Remove the Jaeger Exporter

[pellared]

Fixes #3980

Follows #3551

Leftover after #3567:

The PR is now revised as follows:

• the Jaeger Exporter is removed

[pellared]

@marcalff Can you double-check please?

[marcalff]

@marcalff Can you double-check please?

I tried to remove file specification/trace/sdk_exporters/jaeger.md before, but Yuri had concerns about preserving the content.

See #3567 (comment)

Please check with @yurishkuro

[pellared]

See #3567 (comment)

I don't think we should delete this, rather it should be moved somewhere collector-related.

1. AFAIK Collector has also removed this exporter. I guess the comment is outdated. CC @open-telemetry/collector-approvers
2. Having it as listed as a Tracing SDK exporter feels wrong.

[marcalff]

See #3567 (comment)

I don't think we should delete this, rather it should be moved somewhere collector-related.

1. AFAIK Collector has also removed this exporter. I guess the comment is outdated. CC @open-telemetry/collector-approvers

2. Having it as listed as a Tracing SDK exporter feels wrong.

To clarify, I am fine with this cleanup, which I support, as the Jaeger exporter is no longer used.

However, I am not in a position to formally approve it, having no voice for specs.

[mx-psi]

In the Collector, we removed the Jaeger exporter on v0.86.0, specifically on open-telemetry/opentelemetry-collector-contrib/pull/26546

[yurishkuro]

So the situation today is that because in the past OTEL needed to transform to Jaeger format we wrote this transformation spec and there is a transformer in collector-contrib matching that spec. Even though the exporters in both SDK and collector may be safely removed now, the transformer is still actively used by Jaeger itself. So the simplest solution is to move the transformer spec to the transformer dir in collector-contrib. Longer term we can consider migrating that code completely to Jaeger, but the transformer is technically a public API in the contrib, we don't know if other people are also using it.

Requesting changes.

[pellared]

@open-telemetry/collector-contrib-maintainer, what do you think of @yurishkuro proposal: #3964 (review)? Are you fine moving the spec to collector-contrib? If so then I think this PR should blocked until the spec is added to collector.

[mx-psi]

Per our CODEOWNERS pkg/translator/jaeger is owned by @open-telemetry/collector-approvers and @frzifus. As part of said group I am in favor of moving the spec to collector-contrib for now, though personally I would like to see collector-contrib eventually be exclusively for components and move this library to some other repository

[yurishkuro]

I'd be fine with hosting the lib as a standalone repo in the jaeger org. At some point, if we convert the main jaeger repo into multi-module monorepo we could move it there.

[pellared]

@mx-psi I created #3980 for tracking (and marked this PR as blocked).

[pellared]

Ready to review as open-telemetry/opentelemetry-collector-contrib#32187 is already merged.