Resource Semantic Conventions

Status: Mixed

This document defines standard attributes for resources. These attributes are typically used in the Resource and are also recommended to be used anywhere else where there is a need to describe a resource in a consistent manner. The majority of these attributes are inherited from OpenCensus Resource standard.

TODOs

  • Add more compute units: AppEngine unit, etc.
  • Add Web Browser.
  • Decide if lower case strings only.
  • Consider to add optional/required for each attribute and combination of attributes (e.g when supplying a k8s resource all k8s may be required).

Document Conventions

Status: Stable

Attributes are grouped logically by the type of the concept that they described. Attributes in the same group have a common prefix that ends with a dot. For example all attributes that describe Kubernetes properties start with “k8s.”

See Attribute Requirement Levels for details on when attributes should be included.

Attributes with Special Handling

Status: Stable

Given their significance some resource attributes are treated specifically as described below.

Semantic Attributes with Dedicated Environment Variable

These are the attributes which MAY be configurable via a dedicated environment variable as specified in OpenTelemetry Environment Variable Specification:

Semantic Attributes with SDK-provided Default Value

These are the attributes which MUST be provided by the SDK as specified in the Resource SDK specification:

Service

Status: Stable

type: service

Description: A service instance.

Attribute Type Description Examples Requirement Level
service.name string Logical name of the service. [1] shoppingcart Required
service.version string The version string of the service API or implementation. The format is not defined by these conventions. 2.0.0; a01dbef8a Recommended

[1]: MUST be the same for all instances of horizontally scaled services. If the value was not specified, SDKs MUST fallback to unknown_service: concatenated with process.executable.name, e.g. unknown_service:bash. If process.executable.name is not available, the value MUST be set to unknown_service.

Service (Experimental)

Status: Experimental

type: service

Description: Additions to service instance.

Attribute Type Description Examples Requirement Level
service.instance.id string The string ID of the service instance. [1] my-k8s-pod-deployment-1; 627cc493-f310-47de-96bd-71410b7dec09 Recommended
service.namespace string A namespace for service.name. [2] Shop Recommended

[1]: MUST be unique for each instance of the same service.namespace,service.name pair (in other words service.namespace,service.name,service.instance.id triplet MUST be globally unique). The ID helps to distinguish instances of the same service that exist at the same time (e.g. instances of a horizontally scaled service). It is preferable for the ID to be persistent and stay the same for the lifetime of the service instance, however it is acceptable that the ID is ephemeral and changes during important lifetime events for the service (e.g. service restarts). If the service has no inherent unique ID that can be used as the value of this attribute it is recommended to generate a random Version 1 or Version 4 RFC 4122 UUID (services aiming for reproducible UUIDs may also use Version 5, see RFC 4122 for more recommendations).

[2]: A string value having a meaning that helps to distinguish a group of services, for example the team name that owns a group of services. service.name is expected to be unique within the same namespace. If service.namespace is not specified in the Resource then service.name is expected to be unique for all services that have no explicit namespace defined (so the empty/unspecified namespace is simply one more valid namespace). Zero-length namespace string is assumed equal to unspecified namespace.

Note: service.namespace and service.name are not intended to be concatenated for the purpose of forming a single globally unique name for the service. For example the following 2 sets of attributes actually describe 2 different services (despite the fact that the concatenation would result in the same string):

# Resource attributes that describes a service.
namespace = Company.Shop
service.name = shoppingcart
# Another set of resource attributes that describe a different service.
namespace = Company
service.name = Shop.shoppingcart

Telemetry SDK

Status: Stable

type: telemetry.sdk

Description: The telemetry SDK used to capture data recorded by the instrumentation libraries.

Attribute Type Description Examples Requirement Level
telemetry.sdk.language string The language of the telemetry SDK. cpp Required
telemetry.sdk.name string The name of the telemetry SDK as defined above. [1] opentelemetry Required
telemetry.sdk.version string The version string of the telemetry SDK. 1.2.3 Required

[1]: The OpenTelemetry SDK MUST set the telemetry.sdk.name attribute to opentelemetry. If another SDK, like a fork or a vendor-provided implementation, is used, this SDK MUST set the telemetry.sdk.name attribute to the fully-qualified class or module name of this SDK’s main entry point or another suitable identifier depending on the language. The identifier opentelemetry is reserved and MUST NOT be used in this case. All custom identifiers SHOULD be stable across different versions of an implementation.

telemetry.sdk.language 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
cpp cpp
dotnet dotnet
erlang erlang
go go
java java
nodejs nodejs
php php
python python
ruby ruby
rust rust
swift swift
webjs webjs

Telemetry SDK (Experimental)

Status: Experimental

type: telemetry.sdk

Description: Additions to the telemetry SDK.

Attribute Type Description Examples Requirement Level
telemetry.distro.name string The name of the auto instrumentation agent or distribution, if used. [1] parts-unlimited-java Recommended
telemetry.distro.version string The version string of the auto instrumentation agent or distribution, if used. 1.2.3 Recommended

[1]: Official auto instrumentation agents and distributions SHOULD set the telemetry.distro.name attribute to a string starting with opentelemetry-, e.g. opentelemetry-java-instrumentation.

Compute Unit

Status: Experimental

Attributes defining a compute unit (e.g. Container, Process, Function as a Service):

Compute Instance

Status: Experimental

Attributes defining a computing instance (e.g. host):

Environment

Status: Experimental

Attributes defining a running environment (e.g. Operating System, Cloud, Data Center, Deployment Service):

Version attributes

Status: Stable

Version attributes, such as service.version, are values of type string. They are the exact version used to identify an artifact. This may be a semantic version, e.g., 1.2.3, git hash, e.g., 8ae73a, or an arbitrary version string, e.g., 0.1.2.20210101, whatever was used when building the artifact.

Cloud-Provider-Specific Attributes

Status: Experimental

Attributes that are only applicable to resources from a specific cloud provider. Currently, these resources can only be defined for providers listed as a valid cloud.provider in Cloud and below. Provider-specific attributes all reside in the cloud-provider directory. Valid cloud providers are: