cloudevents: relax requirement level for type and version (open-telem…

…etry#2618)

CHANGELOG.md

@@ -25,6 +25,8 @@ release.
   ([#2594](https://github.com/open-telemetry/opentelemetry-specification/pull/2594))
 - Add semantic conventions for GraphQL
   ([#2456](https://github.com/open-telemetry/opentelemetry-specification/pull/2456))
+- Change `cloudevents.event_spec_version` and `cloudevents.event_type` level from `required` to `recommended`
+  ([#2618](https://github.com/open-telemetry/opentelemetry-specification/pull/2618))
 
 ### Compatibility
 

semantic_conventions/trace/cloudevents.yaml

@@ -20,13 +20,11 @@ groups:
         examples: ['https://github.com/cloudevents', '/cloudevents/spec/pull/123', 'my-service' ]
       - id: event_spec_version
         type: string
-        requirement_level: required
         brief: >
           The [version of the CloudEvents specification](https://github.com/cloudevents/spec/blob/v1.0.2/cloudevents/spec.md#specversion) which the event uses.
         examples: '1.0'
       - id: event_type
         type: string
-        requirement_level: required
         brief: >
           The [event_type](https://github.com/cloudevents/spec/blob/v1.0.2/cloudevents/spec.md#type) contains a value describing the type of event related to the originating occurrence.
         examples: ['com.github.pull_request.opened', 'com.example.object.deleted.v2']

specification/trace/semantic_conventions/cloudevents.md

@@ -198,7 +198,7 @@ The following attributes are applicable to creation and processing Spans.
 |---|---|---|---|---|
 | `cloudevents.event_id` | string | The [event_id](https://github.com/cloudevents/spec/blob/v1.0.2/cloudevents/spec.md#id) uniquely identifies the event. | `123e4567-e89b-12d3-a456-426614174000`; `0001` | Required |
 | `cloudevents.event_source` | string | The [source](https://github.com/cloudevents/spec/blob/v1.0.2/cloudevents/spec.md#source-1) identifies the context in which an event happened. | `https://github.com/cloudevents`; `/cloudevents/spec/pull/123`; `my-service` | Required |
-| `cloudevents.event_spec_version` | string | The [version of the CloudEvents specification](https://github.com/cloudevents/spec/blob/v1.0.2/cloudevents/spec.md#specversion) which the event uses. | `1.0` | Required |
-| `cloudevents.event_type` | string | The [event_type](https://github.com/cloudevents/spec/blob/v1.0.2/cloudevents/spec.md#type) contains a value describing the type of event related to the originating occurrence. | `com.github.pull_request.opened`; `com.example.object.deleted.v2` | Required |
+| `cloudevents.event_spec_version` | string | The [version of the CloudEvents specification](https://github.com/cloudevents/spec/blob/v1.0.2/cloudevents/spec.md#specversion) which the event uses. | `1.0` | Recommended |
+| `cloudevents.event_type` | string | The [event_type](https://github.com/cloudevents/spec/blob/v1.0.2/cloudevents/spec.md#type) contains a value describing the type of event related to the originating occurrence. | `com.github.pull_request.opened`; `com.example.object.deleted.v2` | Recommended |
 | `cloudevents.event_subject` | string | The [subject](https://github.com/cloudevents/spec/blob/v1.0.2/cloudevents/spec.md#subject) of the event in the context of the event producer (identified by source). | `mynewfile.jpg` | Recommended |
 <!-- endsemconv -->