Add native support for threading (new instrumentation package)

[owais]

OpenCensus has native integration for the threading module that automatically propagates tracing context across threads. It would be nice to port it over to OpenTelemetry.

OpenCensus Threading integration: https://github.com/census-instrumentation/opencensus-python/tree/master/contrib/opencensus-ext-threading

[rdpravin1895]

Currently, whats the best way to propagate tracing context across threads? I have been looking for it, but cannot find any reference snippet

[owais]

Passing context as an function argument to the thread and then setting the received context on the other side. There is no automated solution.

[jsmolina]

I did it by passing context and then re-attaching it:

from opentelemetry import context

def execute_ec2_func(method, data, ctx):
    context.attach(ctx)
    return method(**data)

Then the boto3 methods are called passing current context:

loop.run_in_executor(
 self.executor,
 execute_ec2_func,
 self.ec2.start_instances,
 {"InstanceIds": instance_ids},
 context.get_current(),
)

[srikanthccv]

@pridhi-arora, you will be working on this as part of the outreachy program. Please leave a comment here so that I can assign this to you.

[pridhi-arora]

Thanks, @srikanthccv. Looking forward to work on this.

[pridhi-arora]

What do we mean by propagate tracing context across threads? @srikanthccv Can you shed some light on this? Thanks in advance.

[ocelotl]

@bobthemighty for some reason I can't assign you to this issue 🤔 apparently you need to leave a comment here first.

[bobthemighty]

@ocelotl like this?