# RPC - [RPC Attributes](#rpc-attributes) - [Deprecated RPC Attributes](#deprecated-rpc-attributes) ## RPC Attributes RPC attributes are intended to be used in the context of events related to remote procedure calls (RPC). | Attribute | Type | Description | Examples | Stability | |---|---|---|---|---| | `rpc.connect_rpc.error_code` | string | The [error codes](https://connect.build/docs/protocol/#error-codes) of the Connect request. Error codes are always string values. | `cancelled` |  | | `rpc.connect_rpc.request.metadata.` | string[] | Connect request metadata, `` being the normalized Connect Metadata key (lowercase), the value being the metadata values. [1] | `rpc.request.metadata.my-custom-metadata-attribute=["1.2.3.4", "1.2.3.5"]` |  | | `rpc.connect_rpc.response.metadata.` | string[] | Connect response metadata, `` being the normalized Connect Metadata key (lowercase), the value being the metadata values. [2] | `rpc.response.metadata.my-custom-metadata-attribute=["attribute_value"]` |  | | `rpc.grpc.request.metadata.` | string[] | gRPC request metadata, `` being the normalized gRPC Metadata key (lowercase), the value being the metadata values. [3] | `rpc.grpc.request.metadata.my-custom-metadata-attribute=["1.2.3.4", "1.2.3.5"]` |  | | `rpc.grpc.response.metadata.` | string[] | gRPC response metadata, `` being the normalized gRPC Metadata key (lowercase), the value being the metadata values. [4] | `rpc.grpc.response.metadata.my-custom-metadata-attribute=["attribute_value"]` |  | | `rpc.grpc.status_code` | int | The [numeric status code](https://github.com/grpc/grpc/blob/v1.33.2/doc/statuscodes.md) of the gRPC request. | `0` |  | | `rpc.jsonrpc.error_code` | int | `error.code` property of response if it is an error response. | `-32700`; `100` |  | | `rpc.jsonrpc.error_message` | string | `error.message` property of response if it is an error response. | `Parse error`; `User already exists` |  | | `rpc.jsonrpc.request_id` | string | `id` property of request or response. Since protocol allows id to be int, string, `null` or missing (for notifications), value is expected to be cast to string for simplicity. Use empty string in case of `null` value. Omit entirely if this is a notification. | `10`; `request-7`; `` |  | | `rpc.jsonrpc.version` | string | Protocol version as in `jsonrpc` property of request/response. Since JSON-RPC 1.0 doesn't specify this, the value can be omitted. | `2.0`; `1.0` |  | | `rpc.message.compressed_size` | int | Compressed size of the message in bytes. | |  | | `rpc.message.id` | int | MUST be calculated as two different counters starting from `1` one for sent messages and one for received message. [5] | |  | | `rpc.message.type` | string | Whether this is a received or sent message. | `SENT` |  | | `rpc.message.uncompressed_size` | int | Uncompressed size of the message in bytes. | |  | | `rpc.method` | string | The name of the (logical) method being called, must be equal to the $method part in the span name. [6] | `exampleMethod` |  | | `rpc.service` | string | The full (logical) name of the service being called, including its package name, if applicable. [7] | `myservice.EchoService` |  | | `rpc.system` | string | A string identifying the remoting system. See below for a list of well-known identifiers. | `grpc` |  | **[1]:** Instrumentations SHOULD require an explicit configuration of which metadata values are to be captured. Including all request metadata values can be a security risk - explicit configuration helps avoid leaking sensitive information. **[2]:** Instrumentations SHOULD require an explicit configuration of which metadata values are to be captured. Including all response metadata values can be a security risk - explicit configuration helps avoid leaking sensitive information. **[3]:** Instrumentations SHOULD require an explicit configuration of which metadata values are to be captured. Including all request metadata values can be a security risk - explicit configuration helps avoid leaking sensitive information. **[4]:** Instrumentations SHOULD require an explicit configuration of which metadata values are to be captured. Including all response metadata values can be a security risk - explicit configuration helps avoid leaking sensitive information. **[5]:** This way we guarantee that the values will be consistent between different implementations. **[6]:** This is the logical name of the method from the RPC interface perspective, which can be different from the name of any implementing method/function. The `code.function` attribute may be used to store the latter (e.g., method actually executing the call on the server side, RPC client stub method on the client side). **[7]:** This is the logical name of the service from the RPC interface perspective, which can be different from the name of any implementing class. The `code.namespace` attribute may be used to store the latter (despite the attribute name, it may include a class name; e.g., class with method actually executing the call on the server side, RPC client stub class on the client side). `rpc.connect_rpc.error_code` MUST be one of the following: | Value | Description | Stability | |---|---|---| | `cancelled` | cancelled |  | | `unknown` | unknown |  | | `invalid_argument` | invalid_argument |  | | `deadline_exceeded` | deadline_exceeded |  | | `not_found` | not_found |  | | `already_exists` | already_exists |  | | `permission_denied` | permission_denied |  | | `resource_exhausted` | resource_exhausted |  | | `failed_precondition` | failed_precondition |  | | `aborted` | aborted |  | | `out_of_range` | out_of_range |  | | `unimplemented` | unimplemented |  | | `internal` | internal |  | | `unavailable` | unavailable |  | | `data_loss` | data_loss |  | | `unauthenticated` | unauthenticated |  | `rpc.grpc.status_code` MUST be one of the following: | Value | Description | Stability | |---|---|---| | `0` | OK |  | | `1` | CANCELLED |  | | `2` | UNKNOWN |  | | `3` | INVALID_ARGUMENT |  | | `4` | DEADLINE_EXCEEDED |  | | `5` | NOT_FOUND |  | | `6` | ALREADY_EXISTS |  | | `7` | PERMISSION_DENIED |  | | `8` | RESOURCE_EXHAUSTED |  | | `9` | FAILED_PRECONDITION |  | | `10` | ABORTED |  | | `11` | OUT_OF_RANGE |  | | `12` | UNIMPLEMENTED |  | | `13` | INTERNAL |  | | `14` | UNAVAILABLE |  | | `15` | DATA_LOSS |  | | `16` | UNAUTHENTICATED |  | `rpc.message.type` MUST be one of the following: | Value | Description | Stability | |---|---|---| | `SENT` | sent |  | | `RECEIVED` | received |  | `rpc.system` has the following list of well-known values. If one of them applies, then the respective value MUST be used; otherwise, a custom value MAY be used. | Value | Description | Stability | |---|---|---| | `grpc` | gRPC |  | | `java_rmi` | Java RMI |  | | `dotnet_wcf` | .NET WCF |  | | `apache_dubbo` | Apache Dubbo |  | | `connect_rpc` | Connect RPC |  | ## Deprecated RPC Attributes | Attribute | Type | Description | Examples | Stability | |---|---|---|---|---| | `message.compressed_size` | int | Deprecated, use `rpc.message.compressed_size` instead. | | 
Replaced by `rpc.message.compressed_size`. | | `message.id` | int | Deprecated, use `rpc.message.id` instead. | | 
Replaced by `rpc.message.id`. | | `message.type` | string | Deprecated, use `rpc.message.type` instead. | `SENT` | 
Replaced by `rpc.message.type`. | | `message.uncompressed_size` | int | Deprecated, use `rpc.message.uncompressed_size` instead. | | 
Replaced by `rpc.message.uncompressed_size`. | `message.type` MUST be one of the following: | Value | Description | Stability | |---|---|---| | `SENT` | sent |  | | `RECEIVED` | received |  |