docs: Rework of logs data model doc

[thompson-tomo]

Fixes #4735

Changes

This removes the resource and instrument scope fields from the log data model as they are not fields on the log record but rather higher level otlp fields.

The other changes are an attempt to align the document structure with that used in the metric data model doc.

For non-trivial changes, follow the change proposal process.

• Related issues #
• Related OTEP(s) #
• Links to the prototypes (when adding or changing features)
• CHANGELOG.md file updated for non-trivial changes
• Spec compliance matrix updated if necessary

[jsuereth]

I'm not sure I understand this PR.

DataModel != OTLP. We encode things into OTLP where the data model may not exactly match how things are encoded in OTLP, as OTLP is a protocol. We may have different protocols in the future where things are structured differently, but logs will still need a Resource + instrumentation scope.

I do not think this should be removed.

cc @jack-berg / @tigrannajaryan for thoughts.

[thompson-tomo]

The key thing the page says

Here is the list of fields in a log record:

The 2 fields removed are not in fact fields in the log record as discussed with @pellared who is the sponsor of changes based on the linked issue.

If you look at metrics https://opentelemetry.io/docs/specs/otel/metrics/data-model/#opentelemetry-protocol-data-model there it mentions the metric is identified based on resource/scope with the metric defined using a collection of properties which doesn't include resource/scope. Logs are no different.

[pellared]

The 2 fields removed are not in fact fields in the log record as discussed with @pellared who is the sponsor of changes based on the linked issue.

There should be something which describes the record's relationship to instrumentation scope and resource.

Also notice the lint errors from https://github.com/open-telemetry/opentelemetry-specification/actions/runs/19997659863/job/57347719833?pr=4783:

[home/repo/specification/logs/api.md]:
Error:  file:///home/repo/specification/logs/data-model.md#field-instrumentationscope | Cannot find fragment: Fragment not found in document. Check if fragment exists or page structure

[home/repo/specification/logs/README.md]:
Error:  file:///home/repo/specification/logs/data-model.md#field-resource | Cannot find fragment: Fragment not found in document. Check if fragment exists or page structure

[home/repo/specification/logs/sdk.md]:
Error:  file:///home/repo/specification/logs/data-model.md#field-instrumentationscope | Cannot find fragment: Fragment not found in document. Check if fragment exists or page structure
Error:  file:///home/repo/specification/logs/data-model.md#field-resource | Cannot find fragment: Fragment not found in document. Check if fragment exists or page structure

If you look at metrics https://opentelemetry.io/docs/specs/otel/metrics/data-model/#opentelemetry-protocol-data-model there it mentions the metric is identified based on resource/scope with the metric defined using a collection of properties which doesn't include resource/scope. Logs are no different.

The Data Model specification structure is different for Metrics and Logs. Do you want to unify the document structure?

[pellared]

@thompson-tomo, are you planning to work on this?

[thompson-tomo]

Sorry missed the previous comment. I have made an attempt to update the structure of the logs data model doc to be more like the metrics equivalent.

I have tried to keep text changes to a minimum with alot of the changes coming from re-organising sections.