Documentation
¶
Overview ¶
Package nethttp provides OpenTracing instrumentation for the net/http package.
Index ¶
- func Middleware(tr opentracing.Tracer, h http.Handler, options ...MWOption) http.Handler
- func MiddlewareFunc(tr opentracing.Tracer, h http.HandlerFunc, options ...MWOption) http.HandlerFunc
- type ClientOption
- type MWOption
- func MWComponentName(componentName string) MWOption
- func MWSpanFilter(f func(r *http.Request) bool) MWOption
- func MWSpanObserver(f func(span opentracing.Span, r *http.Request)) MWOption
- func MWURLTagFunc(f func(u *url.URL) string) MWOption
- func OperationNameFunc(f func(r *http.Request) string) MWOption
- type Tracer
- type Transport
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
func Middleware ¶
Middleware wraps an http.Handler and traces incoming requests. Additionally, it adds the span to the request's context.
By default, the operation name of the spans is set to "HTTP {method}". This can be overriden with options.
Example:
http.ListenAndServe("localhost:80", nethttp.Middleware(tracer, http.DefaultServeMux))
The options allow fine tuning the behavior of the middleware.
Example:
mw := nethttp.Middleware(
tracer,
http.DefaultServeMux,
nethttp.OperationNameFunc(func(r *http.Request) string {
return "HTTP " + r.Method + ":/api/customers"
}),
nethttp.MWSpanObserver(func(sp opentracing.Span, r *http.Request) {
sp.SetTag("http.uri", r.URL.EscapedPath())
}),
)
func MiddlewareFunc ¶
func MiddlewareFunc(tr opentracing.Tracer, h http.HandlerFunc, options ...MWOption) http.HandlerFunc
MiddlewareFunc wraps an http.HandlerFunc and traces incoming requests. It behaves identically to the Middleware function above.
Example:
http.ListenAndServe("localhost:80", nethttp.MiddlewareFunc(tracer, MyHandler))
Types ¶
type ClientOption ¶
type ClientOption func(*clientOptions)
ClientOption contols the behavior of TraceRequest.
func ClientSpanObserver ¶
func ClientSpanObserver(f func(span opentracing.Span, r *http.Request)) ClientOption
ClientSpanObserver returns a ClientOption that observes the span for the client-side span.
func ClientTrace ¶
func ClientTrace(enabled bool) ClientOption
ClientTrace returns a ClientOption that turns on or off extra instrumentation via httptrace.WithClientTrace.
func ComponentName ¶
func ComponentName(componentName string) ClientOption
ComponentName returns a ClientOption that sets the component name for the client-side span.
func OperationName ¶
func OperationName(operationName string) ClientOption
OperationName returns a ClientOption that sets the operation name for the client-side span.
type MWOption ¶
type MWOption func(*mwOptions)
MWOption controls the behavior of the Middleware.
func MWComponentName ¶
MWComponentName returns a MWOption that sets the component name for the server-side span.
func MWSpanFilter ¶
MWSpanFilter returns a MWOption that filters requests from creating a span for the server-side span. Span won't be created if it returns false.
func MWSpanObserver ¶
func MWSpanObserver(f func(span opentracing.Span, r *http.Request)) MWOption
MWSpanObserver returns a MWOption that observe the span for the server-side span.
func MWURLTagFunc ¶
MWURLTagFunc returns a MWOption that uses given function f to set the span's http.url tag. Can be used to change the default http.url tag, eg to redact sensitive information.
type Tracer ¶
type Tracer struct {
// contains filtered or unexported fields
}
Tracer holds tracing details for one HTTP request.
func TraceRequest ¶
func TraceRequest(tr opentracing.Tracer, req *http.Request, options ...ClientOption) (*http.Request, *Tracer)
TraceRequest adds a ClientTracer to req, tracing the request and all requests caused due to redirects. When tracing requests this way you must also use Transport.
Example:
func AskGoogle(ctx context.Context) error {
client := &http.Client{Transport: &nethttp.Transport{}}
req, err := http.NewRequest("GET", "http://google.com", nil)
if err != nil {
return err
}
req = req.WithContext(ctx) // extend existing trace, if any
req, ht := nethttp.TraceRequest(tracer, req)
defer ht.Finish()
res, err := client.Do(req)
if err != nil {
return err
}
res.Body.Close()
return nil
}
func TracerFromRequest ¶
TracerFromRequest retrieves the Tracer from the request. If the request does not have a Tracer it will return nil.
func (*Tracer) Span ¶
func (h *Tracer) Span() opentracing.Span
Span returns the root span of the traced request. This function should only be called after the request has been executed.
type Transport ¶
type Transport struct {
// The actual RoundTripper to use for the request. A nil
// RoundTripper defaults to http.DefaultTransport.
http.RoundTripper
}
Transport wraps a RoundTripper. If a request is being traced with Tracer, Transport will inject the current span into the headers, and set HTTP related tags on the span.
Source Files