# 0019: Introduce rpc fieldset
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- Stage: **0 (strawperson)** <!-- Update to reflect target stage. See https://elastic.github.io/ecs/stages.html -->
- Date: **2021-04-14** <!-- The ECS team sets this date at merge time. This is the date of the latest stage advancement. -->

We would like to introduce a new, top-level, `rpc` fieldset.  This fieldset would be suitable for recording information pertaining to RPCs (Remote Procedure Calls),
such as the RPC system (e.g. gRPC, Thrift, Java RMI), service name, method name, and response status code.

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## Fields

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## Usage

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## Source data

Initially the `rpc` fieldset will be populated by Elastic APM when translating [OpenTelemetry RPC semantic conventions][0].
Later, Elastic APM may add support for RPC fields to its own protocol, for native RPC (namely gRPC) client and server instrumentation, and these too would result in ECS `rpc` fields.

Custom appication logs would be another potential data source.

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## Scope of impact

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## Concerns

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## People

The following are the people that consulted on the contents of this RFC.

* @axw | author

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## References

* [OpenTelemetry RPC semantic conventions][0]

### RFC Pull Requests

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* Stage 0: https://github.com/elastic/ecs/pull/1357

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[0]: https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/trace/semantic_conventions/rpc.md
