io.opencensus.contrib.http

Class HttpServerHandler<Q,P,C>

java.lang.Object

io.opencensus.contrib.http.HttpServerHandler<Q,P,C>

Type Parameters:

Q - the HTTP request entity.

P - the HTTP response entity.

C - the type of the carrier.

@ExperimentalApi
public class HttpServerHandler<Q,P,C>
extends Object

This helper class provides routine methods to instrument HTTP servers.

Since:

0.19

Constructor Summary

Constructors

Constructor and Description
HttpServerHandler(io.opencensus.trace.Tracer tracer, HttpExtractor<Q,P> extractor, io.opencensus.trace.propagation.TextFormat textFormat, io.opencensus.trace.propagation.TextFormat.Getter<C> getter, Boolean publicEndpoint) Creates a HttpServerHandler with given parameters.

Method Summary

Modifier and Type	Method and Description
io.opencensus.trace.Span	getSpanFromContext(HttpRequestContext context) Retrieves Span from the HttpRequestContext.
void	handleEnd(HttpRequestContext context, Q request, P response, Throwable error) Close an HTTP span and records stats specific to the request.
void	handleMessageReceived(HttpRequestContext context, long bytes) Instrument an HTTP span after a message is received.
void	handleMessageSent(HttpRequestContext context, long bytes) Instrument an HTTP span after a message is sent.
HttpRequestContext	handleStart(C carrier, Q request) Instrument an incoming request before it is handled.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

HttpServerHandler

public HttpServerHandler(io.opencensus.trace.Tracer tracer,
                         HttpExtractor<Q,P> extractor,
                         io.opencensus.trace.propagation.TextFormat textFormat,
                         io.opencensus.trace.propagation.TextFormat.Getter<C> getter,
                         Boolean publicEndpoint)

Creates a HttpServerHandler 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.

getter - the getter used when extracting information from the carrier.

publicEndpoint - set to true for publicly accessible HTTP(S) server. If true then incoming tracecontext will be added as a link instead of as a parent.

Since:

0.19

Method Detail

handleStart

public HttpRequestContext handleStart(C carrier,
                                      Q request)

Instrument an incoming request before it is handled.

This method will create a span under the deserialized propagated parent context. If the parent context is not present, the span will be created under the current context.

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

Parameters:

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,
                      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 message events for the span and record measurements associated with the request.

Parameters:

context - the HttpRequestContext used with handleStart(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 io.opencensus.trace.Span getSpanFromContext(HttpRequestContext context)

Retrieves Span from the HttpRequestContext.

Parameters:

context - request specific HttpRequestContext

Returns:

Span associated with the request.

Since:

0.19