Package com.azure.core.util.tracing

Interface Tracer

  • public interface Tracer
    Contract that all tracers must implement to be pluggable into the SDK.
    See Also:
    TracerProxy

    • Field Detail

      • PARENT_SPAN_KEY

        static final String PARENT_SPAN_KEY
        Key for Context which indicates that the context contains parent span data. This span will be used as the parent span for all spans the SDK creates.

        If no span data is listed when the span is created it will default to using this span key as the parent span.

        See Also:
        Constant Field Values

      • USER_SPAN_NAME_KEY

        static final String USER_SPAN_NAME_KEY
        Key for Context which indicates that the context contains the name for the user spans that are created.

        If no span name is listed when the span is created it will default to using the calling method's name.

        See Also:
        Constant Field Values

      • SPAN_CONTEXT_KEY

        static final String SPAN_CONTEXT_KEY
        Key for Context which indicates that the context contains a message span context.
        See Also:
        Constant Field Values

      • DIAGNOSTIC_ID_KEY

        static final String DIAGNOSTIC_ID_KEY
        Key for Context which indicates that the context contains a "Diagnostic Id" for the service call.
        See Also:
        Constant Field Values

      • AZ_TRACING_NAMESPACE_KEY

        static final String AZ_TRACING_NAMESPACE_KEY
        Key for Context which indicates that the context contains the Azure resource provider namespace.
        See Also:
        Constant Field Values

      • SPAN_BUILDER_KEY

        static final String SPAN_BUILDER_KEY
        Key for Context which indicates the shared span builder that is in the current Context.
        See Also:
        Constant Field Values

      • MESSAGE_ENQUEUED_TIME

        static final String MESSAGE_ENQUEUED_TIME
        Key for Context which indicates the time of the last enqueued message in the partition's stream.
        See Also:
        Constant Field Values

      • DISABLE_TRACING_KEY

        static final String DISABLE_TRACING_KEY
        Key for Context which disables tracing for the request associated with the current context.
        See Also:
        Constant Field Values

    • Method Detail

      • start

        Context start​(String methodName,
              Context context)
        Creates a new tracing span.

        The context will be checked for information about a parent span. If a parent span is found, the new span will be added as a child. Otherwise, the parent span will be created and added to the context and any downstream start() calls will use the created span as the parent.

        Code samples

        Starts a tracing span with provided method name and explicit parent span

         // pass the current tracing span context to the calling method
 Context traceContext = new Context(PARENT_SPAN_KEY, "<user-current-span>");
 // start a new tracing span with the given method name and explicit parent span
 Context updatedContext = tracer.start("azure.keyvault.secrets/setsecret", traceContext);
 System.out.printf("Span returned in the context object: %s%n",
     updatedContext.getData(PARENT_SPAN_KEY).get());
        Parameters:
        methodName - Name of the method triggering the span creation.
        context - Additional metadata that is passed through the call stack.
        Returns:
        The updated Context object containing the returned span.
        Throws:
        NullPointerException - if methodName or context is null.

      • start

        default Context start​(String methodName,
                      StartSpanOptions options,
                      Context context)
        Creates a new tracing span.

        The context will be checked for information about a parent span. If a parent span is found, the new span will be added as a child. Otherwise, the parent span will be created and added to the context and any downstream start() calls will use the created span as the parent.

        Code samples

        Starts a tracing span with provided method name and explicit parent span

         // start a new CLIENT tracing span with the given start options and explicit parent span
 StartSpanOptions options = new StartSpanOptions(SpanKind.CLIENT)
     .setAttribute("key", "value");
 Context updatedClientSpanContext = tracer.start("azure.keyvault.secrets/setsecret", options, traceContext);
 System.out.printf("Span returned in the context object: %s%n",
     updatedClientSpanContext.getData(PARENT_SPAN_KEY).get());
        Parameters:
        methodName - Name of the method triggering the span creation.
        options - span creation options.
        context - Additional metadata that is passed through the call stack.
        Returns:
        The updated Context object containing the returned span.
        Throws:
        NullPointerException - if options or context is null.

      • start

        Context start​(String methodName,
              Context context,
              ProcessKind processKind)
        Creates a new tracing span for AMQP calls.

        The context will be checked for information about a parent span. If a parent span is found, the new span will be added as a child. Otherwise, the parent span will be created and added to the context and any downstream start() calls will use the created span as the parent.

        Sets additional request attributes on the created span when processKind is ProcessKind.SEND.

        Returns the diagnostic Id and span context of the returned span when processKind is ProcessKind.MESSAGE.

