Client Library Features

Version 1.62 Go to the latest 1.x version Go to the latest 2.x version

Jaeger clients have been retired. Please refer to this notice.

The table below provides a feature matrix for the existing client libraries. Cells marked with ? indicate that it’s not known if the given client supports the given feature and additional research & documentation update is required.

The table is auto-generated from data/clients.yaml

Data format and transport for reporting spans to Jaeger backend
Feature	Go	Java	Node.js	Python	C++	C#
Report `jaeger.thrift` , Compact protocol, over UDP	✅	✅	❌	✅	✅	✅
Report `jaeger.thrift` , Binary protocol, over UDP	❌	❌	✅	❌	❌	❌
Report `jaeger.thrift` , Binary protocol, over TCP (HTTP)	✅	✅	✅	❌	✅	✅
Report Zipkin Thrift, Binary protocol, over TCP (HTTP)	✅	✅	❌	❌	❌	❌
Inter-process propagation wire format (headers)
Feature	Go	Java	Node.js	Python	C++	C#
Uber’s original headers	✅	✅	✅	✅	✅	✅
Zipkin’s B3 headers	✅	✅	✅	✅	❌	✅
W3C Trace Context headers	coming	✅	coming	coming	coming	coming
Support inbound `jaeger-debug-id` header	when there is no trace	when there is no trace	❔	✅	❔	when there is no trace
Accept baggage from `jaeger-baggage` headers	when there is no trace	❌	❔	✅	❔	❌
Support for 128bit Trace ID	✅	✅	✅	✅	✅	✅
Metrics
Feature	Go	Java	Node.js	Python	C++	C#
Support standard tracer metrics (number of spans started, finished, reported, etc.)	✅	✅	✅	✅	❔	✅
Support standard RPC metrics	✅	❌	❌	❌	❌	❌
Metrics in Prometheus format	✅	✅	❌	✅	❔	❔
Tracer configuration
Feature	Go	Java	Node.js	Python	C++	C#
Support declarative tracer configuration	✅	✅	✅	✅	❔	✅
Allow configuring tracer tags, aka process tags	✅	✅	✅	✅	❔	✅
Allow remote configuration of samplers	✅	✅	✅	✅	✅	✅
Remotely configurable per-endpoint sampler	✅	✅	✅	✅	✅	✅
Remotely configurable baggage restrictions	✅	coming	coming	coming	❌	coming
Tracer configuration via environment variables
Feature	Go	Java	Node.js	Python	C++	C#
`JAEGER_SERVICE_NAME` defines service name that will be associated with the emitted spans.	✅	✅	✅	❌	✅	✅
`JAEGER_TAGS` defines a comma-separated list of static tags, aka “tracer tags”, e.g. `hostname=foobar,my.app.version=1.2.3`. These tags are added as the `Process` tags to each span.	✅	✅	✅	✅	✅	✅
`JAEGER_DISABLED` (not recommended) when set to true, instructs the Configuration to return a no-op tracer. Neither trace/span IDs nor baggage will be propagated with a no-op tracer. Instead of disabling the tracer completely, use `const` sampler with `0` param, which will minimize the overhead but keep the propagation going.	✅	❌	✅	❌	✅	❌
`JAEGER_AGENT_HOST` defines hostname for reporting spans over UDP/Thrift. To avoid packet loss, the agent is expected to run on the same machine as the application. This var is useful when there are multiple networking namespaces on the host.	✅	✅	✅	✅	✅	✅
`JAEGER_AGENT_PORT` defines port for reporting spans over UDP/Thrift.	✅	✅	✅	✅	✅	✅
`JAEGER_ENDPOINT` defines the URL for reporting spans via HTTP/Thrift. This setting allows for a deployment mode where spans are submitted directly to the collector.	✅	✅	✅	❌	✅	✅
`JAEGER_AUTH_TOKEN` defines an optional auth token when reporting over HTTP.	❌	✅	❌	❌	❌	✅
`JAEGER_USER` can be used for basic authentication when reporting over HTTP.	✅	✅	✅	❌	❌	✅
`JAEGER_PASSWORD` can be used for basic authentication when using reporting over HTTP.	✅	✅	✅	❌	❌	✅
`JAEGER_REPORTER_LOG_SPANS` instructs the Reporter to log finished span IDs. The reporter may need to be given a Logger for this option to take effect.	✅	✅	✅	❌	✅	✅
`JAEGER_REPORTER_MAX_QUEUE_SIZE` defines the max size of the in-memory buffer used to keep spans before they are sent out.	✅	✅	❌	❌	✅	✅
`JAEGER_REPORTER_FLUSH_INTERVAL` defines how frequently the report flushes span batches. Reporter can also flush the batch if the batch size reaches the maximum UDP packet size (~64Kb).	✅	✅	✅	❌	✅	✅
`JAEGER_SAMPLER_TYPE` defines the type of sampler to use, e.g. `probabilistic`, or `const` (see Sampling).	✅	✅	✅	❌	✅	✅
`JAEGER_SAMPLER_PARAM` provides configuration value to the sampler, e.g. `probability=0.001` (see Sampling).	✅	✅	✅	❌	✅	✅
`JAEGER_SAMPLER_MANAGER_HOST_PORT` defines the address of HTTP server that services client configuration, such as sampling strategies, baggage restrictions, throttling config, etc. The variable name is a legacy misnomer from the time when the server only provided the sampling strategies. At the moment only `jaeger-agent` implements this REST API.	✅	✅	✅	❌	✅	✅
`JAEGER_SAMPLER_REFRESH_INTERVAL` defines how often the sampler polls the config server for updates to the sampling strategies.	✅	❌	✅	❌	❌	❌
`JAEGER_SAMPLER_MAX_OPERATIONS` instructs the adaptive sampler to limit how many distinct operation names the sampler will track, to avoid unbound memory usage.	✅	❌	❌	❌	❌	❌
`JAEGER_PROPAGATION` defines the propagation format used by the tracer. Supported values are `jaeger` (defined here), `b3` (defined here ) and `w3c` (defined here )	❌	✅	❌	❌	❌	✅
`JAEGER_TRACEID_128BIT` if true, instructs the tracer to generate 128bit trace IDs instead of the default 64bit. In the future 128bit will become the default.	✅	✅	❌	✅	❌	✅
`JAEGER_RPC_METRICS` when true, enables additional generation of RPC metrics from the tracing instrumentation. This is an experimental feature in the Go client. See also https://github.com/opentracing-contrib/java-metrics .	✅	❌	❌	❌	❌	❌