Class HttpClientHandler<Q,P,C>

java.lang.Object
io.opencensus.contrib.http.HttpClientHandler<Q,P,C>
Type Parameters:
Q - the HTTP request entity.
P - the HTTP response entity.
C - the type of the carrier.
@ExperimentalApi public class HttpClientHandler<Q,P,C> extends Object
This helper class provides routine methods to instrument HTTP clients.
Since:
0.19

  • Constructor Details

    • HttpClientHandler

      public HttpClientHandler(Tracer tracer, HttpExtractor<Q,P> extractor, TextFormat textFormat, TextFormat.Setter<C> setter)
      Creates a HttpClientHandler with given parameters.
      Parameters:
      tracer - the Open Census tracing component.
      extractor - the HttpExtractor used to extract information from the request/response.
      textFormat - the TextFormat used in HTTP propagation.
      setter - the setter used when injecting information to the carrier.
      Since:
      0.19

  • Method Details

    • handleStart

      public HttpRequestContext handleStart(@Nullable Span parent, C carrier, Q request)
      Instrument a request for tracing and stats before it is sent.

      This method will create a span in current context to represent the HTTP call. The created span will be serialized and propagated to the server.

      The generated span will NOT be set as current context. User can control when to enter the scope of this span. Use AbstractHttpHandler.getSpanFromContext(HttpRequestContext) to retrieve the span.

      Parameters:
      parent - the parent Span. null indicates using current span.
      carrier - the entity that holds the HTTP information.
      request - the request entity.
      Returns:
      the HttpRequestContext that contains stats and trace data associated with the request.
      Since:
      0.19

    • handleEnd

      public void handleEnd(HttpRequestContext context, @Nullable Q request, @Nullable P response, @Nullable Throwable error)
      Close an HTTP span and records stats specific to the request.

      This method will set status of the span and end it. Additionally it will record measurements associated with the request.

      Parameters:
      context - the HttpRequestContext returned from handleStart(Span, Object, Object)
      request - the HTTP request entity.
      response - the HTTP response entity. null means invalid response.
      error - the error occurs when processing the response.
      Since:
      0.19

    • handleMessageSent

      public final void handleMessageSent(HttpRequestContext context, long bytes)
      Instrument an HTTP span after a message is sent. Typically called for every chunk of request or response is sent.
      Parameters:
      context - request specific HttpRequestContext
      bytes - bytes sent.
      Since:
      0.19

    • handleMessageReceived

      public final void handleMessageReceived(HttpRequestContext context, long bytes)
      Instrument an HTTP span after a message is received. Typically called for every chunk of request or response is received.
      Parameters:
      context - request specific HttpRequestContext
      bytes - bytes received.
      Since:
      0.19

    • getSpanFromContext

      public Span getSpanFromContext(HttpRequestContext context)
      Retrieves Span from the HttpRequestContext.
      Parameters:
      context - request specific HttpRequestContext
      Returns:
      Span associated with the request.
      Since:
      0.19