✨ add rate limit sample

Author: yuanyu90221

.gitignore

@@ -0,0 +1,28 @@
+# If you prefer the allow list template instead of the deny list, see community template:
+# https://github.com/github/gitignore/blob/main/community/Golang/Go.AllowList.gitignore
+#
+# Binaries for programs and plugins
+*.exe
+*.exe~
+*.dll
+*.so
+*.dylib
+
+# Test binary, built with `go test -c`
+*.test
+
+# Output of the go coverage tool, specifically when used with LiteIDE
+*.out
+
+# Dependency directories (remove the comment below to include it)
+# vendor/
+
+# Go workspace file
+go.work
+go.work.sum
+
+# env file
+.env
+bin
+gg
+mage

README.md

@@ -0,0 +1,63 @@
+# golang-sample-with-rate-limiter
+
+This repository is to demo how to use golang standard library to implement rate limiter
+
+## logic
+
+1. install package
+```shell
+go get golang.org/x/time/rate
+```
+
+2. setup rate limiter
+```golang
+package rate_limiter
+
+import (
+	"encoding/json"
+	"log"
+	"net"
+	"net/http"
+
+	"golang.org/x/time/rate"
+)
+
+type RateLimiter struct{}
+
+// getIP - 取得 request IP
+func (r *RateLimiter) getIP(req *http.Request) string {
+	host, _, err := net.SplitHostPort(req.RemoteAddr)
+	if err != nil {
+		log.Printf("Error parsing IP: %v", err)
+		return ""
+	}
+	return host
+}
+
+// RateLimiterMiddleware - 建立 ratelimiter middleware
+func (r *RateLimiter) RateLimiterMiddleware(next http.Handler, limit rate.Limit, burst int) http.Handler {
+	ipLimiterMap := make(map[string]*rate.Limiter)
+	return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
+		// Fetch IP
+		ip := r.getIP(req)
+		// Create limiter if not present for IP
+		limiter, exists := ipLimiterMap[ip]
+		if !exists {
+			limiter = rate.NewLimiter(limit, burst)
+			ipLimiterMap[ip] = limiter
+		}
+		// return error if the limit has been reached
+		if !limiter.Allow() {
+			w.Header().Set("Content-Type", "application/json")
+			w.WriteHeader(http.StatusTooManyRequests)
+			json.NewEncoder(w).Encode(map[string]string{"error": "Too many requests"})
+			return
+		}
+		next.ServeHTTP(w, req)
+	})
+}
+
+func NewRateLimiter() *RateLimiter {
+	return &RateLimiter{}
+}
+```

Taskfile.yml

@@ -0,0 +1,42 @@
+version: '3'
+
+dotenv: ['.env']
+
+tasks:
+  default:
+    cmds:
+      - echo "PORT=$PORT"
+    silent: true
+  
+  # build:
+  #   cmds:
+  #     - CGO_ENABLED=0 GOOS=linux go build -o bin/main cmd/main.go
+  #   silent: true
+  # run:
+  #   cmds:
+  #     - ./bin/main
+  #   deps:
+  #     - build
+  #   silent: true
+
+  build-mage:
+    cmds:
+      - CGO_ENABLED=0 GOOS=linux go build -o ./mage mage-tools/mage.go
+    silent: true
+  
+  build-gg:
+    cmds:
+      - ./mage -d mage-tools -compile ../gg
+    deps:
+      - build-mage
+    silent: true
+
+  coverage:
+    cmds:
+      - go test -v -cover ./...
+    silent: true
+  test:
+    cmds:
+      - go test -v ./...
+    silent: true
+  

cmd/client/main.go

@@ -0,0 +1,23 @@
+package main
+
+import (
+	"fmt"
+	"net/http"
+	"time"
+
+	"github.com/leetcode-golang-classroom/golang-sample-with-rate-limiter/internal/config"
+)
+
+func main() {
+	url := fmt.Sprintf("http://localhost:%s", config.AppConfig.Port)
+
+	for i := 1; i <= 50; i++ {
+		resp, err := http.Get(url)
+		if err != nil {
+			fmt.Println("Error making request:", err)
+			continue
+		}
+		fmt.Printf("Request: %2d: Status: %d\n", i, resp.StatusCode)
+		time.Sleep(100 * time.Millisecond) // Adjust timing to test rate limiting
+	}
+}

cmd/server/main.go

@@ -0,0 +1,25 @@
+package main
+
+import (
+	"context"
+	"log"
+	"os"
+	"os/signal"
+	"syscall"
+
+	"github.com/leetcode-golang-classroom/golang-sample-with-rate-limiter/internal/application"
+	"github.com/leetcode-golang-classroom/golang-sample-with-rate-limiter/internal/config"
+)
+
+func main() {
+	// 建立 application instance
+	app := application.New(config.AppConfig)
+	// 設定中斷訊號監聽
+	ctx, cancel := signal.NotifyContext(context.Background(), os.Interrupt,
+		syscall.SIGTERM, syscall.SIGINT)
+	defer cancel()
+	err := app.Start(ctx)
+	if err != nil {
+		log.Println("failed to start app:", err)
+	}
+}

