opentofu/vendor/github.com/newrelic/go-agent/README.md

New Relic Go Agent

Description

The New Relic Go Agent allows you to monitor your Go applications with New Relic. It helps you track transactions, outbound requests, database calls, and other parts of your Go application's behavior and provides a running overview of garbage collection, goroutine activity, and memory use.

Requirements

Go 1.3+ is required, due to the use of http.Client's Timeout field.

Linux, OS X, and Windows (Vista, Server 2008 and later) are supported.

Getting Started

Here are the basic steps to instrumenting your application. For more information, see GUIDE.md.

Step 0: Installation

Installing the Go Agent is the same as installing any other Go library. The simplest way is to run:

go get github.com/newrelic/go-agent

Then import the github.com/newrelic/go-agent package in your application.

Step 1: Create a Config and an Application

In your main function or an init block:

config := newrelic.NewConfig("Your Application Name", "__YOUR_NEW_RELIC_LICENSE_KEY__")
app, err := newrelic.NewApplication(config)

more info, application.go, config.go

Step 2: Add Transactions

Transactions time requests and background tasks. Use WrapHandle and WrapHandleFunc to create transactions for requests handled by the http standard library package.

http.HandleFunc(newrelic.WrapHandleFunc(app, "/users", usersHandler))

Alternatively, create transactions directly using the application's StartTransaction method:

txn := app.StartTransaction("myTxn", optionalResponseWriter, optionalRequest)
defer txn.End()

more info, transaction.go

Step 3: Instrument Segments

Segments show you where time in your transactions is being spent. At the beginning of important functions, add:

defer newrelic.StartSegment(txn, "mySegmentName").End()

more info, segments.go

Runnable Example

examples/server/main.go is an example that will appear as "My Go Application" in your New Relic applications list. To run it:

env NEW_RELIC_LICENSE_KEY=__YOUR_NEW_RELIC_LICENSE_KEY__LICENSE__ \
    go run examples/server/main.go

Some endpoints exposed are http://localhost:8000/ and http://localhost:8000/notice_error

Basic Example

Before Instrumentation

package main

import (
	"io"
	"net/http"
)

func helloHandler(w http.ResponseWriter, r *http.Request) {
	io.WriteString(w, "hello, world")
}

func main() {
	http.HandleFunc("/", helloHandler)
	http.ListenAndServe(":8000", nil)
}

After Instrumentation

package main

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

	"github.com/newrelic/go-agent"
)

func helloHandler(w http.ResponseWriter, r *http.Request) {
	io.WriteString(w, "hello, world")
}

func main() {
	// Create a config.  You need to provide the desired application name
	// and your New Relic license key.
	cfg := newrelic.NewConfig("My Go Application", "__YOUR_NEW_RELIC_LICENSE_KEY__")

	// Create an application.  This represents an application in the New
	// Relic UI.
	app, err := newrelic.NewApplication(cfg)
	if err != nil {
		fmt.Println(err)
		os.Exit(1)
	}

	// Wrap helloHandler.  The performance of this handler will be recorded.
	http.HandleFunc(newrelic.WrapHandleFunc(app, "/", helloHandler))
	http.ListenAndServe(":8000", nil)
}

Support

You can find more detailed documentation in the guide.

If you can't find what you're looking for there, reach out to us on our support site or our community forum and we'll be happy to help you.

Find a bug? Contact us via support.newrelic.com, or email support@newrelic.com.