middleware

Documentation

Overview

Package middleware provides some usable transport middleware to deal with propagating Zipkin traces across service boundaries.

Index

• type HandlerFunc
  • func FromHTTPRequest(tracer opentracing.Tracer, operationName string) HandlerFunc
• type RequestFunc
  • func ToHTTPRequest(tracer opentracing.Tracer) RequestFunc

Types

type HandlerFunc

type HandlerFunc func(next http.Handler) http.Handler

HandlerFunc is a middleware function for incoming HTTP requests.

func FromHTTPRequest

func FromHTTPRequest(tracer opentracing.Tracer, operationName string,
) HandlerFunc

FromHTTPRequest returns a Middleware HandlerFunc that tries to join with an OpenTracing trace found in the HTTP request headers and starts a new Span called `operationName`. If no trace could be found in the HTTP request headers, the Span will be a trace root. The Span is incorporated in the HTTP Context object and can be retrieved with opentracing.SpanFromContext(ctx).

type RequestFunc

type RequestFunc func(req *http.Request) *http.Request

RequestFunc is a middleware function for outgoing HTTP requests.

func ToHTTPRequest

func ToHTTPRequest(tracer opentracing.Tracer) RequestFunc

ToHTTPRequest returns a RequestFunc that injects an OpenTracing Span found in context into the HTTP Headers. If no such Span can be found, the RequestFunc is a noop.