go.mod

@@ -0,0 +1,31 @@
+module github.com/leetcode-golang-classroom/golang-sample-with-rate-limiter
+
+go 1.22.4
+
+require (
+	github.com/magefile/mage v1.15.0
+	github.com/spf13/viper v1.19.0
+	golang.org/x/time v0.10.0
+)
+
+require (
+	github.com/fsnotify/fsnotify v1.7.0 // indirect
+	github.com/hashicorp/hcl v1.0.0 // indirect
+	github.com/magiconair/properties v1.8.7 // indirect
+	github.com/mitchellh/mapstructure v1.5.0 // indirect
+	github.com/pelletier/go-toml/v2 v2.2.2 // indirect
+	github.com/sagikazarmark/locafero v0.4.0 // indirect
+	github.com/sagikazarmark/slog-shim v0.1.0 // indirect
+	github.com/sourcegraph/conc v0.3.0 // indirect
+	github.com/spf13/afero v1.11.0 // indirect
+	github.com/spf13/cast v1.6.0 // indirect
+	github.com/spf13/pflag v1.0.5 // indirect
+	github.com/subosito/gotenv v1.6.0 // indirect
+	go.uber.org/atomic v1.9.0 // indirect
+	go.uber.org/multierr v1.9.0 // indirect
+	golang.org/x/exp v0.0.0-20230905200255-921286631fa9 // indirect
+	golang.org/x/sys v0.18.0 // indirect
+	golang.org/x/text v0.14.0 // indirect
+	gopkg.in/ini.v1 v1.67.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+)