        Creates a new tracing span with remote parent and returns that scope when the given when processKind is ProcessKind.PROCESS.

        Code samples

        Starts a tracing span with provided method name and AMQP operation SEND

         // pass the current tracing span and request metadata to the calling method
 Context sendContext = new Context(PARENT_SPAN_KEY, "<user-current-span>")
     .addData(ENTITY_PATH_KEY, "entity-path").addData(HOST_NAME_KEY, "hostname");

 // start a new tracing span with explicit parent, sets the request attributes on the span and sets the span
 // kind to client when process kind SEND
 Context updatedSendContext = tracer.start("azure.eventhubs.send", sendContext, ProcessKind.SEND);
 System.out.printf("Span returned in the context object: %s%n",
     updatedSendContext.getData(PARENT_SPAN_KEY).get());

        Starts a tracing span with provided method name and AMQP operation MESSAGE

         String diagnosticIdKey = "Diagnostic-Id";
 // start a new tracing span with explicit parent, sets the diagnostic Id (traceparent headers) on the current
 // context when process kind MESSAGE
 Context updatedReceiveContext = tracer.start("azure.eventhubs.receive", traceContext,
     ProcessKind.MESSAGE);
 System.out.printf("Diagnostic Id: %s%n", updatedReceiveContext.getData(diagnosticIdKey).get().toString());

        Starts a tracing span with provided method name and AMQP operation PROCESS

         String spanImplContext = "span-context";
 // start a new tracing span with remote parent and uses the span in the current context to return a scope
 // when process kind PROCESS
 Context processContext = new Context(PARENT_SPAN_KEY, "<user-current-span>")
     .addData(spanImplContext, "<user-current-span-context>");
 Context updatedProcessContext = tracer.start("azure.eventhubs.process", processContext,
     ProcessKind.PROCESS);
 System.out.printf("Scope: %s%n", updatedProcessContext.getData("scope").get());
        Parameters:
        methodName - Name of the method triggering the span creation.
        context - Additional metadata that is passed through the call stack.
        processKind - AMQP operation kind.
        Returns:
        The updated Context object containing the returned span.
        Throws:
        NullPointerException - if methodName or context or processKind is null.

      • end

        void end​(int responseCode,
         Throwable error,
         Context context)
        Completes the current tracing span.

        Code samples

        Completes the tracing span present in the context, with the corresponding OpenTelemetry status for the given response status code

         // context containing the current tracing span to end
 String openTelemetrySpanKey = "openTelemetry-span";
 Context traceContext = new Context(PARENT_SPAN_KEY, "<user-current-span>");

 // completes the tracing span with the passed response status code
 tracer.end(200, null, traceContext);
        Parameters:
        responseCode - Response status code if the span is in an HTTP call context.
        error - Throwable that happened during the span or null if no exception occurred.
        context - Additional metadata that is passed through the call stack.
        Throws:
        NullPointerException - if context is null.

      • end

        void end​(String statusMessage,
         Throwable error,
         Context context)
        Completes the current tracing span for AMQP calls.

        Code samples

        Completes the tracing span with the corresponding OpenTelemetry status for the given status message

         // context containing the current tracing span to end
 // completes the tracing span with the passed status message
 tracer.end("success", null, traceContext);
        Parameters:
        statusMessage - The error or success message that occurred during the call, or null if no error occurred.
        error - Throwable that happened during the span or null if no exception occurred.
        context - Additional metadata that is passed through the call stack.
        Throws:
        NullPointerException - if context is null.

      • setAttribute

        void setAttribute​(String key,
                  String value,
                  Context context)
        Adds metadata to the current span. If no span information is found in the context, then no metadata is added.
        Parameters:
        key - Name of the metadata.
        value - Value of the metadata.
        context - Additional metadata that is passed through the call stack.
        Throws:
        NullPointerException - if key or value or context is null.

      • setSpanName

        Context setSpanName​(String spanName,
                    Context context)
        Sets the name for spans that are created.

        Code samples

        Retrieve the span name of the returned span

         // Sets the span name of the returned span on the context object, with key PARENT_SPAN_KEY
 String openTelemetrySpanKey = "openTelemetry-span";
 Context context = tracer.setSpanName("test-span-method", Context.NONE);
 System.out.printf("Span name: %s%n", context.getData(PARENT_SPAN_KEY).get().toString());
        Parameters:
        spanName - Name to give the next span.
        context - Additional metadata that is passed through the call stack.
        Returns:
        The updated Context object containing the name of the returned span.
        Throws:
        NullPointerException - if spanName or context is null.

