Language APIs & SDKs

OpenTelemetry code instrumentation is supported for many popular programming languages

  1. OpenTelemetry code instrumentation is supported for the languages listed in the Statuses and Releases table below.
  2. For Go, .NET, PHP, Python, Java and JavaScript you can use zero-code solutions to add instrumentation to your application without code changes.
  3. If you are using Kubernetes, you can use the OpenTelemetry Operator for Kubernetes to inject these zero-code solutions into your application.

Status and Releases

Language Traces Metrics Logs
C++ Stable Stable Stable
C#/.NET Stable Stable Stable
Go Stable Stable Beta
Java Stable Stable Stable
JavaScript Stable Stable Development
Python Stable Stable Development

SDK Configuration

  1. OpenTelemetry SDKs support configuration in each language and with environment variables.
  2. Values set with environment variables override equivalent configuration in code using SDK APIs.

General

Support for environment variables is optional.

OTEL_SERVICE_NAME

  1. Sets the value of the service.name resource attribute.
  2. Default value - unknown_service
  3. If service.name is also provided in OTEL_RESOURCE_ATTRIBUTES, then OTEL_SERVICE_NAME takes precedence.
  4. export OTEL_SERVICE_NAME=”your-service-name”

OTEL_RESOURCE_ATTRIBUTES

  1. Key-value pairs to be used as resource attributes. See Resource SDK for more details.
  2. Default value - Empty
  3. export OTEL_RESOURCE_ATTRIBUTES=”key1=value1,key2=value2”

OTEL_TRACES_SAMPLER

  1. Specifies the Sampler used to sample traces by the SDK.
  2. Default value - parentbased_always_on
  3. export OTEL_TRACES_SAMPLER=”traceidratio”

Accepted values for OTEL_TRACES_SAMPLER are:

Sampler Desc
always_on AlwaysOnSampler
always_off AlwaysOffSampler
traceidratio TraceIdRatioBased
parentbased_always_on ParentBased(root=AlwaysOnSampler)
parentbased_always_off ParentBased(root=AlwaysOffSampler)
parentbased_traceidratio ParentBased(root=TraceIdRatioBased)
parentbased_jaeger_remote ParentBased(root=JaegerRemoteSampler)
jaeger_remote JaegerRemoteSampler
xray AWS X-Ray Centralized Sampling (third party)

OTEL_TRACES_SAMPLER_ARG

  1. Specifies arguments, if applicable, to the sampler defined in by OTEL_TRACES_SAMPLER.
  2. The specified value will only be used if OTEL_TRACES_SAMPLER is set.
  3. Each Sampler type defines its own expected input, if any.
  4. Invalid or unrecognized input is logged as an error.
  5. Default value - Empty
1
2
export OTEL_TRACES_SAMPLER="traceidratio"
export OTEL_TRACES_SAMPLER_ARG="0.5"

Depending on the value of OTEL_TRACES_SAMPLER, OTEL_TRACES_SAMPLER_ARG may be set as follows:

  1. For traceidratio and parentbased_traceidratio samplers: Sampling probability, a number in the [0..1] range, e.g. “0.25”. - Default is 1.0 if unset.

OTEL_PROPAGATORS

  1. Specifies Propagators to be used in a comma-separated list.
  2. Default value - tracecontext,baggage
  3. export OTEL_PROPAGATORS=”b3”

Accepted values for OTEL_PROPAGATORS are:

Propagator Desc
tracecontext W3C Trace Context
baggage W3C Baggage
b3 B3 Single
b3multi B3 Multi
jaeger Jaeger
xray AWS X-Ray
ottrace OT Trace
none No automatically configured propagator.

OTEL_TRACES_EXPORTER

  1. Specifies which exporter is used for traces. Depending on the implementation it may be a comma-separated list.
  2. Default value - otlp
  3. export OTEL_TRACES_EXPORTER=”jaeger”

Accepted values for are:

Exporter Desc
otlp OTLP
jaeger export in Jaeger data model
zipkin Zipkin
console Standard Output
none No automatically configured exporter for traces.

OTEL_METRICS_EXPORTER

  1. Specifies which exporter is used for metrics. Depending on the implementation it may be a comma-separated list.
  2. Default value - otlp
  3. export OTEL_METRICS_EXPORTER=”prometheus”

Accepted values for OTEL_METRICS_EXPORTER are:

Exporter Desc
otlp OTLP
prometheus Prometheus
console Standard Output
none No automatically configured exporter for metrics.

OTEL_LOGS_EXPORTER

  1. Specifies which exporter is used for logs. Depending on the implementation it may be a comma-separated list.
  2. Default value - otlp
  3. export OTEL_LOGS_EXPORTER=”otlp”

Accepted values for OTEL_LOGS_EXPORTER are:

Exporter Desc
otlp OTLP
console Standard Output
none No automatically configured exporter for logs.

