Home

Awesome

GO Actuator

GoDoc Release Report Coverage Status Mentioned in Awesome Go

GO actuator configures the set of actuator endpoints for your application. It is very extensible and can be configured with Go's native HTTP Server Mux, or with any 3rd party web framework as well.

Project Versioning

Go actuator uses semantic versioning. API should not change between patch and minor releases. New minor versions may add additional features to the API.

Installation

To install Go Actuator package, you need to install Go and set your Go workspace first.

  1. The first need Go installed (version 1.13+ is required), then you can use the below Go command to install Go Actuator.
go get github.com/sinhashubham95/go-actuator
  1. Import it in your code:
import "github.com/sinhashubham95/go-actuator"

How to Use

The actuator library exposes a plain native handler function, and it is the responsibility of the application to put this handler to use. This can be used either directly with Go's native HTTP Server Mux, or with any 3rd party web framework as well.

Configuration

The configuration contains the following:-

  1. Endpoints - This is the list of endpoints which will be enabled. This is not a mandatory parameter. If not provided, then all the endpoints will be enabled. The possible endpoints are - /env, /info, /metrics, /ping, /shutdown and /threadDump. You can find the description of each of these endpoints below.
  2. Env - This is the environment where the application is running. For example, dev, stg, prod, etc.
  3. Name - This is the name of the application which is using this actuator library.
  4. Port - This is the port where the application is running.
  5. Version - This is the current application version.
import actuator "github.com/sinhashubham95/go-actuator"

config := &actuator.Config{
	Endpoints: []int{
		actuator.Env,
		actuator.Info,
		actuator.Metrics,
		actuator.Ping,
		actuator.Shutdown,
		actuator.ThreadDump,
    },
    Env: "dev",
    Name: "Naruto Rocks",
    Port: 8080,
    Version: "0.1.0",
}

Using with Go's Native Server Mux

import (
    actuator "github.com/sinhashubham95/go-actuator"
    "net/http"
)

// create a server
mux := &http.ServeMux{}

// get the handler for actuator
actuatorHandler := actuator.GetActuatorHandler(&Config{})
// configure the handler at this base endpoint
mux.Handle("/actuator", actuatorHandler)

// configure other handlers
....

Using with Fast HTTP

import (
	"strings"
	
    "github.com/valyala/fasthttp"
    actuator "github.com/sinhashubham95/go-actuator"
)

// get the handler for actuator
actuatorHandler := fasthttp.NewFastHTTPHandlerFunc(actuator.GetActuatorHandler(&Config{}))

// create a fast http handler
handler := func(ctx *fasthttp.RequestCtx) {
    if strings.HasPrefix(ctx.Path(), "/actuator") {
        // use the actuator handler
    	actuatorHandler(ctx)
    	return
    }
    // other request handler calls
}
fasthttp.ListenAndServe(":8080", handler)

Using with GIN

import (
    "github.com/gin-gonic/gin"
    actuator "github.com/sinhashubham95/go-actuator"
	"github.com/sinhashubham95/go-actuator/models"
)

// create the gin engine
engine := gin.Default()

// get the handler for actuator
actuatorHandler := actuator.GetActuatorHandler(&Config{})
ginActuatorHandler := func(ctx *gin.Context) {
	actuatorHandler(ctx.Writer, ctx.Request)
}

engine.GET("/actuator/*endpoint", ginActuatorHandler)

Endpoints

Env - /actuator/env

This is used to get all the environment variables for the runtime where the application is running. Note that to use this, you need to pass the runtime environment as an application flag as follows.

go build
./${APPLICATION_NAME}

{
  "env_key_1": "env_value_1",
  "env_key_2": "env_value_2"
}

Info - /actuator/info

This is used to get the basic information for an application. To get the correct and relevant information for your application you need to change the build script as well as the run script for your application as follows.

buildStamp=$(date -u '+%Y-%m-%d_%I:%M:%S%p')
commitId=$(git rev-list -1 HEAD)
commitTime=$(git show -s --format=%ci "$commitId")
commitAuthor=$(git --no-pager show -s --format='%an <%ae>' "$commitId")
gitUrl=$(git config --get remote.origin.url)
userName=$(whoami)
hostName=$(hostname)
go build -ldflags "<other linking params> -X github.com/sinhashubham95/go-actuator.BuildStamp=$buildStamp -X github.com/sinhashubham95/go-actuator.GitCommitID=$commitId -X github.com/sinhashubham95/go-actuator.GitPrimaryBranch=$2 -X github.com/sinhashubham95/go-actuator.GitURL=$gitUrl -X github.com/sinhashubham95/go-actuator.Username=$userName -X github.com/sinhashubham95/go-actuator.HostName=$hostName  -X \"github.com/sinhashubham95/go-actuator.GitCommitTime=$commitTime\" -X \"github.com/sinhashubham95/go-actuator.GitCommitAuthor=$commitAuthor\""
./${APPLICATION_NAME}

{
  "application": {
    "env": "ENVIRONMENT",
    "name": "APPLICATION_NAME",
    "version": "APPLICATION_VERSION"
  },
  "git": {
    "username": "s0s01qp",
    "hostName": "m-C02WV1L6HTD5",
    "buildStamp": "2019-08-22_09:44:04PM",
    "commitAuthor": "Shubham Sinha ",
    "commitId": "836475215e3ecf0ef26e0d5b65a9db626568ef89",
    "commitTime": "2019-08-23 02:27:26 +0530",
    "branch": "master",
    "url": "https://gecgithub01.walmart.com/RT-Integrated-Fulfillment/gif-ui-bff.git"
  },
  "runtime": {
    "arch": "",
    "os": "",
    "port": 8080,
    "runtimeVersion": ""
  }
}

Metrics - /actuator/metrics

This is used to get the runtime memory statistics for your application. You can find the definition of each of the fields here.

