The core of the tracing implementation for Che is in the che-core-tracing-core and che-core-tracing-web modules.
All HTTP requests to the tracing API have their own trace. This is done by TracingFilter from the OpenTracing library, which is bound for the whole server application. Adding a @Traced annotation to methods causes the TracingInterceptor to add tracing spans for them.
Tagging
Spans may contain standard tags, such as operation name, span origin, error, as well as others that may help users with querying and filtering spans. Workspace-related operations (such as starting or stopping workspaces) have additional tags, including userId, workspaceId, and stackId. Spans created by TracingFilter also have an HTTP status code tag.
Declaring tags in a traced method is done statically by setting fields from the TracingTags class:
TracingTags.WORKSPACE_ID.set(workspace.getId());TracingTags is a class where all commonly used tags are declared, as respective AnnotationAware tag implementations.
For more information about how to use Jaeger UI, visit Jaeger documentation: Jaeger Getting Started Guide.