OTLP Exporter

Endpoint Configuration

The following environment variables let you configure an OTLP/gRPC or OTLP/HTTP endpoint for your traces, metrics, and logs.

OTEL_EXPORTER_OTLP_ENDPOINT

  1. A base endpoint URL for any signal type, with an optionally-specified port number.

  2. Helpful for when you’re sending more than one signal to the same endpoint and want one environment variable to control the endpoint.

  3. Default value

  4. Example

  5. For OTLP/HTTP, exporters in the SDK construct signal-specific URLs when this environment variable is set.

OTEL_EXPORTER_OTLP_TRACES_ENDPOINT
  1. Endpoint URL for trace data only, with an optionally-specified port number. Typically ends with v1/traces when using OTLP/HTTP.
  2. Default value
  3. Example
OTEL_EXPORTER_OTLP_METRICS_ENDPOINT
  1. Endpoint URL for metric data only, with an optionally-specified port number. Typically ends with v1/metrics when using OTLP/HTTP.
  2. Default value
  3. Example
OTEL_EXPORTER_OTLP_LOGS_ENDPOINT
  1. Endpoint URL for log data only, with an optionally-specified port number. Typically ends with v1/logs when using OTLP/HTTP.
  2. Default value
  3. Example

Header configuration

The following environment variables let you configure additional headers as a list of key-value pairs to add in outgoing gRPC or HTTP requests.

OTEL_EXPORTER_OTLP_HEADERS
  1. A list of headers to apply to all outgoing data (traces, metrics, and logs).
  2. Default value - N/A
  3. export OTEL_EXPORTER_OTLP_HEADERS=”api-key=key,other-config-value=value”
OTEL_EXPORTER_OTLP_TRACES_HEADERS
  1. A list of headers to apply to all outgoing traces.
  2. Default value - N/A
  3. export OTEL_EXPORTER_OTLP_TRACES_HEADERS=”api-key=key,other-config-value=value”
OTEL_EXPORTER_OTLP_METRICS_HEADERS
  1. A list of headers to apply to all outgoing metrics.
  2. Default value - N/A
  3. export OTEL_EXPORTER_OTLP_METRICS_HEADERS=”api-key=key,other-config-value=value”
OTEL_EXPORTER_OTLP_LOGS_HEADERS
  1. A list of headers to apply to all outgoing logs.
  2. Default value - N/A
  3. export OTEL_EXPORTER_OTLP_LOGS_HEADERS=”api-key=key,other-config-value=value”

Timeout Configuration

configure the maximum time (in milliseconds) an OTLP Exporter will wait before transmitting the net batch of data.

OTEL_EXPORTER_OTLP_TIMEOUT
  1. The timeout value for all outgoing data (traces, metrics, and logs) in milliseconds.
  2. Default value - 10000 - 10s
  3. export OTEL_EXPORTER_OTLP_TIMEOUT=500
OTEL_EXPORTER_OTLP_TRACES_TIMEOUT
  1. The timeout value for all outgoing traces in milliseconds.
  2. Default value - 10000 - 10s
  3. export OTEL_EXPORTER_OTLP_TRACES_TIMEOUT=500
OTEL_EXPORTER_OTLP_METRICS_TIMEOUT
  1. The timeout value for all outgoing metrics in milliseconds.
  2. Default value - 10000 - 10s
  3. export OTEL_EXPORTER_OTLP_METRICS_TIMEOUT=500
OTEL_EXPORTER_OTLP_LOGS_TIMEOUT
  1. The timeout value for all outgoing logs in milliseconds.
  2. Default value - 10000 - 10s
  3. export OTEL_EXPORTER_OTLP_LOGS_TIMEOUT=500

Protocol configuration

The following environment variables configure the OTLP transport protocol an OTLP exporter uses.

OTEL_EXPORTER_OTLP_PROTOCOL
  1. Specifies the OTLP transport protocol to be used for all telemetry data.
  2. Default value - SDK-dependent, but will typically be either http/protobuf or grpc.
  3. export OTEL_EXPORTER_OTLP_PROTOCOL=grpc

Valid values are:

Transport protocol Desc
grpc OTLP/gRPC
http/protobuf OTLP/HTTP + protobuf
http/json OTLP/HTTP + JSON
OTEL_EXPORTER_OTLP_TRACES_PROTOCOL

Specifies the OTLP transport protocol to be used for trace data.

OTEL_EXPORTER_OTLP_METRICS_PROTOCOL

Specifies the OTLP transport protocol to be used for metrics data.

OTEL_EXPORTER_OTLP_LOGS_PROTOCOL

Specifies the OTLP transport protocol to be used for log data.