splunkhttp

README

Splunk specific instrumentation for net/http

Example

Simplified example:

package main

import (
	"net/http"

	"github.com/signalfx/splunk-otel-go/distro"
	"github.com/signalfx/splunk-otel-go/instrumentation/net/http/splunkhttp"
	"go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp"
)

func main() {
	distro.Run()

	var handler http.Handler = http.HandlerFunc(
		func(w http.ResponseWriter, r *http.Request) {
			w.Write([]byte("Hello"))
		}
	)
	handler = splunkhttp.NewHandler(handler)
	handler = otelhttp.NewHandler(handler, "my-service")

	http.ListenAndServe(":9090", handler)
}

Configuration

Splunk distribution configuration

Environment variable	Default value	Purpose
SPLUNK_TRACE_RESPONSE_HEADER_ENABLED	true	Adds Server-Timing header to HTTP responses. More

Features

Trace linkage between the APM and RUM products

NewHandler wraps the passed handler, functioning like middleware. It adds trace context in traceparent form as Server-Timing header to the HTTP response:

Access-Control-Expose-Headers: Server-Timing
Server-Timing: traceparent;desc="00-<serverTraceId>-<serverSpanId>-01"

This information can be later consumed by the splunk-otel-js-web library.

Documentation

Overview

Package splunkhttp provides functions that add additional Splunk specific instrumentation by wrapping existing handlers.

Example

package main

import (
	"fmt"
	"io"
	"net/http"
	"net/http/httptest"

	"go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp"
	"go.opentelemetry.io/otel/sdk/trace"

	"github.com/signalfx/splunk-otel-go/instrumentation/net/http/splunkhttp"
)

func main() {
	var handler http.Handler = http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
		io.WriteString(w, "Hello world")
	})
	handler = splunkhttp.NewHandler(handler)
	handler = otelhttp.NewHandler(handler, "server", otelhttp.WithTracerProvider(trace.NewTracerProvider()))

	ts := httptest.NewServer(handler)
	defer ts.Close()
	resp, err := ts.Client().Get(ts.URL)
	if err != nil {
		fmt.Println(err)
		return
	}
	defer resp.Body.Close()

	fmt.Println("Access-Control-Expose-Headers:", resp.Header.Get("Access-Control-Expose-Headers"))
	fmt.Println("Server-Timing:", resp.Header.Get("Server-Timing"))
}

Index

• func NewHandler(handler http.Handler) http.Handler

Examples

• Package

Functions

func NewHandler

func NewHandler(handler http.Handler) http.Handler

NewHandler wraps the passed handler in a span named after the operation and with any provided Options. This will also enable all the Splunk specific defaults for HTTP tracing.