OpenTelemetry’s First Release Candidates

OpenTelemetry has hit another milestone with the tracing specification reaching release candidate status.

With the specification now ready to go, expect to see tracing release candidates of the official APIs and SDKs over the next few weeks, along with updated exporters for Cloud Trace. In the coming months the same will follow for the metrics specification, followed by metrics release candidates of the APIs and SDKs and Cloud Monitoring exporters, followed by the project’s general availability. At this point we’ll switch our default application metrics and distributed tracing instrumentation from OpenCensus to OpenTelemetry.

This is exciting news for Google Cloud customers, as OpenTelemetry will enable even better observability experiences, both with Cloud Monitoring and Cloud Trace, or the third party monitoring and operations tools of your choice.

Originally posted on the on the OpenTelemetry blog.


As we’ve discussed in past announcements, we’re hard at work building OpenTelemetry’s first GA quality release. Today marks another milestone in this journey, with the freezing and first release candidate of the tracing specification.
Tracing Spec Release Candidate

The tracing specification is now considered to be a release candidate (RC) and is frozen, and the OpenTelemetry APIs and SDKs have a stable specification to build their own release candidates against. This means:
  • API, SDK, and Collector release candidates will appear within the next few weeks.
  • No breaking spec changes are allowed between now and the final GA specification, beyond any showstopper (P1) issues that are revealed in the RC period. We don’t expect any of these to appear, but the purpose of the RC period is for us to validate that we have a GA-worthy spec.
  • Some non-breaking changes will be allowed during the RC period. Most of these are clarifications of existing behaviour or are pure editorial updates.
The release candidate sections of the specification include all tracing related dependencies, specifically the following sections: Trace, Baggage, Resource, Context Propagation, Environment Variables, Exporters (for traces). You can view the progress of each OpenTelemetry component’s implementation in the project status matrix.

What’s Coming Next?

Achieving a release candidate of the tracing specification has been the top priority of OpenTelemetry since releasing our beta in March. With this completed, our focus now shifts to tracing release candidates of the APIs, SDKs, Collector, and auto instrumentation components, and producing a release candidate of the metrics specification.

RC Tracing Implementations

Most OpenTelemetry APIs and SDKs are close to completing their tracing RC implementations, and we expect the first wave of these to arrive within the next two weeks. Contributors who are looking to provide instrumentation (for various web frameworks, storage clients, etc.) can start building against release candidate APIs once they arrive. While the APIs may change in response to issues discovered during RC usage and testing (which will result in multiple pre-GA release candidates for these components), these will be extremely constrained.

Several SDKs will have two waves of release candidate milestones: the first will contain functionality from the tracing and context propagation sections of the specification, and the second will include release candidate implementations for baggage, exporters, resources, and environment variables.

Metrics

In parallel to the tracing RC component releases, we will apply the focus that we’ve had on tracing to the metrics specification. Starting this week, we will categorize which work items are required for GA, which can be optionally allowed in GA (non-breaking), and which will be shifted to post-GA. After completing this, we will track our burndown progress, and lock the metrics specification and publish a metrics specification release candidate once all P1 items are complete. Shortly after this, the APIs, SDKs, Collector, and other components will publish release candidates with RC-quality tracing and metrics functionality.

Productionization and GA Readiness Work

Once the metrics specification, SDKs, Collector, and other components reach release candidate status, we will focus on productionization tasks like writing documentation, producing a post-GA versioning strategy, building additional automated tests, etc. Once we are satisfied with each component’s adoptability and reliability, we will announce their general availability.

Overall Timeline

  1. Components (APIs, SDKs, Collector, auto instrumentation, etc.) issue release candidates with RC-quality tracing functionality.
  2. The metrics section of the specification achieves RC quality and is frozen.
  3. Components issue release candidates with RC-quality tracing and metrics functionality.
  4. Once we are satisfied with our metrics + tracing release candidates, OpenTelemetry goes GA.
  5. Logging enters beta, then issues an RC specification, followed by RC-quality logging functionality in each component, followed by a GA for logging.
We will have a better understanding of our GA release timeline in the coming weeks once outstanding work on the metrics specification is fully accounted for.

Tracking a Language’s Progress

As mentioned above, you can view the progress of a particular component (API, SDK, etc.) in the project status matrix. Each component’s implementation has their own timeline, though a core set (the JavaScript, Java, Go, Python, and .Net APIs + SDKs, the Collector, and Java auto instrumentation) are all tracking well. Each component has its own GA burndown board.

FAQ

I want to use OpenTelemetry on my production services; what’s the impact of today’s announcement?

SDKs with release candidate quality tracing support will be available in a few weeks. Release candidates are not recommended for critical production services, however they are functional and are intended to offer APIs that are compatible with their upcoming GA counterparts.

I want to write instrumentation for OpenTelemetry; what’s the impact of today’s announcement?

APIs with release candidate quality tracing support will be available shortly (prior to the SDKs). You can bind against these to produce traces that will be picked up by the OpenTelemetry SDKs or any other implementations that implement the OpenTelemetry APIs.

When will OpenTelemetry offer drop-in replacements for OpenCensus and OpenTracing?

Work is currently underway on bridge APIs that allow OpenTelemetry SDKs to seamlessly replace OpenCensus libraries or OpenTracing implementations. While the delivery date of this functionality is not tied to OpenTelemetry’s GA goals, we expect this to arrive between each API + SDK’s release candidate and GA milestones.

Wrapping Up

Producing a specification release candidate is an important milestone for the OpenTelemetry community, and it took significant effort on the part of our contributors to make this happen. We’d like to thank every person and every organization that was a part of this release, and to recognize that their contributions are laying the groundwork for the project's long term success.

If you haven’t been a part of the OpenTelemetry community but would like to join, now is the perfect time! OpenTelemetry is now in the top three CNCF projects by weekly and cumulative commits, and no matter your level of commitment (ha!) to the project, contributions are always welcome. If you have a particular area that you’re interested in (for example, the Python API + SDK), the best way to get involved is to join the relevant weekly SIG meetings or interact with other contributors on Gitter.

By Morgan McLean, Google Cloud