were a few places where the plumbing got a bit hairier
than I was willing to address with these changes; I've used
`context.Background()` in these instances. API calls that receive this
context will create new root spans, but will still be traced.
Adds OpenTracing in the Pulumi engine and plugin + langhost subprocesses.
We currently create a single root span for any `Enging.plan` operation - which is a single `preview`, `update`, `destroy`, etc.
The only sub-spans we currently create are at gRPC boundaries, both on the client and server sides and on both the langhost and provider plugin interfaces.
We could extend this to include spans for any other semantically meaningful sections of compute inside the engine, though initial examples show we get pretty good granularity of coverage by focusing on the gRPC boundaries.
In the future, this should be easily extensible to HTTP boundaries and to track other bulky I/O like datastore read/writes once we hook up to the PPC and Pulumi Cloud.
We expose a `--trace <endpoint>` option to enable tracing on the CLI, which we will aim to thread through to subprocesses.
We currently support sending tracing data to a Zipkin-compatible endpoint. This has been validated with both Zipkin and Jaeger UIs.
We do not yet have any tracing inside the TypeScript side of the JS langhost RPC interface. There is not yet automatic gRPC OpenTracing instrumentation (though it looks like it's in progress now) - so we would need to manually create meaningful spans on that side of the interface.
