agent-features.md 2.4 KB
OpenTelemetry Java Agent Features
This lists out some of the features specific to java agents that OpenTelemetry Auto Instrumentation provides.
- Bundled exporters
- OTLP
- Jaeger gRPC
- Logging
- Zipkin
- Bundled propagators
- Environment variable configuration as per spec
- Additional support for system properties for same variables by transforming UPPER_UNDERSCORE -> lower.dot
- Ability to disable individual instrumentation, or only enable certain ones.
- Ability to load a custom exporter via an external JAR library
- Isolation from application
- Separate Agent class loader with almost all agent-specific classes
- OpenTelemetry SDK initialized in Agent class loader
- Shading of instrumentation libraries when used in agent
- API bridge for application usage of API to access the Agent class loader's SDK
- API bridge not applied if user brings incompatible API version, preventing linkage errors (similar to safety mechanism below)
- Safety mechanisms to prevent application linkage errors
- Collect all references from instrumentation to library and only apply instrumentation if they exist in application
- Verify above at compile time
- Instrumentation tests that run the java agent in a near-production configuration
- Ability to run tests against a fixed version and the latest version of dependencies
- Docker-based smoke tests to verify agent behavior across JVM runtimes, Java application servers
- Ability to create custom distributions, agents with different components / configuration
- Can set different defaults for properties
- Can customize tracer configuration programmatically
- Can provide custom exporter, propagator, sampler
- Can hook into bytebuddy to customize bytecode manipulation
- Noteworthy instrumentation
- Log injection of IDs (logback, log4j2, log4j)
- Automatic context propagation across
Executors - Ability to instrument methods in the application if user adds
@WithSpanannotation