      • addLink

        void addLink​(Context context)
        Provides a way to link multiple tracing spans. Used in batching operations to relate multiple requests under a single batch.

        Code samples

        Link multiple spans using their span context information

         // use the parent context containing the current tracing span to start a child span
 Context parentContext = new Context(PARENT_SPAN_KEY, "<user-current-span>");
 // use the returned span context information of the current tracing span to link
 Context spanContext = tracer.start("test.method", parentContext, ProcessKind.MESSAGE);

 // Adds a link between multiple span's using the span context information of the Span
 // For each event processed, add a link with the created spanContext
 tracer.addLink(spanContext);
        Parameters:
        context - Additional metadata that is passed through the call stack.
        Throws:
        NullPointerException - if context is null.

      • extractContext

        Context extractContext​(String diagnosticId,
                       Context context)
        Extracts the span's context as Context from upstream.

        Code samples

        Extracts the corresponding span context information from a valid diagnostic id

         // Extracts the span context information from the passed diagnostic Id that can be used for linking spans.
 String spanImplContext = "span-context";
 Context spanContext = tracer.extractContext("valid-diagnostic-id", Context.NONE);
 System.out.printf("Span context of the current tracing span: %s%n", spanContext.getData(spanImplContext).get());
        Parameters:
        diagnosticId - Unique identifier for the trace information of the span.
        context - Additional metadata that is passed through the call stack.
        Returns:
        The updated Context object containing the span context.
        Throws:
        NullPointerException - if diagnosticId or context is null.

      • getSharedSpanBuilder

        default Context getSharedSpanBuilder​(String spanName,
                                     Context context)
        Returns a span builder with the provided name in Context.

        Code samples

        Returns a builder with the provided span name.

         // Returns a span builder with the provided name
 String methodName = "message-span";
 Context spanContext = tracer.getSharedSpanBuilder(methodName, Context.NONE);
 System.out.printf("Span context of the current tracing span: %s%n", spanContext.getData(SPAN_BUILDER_KEY).get());
        Parameters:
        spanName - Name to give the span for the created builder.
        context - Additional metadata that is passed through the call stack.
        Returns:
        The updated Context object containing the span builder.
        Throws:
        NullPointerException - if context or spanName is null.

      • addEvent

        @Deprecated
default void addEvent​(String name,
                      Map<String,​Object> attributes,
                      OffsetDateTime timestamp)
        Deprecated.
        Use addEvent(String, Map, OffsetDateTime, Context)
        Adds an event to the current span with the provided timestamp and attributes.

        This API does not provide any normalization if provided timestamps are out of range of the current span timeline

        Supported attribute values include String, double, boolean, long, String [], double [], long []. Any other Object value type and null values will be silently ignored.

        Parameters:
        name - the name of the event.
        attributes - the additional attributes to be set for the event.
        timestamp - The instant, in UTC, at which the event will be associated to the span.
        Throws:
        NullPointerException - if eventName is null.

      • addEvent

        default void addEvent​(String name,
                      Map<String,​Object> attributes,
                      OffsetDateTime timestamp,
                      Context context)
        Adds an event to the span present in the Context with the provided timestamp and attributes.

        This API does not provide any normalization if provided timestamps are out of range of the current span timeline

        Supported attribute values include String, double, boolean, long, String [], double [], long []. Any other Object value type and null values will be silently ignored.

        Parameters:
        name - the name of the event.
        attributes - the additional attributes to be set for the event.
        timestamp - The instant, in UTC, at which the event will be associated to the span.
        context - the call metadata containing information of the span to which the event should be associated with.
        Throws:
        NullPointerException - if eventName is null.

      • makeSpanCurrent

        default AutoCloseable makeSpanCurrent​(Context context)
        Makes span current. Implementations may put it on ThreadLocal. Make sure to always use try-with-resource statement with makeSpanCurrent
        Parameters:
        context - Context with span.

        Code samples

        Starts a tracing span, makes it current and ends it

         // Starts a span, makes it current and then stops it.
 Context traceContext = tracer.start("EventHub.process", Context.NONE);

 // Make sure to always use try-with-resource statement with makeSpanCurrent
 try (AutoCloseable ignored = tracer.makeSpanCurrent(traceContext)) {
     System.out.println("doing some work...");
 } catch (Throwable throwable) {
     tracer.end("Failure", throwable, traceContext);
 } finally {
     tracer.end("OK", null, traceContext);
 }
        Returns:
        Closeable that should be closed in the same thread with try-with-resource statement.