{
  "alloc": 2047816,
  "totalAlloc": 2850832,
  "sys": 73942024,
  "lookups": 0,
  "mAllocations": 15623,
  "frees": 9223,
  "heapAlloc": 2047816,
  "heapSys": 66551808,
  "heapIdle": 62832640,
  "heapInUse": 3719168,
  "heapReleased": 62570496,
  "heapObjects": 6400,
  "stackInUse": 557056,
  "stackSys": 557056,
  "mSpanInUse": 81056,
  "mSpanSys": 81920,
  "MCacheInUse": 19200,
  "mCacheSys": 32768,
  "buckHashSys": 1446250,
  "gcSys": 4225056,
  "otherSys": 1047166,
  "nextGC": 4194304,
  "lastGC": 1627102938524536000,
  "pauseTotalNs": 35655,
  "pauseNs": [
    35655
  ],
  "pauseEnd": [
    1627102938524536000
  ],
  "numGC": 1,
  "numForcedGC": 0,
  "gcCPUFraction": 0.000005360999257331059,
  "enableGC": true,
  "debugGC": false,
  "BySize": [
    {
      "Size": 0,
      "MAllocations": 0,
      "Frees": 0
    }
  ]
}

Ping - /actuator/ping

This is the lightweight ping endpoint that can be used along with your load balancer. This is used to know the running status of your application.

Shutdown - /actuator/shutdown

This is used to bring the application down.

Thread dump - /actuator/threadDump

This is used to get the trace of all the goroutines.

goroutine profile: total 1
1 @ 0x103af45 0x10337fb 0x10688f5 0x10c4de5 0x10c58b5 0x10c5897 0x1117e0f 0x1124391 0x11355e8 0x113576f 0x12037a5 0x1203676 0x1217025 0x1217007 0x121db9a 0x121e5b5 0x106e3e1
#	0x10688f4	internal/poll.runtime_pollWait+0x54				/Users/s0s01qp/go/go1.16.6/src/runtime/netpoll.go:222
#	0x10c4de4	internal/poll.(*pollDesc).wait+0x44				/Users/s0s01qp/go/go1.16.6/src/internal/poll/fd_poll_runtime.go:87
#	0x10c58b4	internal/poll.(*pollDesc).waitRead+0x1d4			/Users/s0s01qp/go/go1.16.6/src/internal/poll/fd_poll_runtime.go:92
#	0x10c5896	internal/poll.(*FD).Read+0x1b6					/Users/s0s01qp/go/go1.16.6/src/internal/poll/fd_unix.go:166
#	0x1117e0e	net.(*netFD).Read+0x4e						/Users/s0s01qp/go/go1.16.6/src/net/fd_posix.go:55
#	0x1124390	net.(*conn).Read+0x90						/Users/s0s01qp/go/go1.16.6/src/net/net.go:183
#	0x11355e7	bufio.(*Reader).fill+0x107					/Users/s0s01qp/go/go1.16.6/src/bufio/bufio.go:101
#	0x113576e	bufio.(*Reader).Peek+0x4e					/Users/s0s01qp/go/go1.16.6/src/bufio/bufio.go:139
#	0x12037a4	github.com/valyala/fasthttp.(*RequestHeader).tryRead+0x64	/Users/s0s01qp/go/pkg/mod/github.com/valyala/fasthttp@v1.28.0/header.go:1520
#	0x1203675	github.com/valyala/fasthttp.(*RequestHeader).readLoop+0x55	/Users/s0s01qp/go/pkg/mod/github.com/valyala/fasthttp@v1.28.0/header.go:1506
#	0x1217024	github.com/valyala/fasthttp.(*RequestHeader).Read+0x1ae4	/Users/s0s01qp/go/pkg/mod/github.com/valyala/fasthttp@v1.28.0/header.go:1497
#	0x1217006	github.com/valyala/fasthttp.(*Server).serveConn+0x1ac6		/Users/s0s01qp/go/pkg/mod/github.com/valyala/fasthttp@v1.28.0/server.go:2112
#	0x121db99	github.com/valyala/fasthttp.(*workerPool).workerFunc+0xb9	/Users/s0s01qp/go/pkg/mod/github.com/valyala/fasthttp@v1.28.0/workerpool.go:223
#	0x121e5b4	github.com/valyala/fasthttp.(*workerPool).getCh.func1+0x34	/Users/s0s01qp/go/pkg/mod/github.com/valyala/fasthttp@v1.28.0/workerpool.go:195