go.sum

@@ -0,0 +1,75 @@
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc h1:U9qPSI2PIWSS1VwoXQT9A3Wy9MM3WgvqSxFWenqJduM=
+github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/frankban/quicktest v1.14.6 h1:7Xjx+VpznH+oBnejlPUj8oUpdxnVs4f8XU8WnHkI4W8=
+github.com/frankban/quicktest v1.14.6/go.mod h1:4ptaffx2x8+WTWXmUCuVU6aPUX1/Mz7zb5vbUoiM6w0=
+github.com/fsnotify/fsnotify v1.7.0 h1:8JEhPFa5W2WU7YfeZzPNqzMP6Lwt7L2715Ggo0nosvA=
+github.com/fsnotify/fsnotify v1.7.0/go.mod h1:40Bi/Hjc2AVfZrqy+aj+yEI+/bRxZnMJyTJwOpGvigM=
+github.com/google/go-cmp v0.5.9 h1:O2Tfq5qg4qc4AmwVlvv0oLiVAGB7enBSJ2x2DqQFi38=
+github.com/google/go-cmp v0.5.9/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
+github.com/hashicorp/hcl v1.0.0 h1:0Anlzjpi4vEasTeNFn2mLJgTSwt0+6sfsiTG8qcWGx4=
+github.com/hashicorp/hcl v1.0.0/go.mod h1:E5yfLk+7swimpb2L/Alb/PJmXilQ/rhwaUYs4T20WEQ=
+github.com/kr/pretty v0.3.1 h1:flRD4NNwYAUpkphVc1HcthR4KEIFJ65n8Mw5qdRn3LE=
+github.com/kr/pretty v0.3.1/go.mod h1:hoEshYVHaxMs3cyo3Yncou5ZscifuDolrwPKZanG3xk=
+github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
+github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
+github.com/magefile/mage v1.15.0 h1:BvGheCMAsG3bWUDbZ8AyXXpCNwU9u5CB6sM+HNb9HYg=
+github.com/magefile/mage v1.15.0/go.mod h1:z5UZb/iS3GoOSn0JgWuiw7dxlurVYTu+/jHXqQg881A=
+github.com/magiconair/properties v1.8.7 h1:IeQXZAiQcpL9mgcAe1Nu6cX9LLw6ExEHKjN0VQdvPDY=
+github.com/magiconair/properties v1.8.7/go.mod h1:Dhd985XPs7jluiymwWYZ0G4Z61jb3vdS329zhj2hYo0=
+github.com/mitchellh/mapstructure v1.5.0 h1:jeMsZIYE/09sWLaz43PL7Gy6RuMjD2eJVyuac5Z2hdY=
+github.com/mitchellh/mapstructure v1.5.0/go.mod h1:bFUtVrKA4DC2yAKiSyO/QUcy7e+RRV2QTWOzhPopBRo=
+github.com/pelletier/go-toml/v2 v2.2.2 h1:aYUidT7k73Pcl9nb2gScu7NSrKCSHIDE89b3+6Wq+LM=
+github.com/pelletier/go-toml/v2 v2.2.2/go.mod h1:1t835xjRzz80PqgE6HHgN2JOsmgYu/h4qDAS4n929Rs=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2 h1:Jamvg5psRIccs7FGNTlIRMkT8wgtp5eCXdBlqhYGL6U=
+github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/rogpeppe/go-internal v1.9.0 h1:73kH8U+JUqXU8lRuOHeVHaa/SZPifC7BkcraZVejAe8=
+github.com/rogpeppe/go-internal v1.9.0/go.mod h1:WtVeX8xhTBvf0smdhujwtBcq4Qrzq/fJaraNFVN+nFs=
+github.com/sagikazarmark/locafero v0.4.0 h1:HApY1R9zGo4DBgr7dqsTH/JJxLTTsOt7u6keLGt6kNQ=
+github.com/sagikazarmark/locafero v0.4.0/go.mod h1:Pe1W6UlPYUk/+wc/6KFhbORCfqzgYEpgQ3O5fPuL3H4=
+github.com/sagikazarmark/slog-shim v0.1.0 h1:diDBnUNK9N/354PgrxMywXnAwEr1QZcOr6gto+ugjYE=
+github.com/sagikazarmark/slog-shim v0.1.0/go.mod h1:SrcSrq8aKtyuqEI1uvTDTK1arOWRIczQRv+GVI1AkeQ=
+github.com/sourcegraph/conc v0.3.0 h1:OQTbbt6P72L20UqAkXXuLOj79LfEanQ+YQFNpLA9ySo=
+github.com/sourcegraph/conc v0.3.0/go.mod h1:Sdozi7LEKbFPqYX2/J+iBAM6HpqSLTASQIKqDmF7Mt0=
+github.com/spf13/afero v1.11.0 h1:WJQKhtpdm3v2IzqG8VMqrr6Rf3UYpEF239Jy9wNepM8=
+github.com/spf13/afero v1.11.0/go.mod h1:GH9Y3pIexgf1MTIWtNGyogA5MwRIDXGUr+hbWNoBjkY=
+github.com/spf13/cast v1.6.0 h1:GEiTHELF+vaR5dhz3VqZfFSzZjYbgeKDpBxQVS4GYJ0=
+github.com/spf13/cast v1.6.0/go.mod h1:ancEpBxwJDODSW/UG4rDrAqiKolqNNh2DX3mk86cAdo=
+github.com/spf13/pflag v1.0.5 h1:iy+VFUOCP1a+8yFto/drg2CJ5u0yRoB7fZw3DKv/JXA=
+github.com/spf13/pflag v1.0.5/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
+github.com/spf13/viper v1.19.0 h1:RWq5SEjt8o25SROyN3z2OrDB9l7RPd3lwTWU8EcEdcI=
+github.com/spf13/viper v1.19.0/go.mod h1:GQUN9bilAbhU/jgc1bKs99f/suXKeUMct8Adx5+Ntkg=
+github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSSt89Yw=
+github.com/stretchr/objx v0.5.0/go.mod h1:Yh+to48EsGEfYuaHDzXPcE3xhTkx73EhmCGUpEOglKo=
+github.com/stretchr/objx v0.5.2/go.mod h1:FRsXN1f5AsAjCGJKqEizvkpNtU+EGNCLh3NxZ/8L+MA=
+github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
+github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
+github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
+github.com/stretchr/testify v1.9.0 h1:HtqpIVDClZ4nwg75+f6Lvsy/wHu+3BoSGCbBAcpTsTg=
+github.com/stretchr/testify v1.9.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
+github.com/subosito/gotenv v1.6.0 h1:9NlTDc1FTs4qu0DDq7AEtTPNw6SVm7uBMsUCUjABIf8=
+github.com/subosito/gotenv v1.6.0/go.mod h1:Dk4QP5c2W3ibzajGcXpNraDfq2IrhjMIvMSWPKKo0FU=
+go.uber.org/atomic v1.9.0 h1:ECmE8Bn/WFTYwEW/bpKD3M8VtR/zQVbavAoalC1PYyE=
+go.uber.org/atomic v1.9.0/go.mod h1:fEN4uk6kAWBTFdckzkM89CLk9XfWZrxpCo0nPH17wJc=
+go.uber.org/multierr v1.9.0 h1:7fIwc/ZtS0q++VgcfqFDxSBZVv/Xo49/SYnDFupUwlI=
+go.uber.org/multierr v1.9.0/go.mod h1:X2jQV1h+kxSjClGpnseKVIxpmcjrj7MNnI0bnlfKTVQ=
+golang.org/x/exp v0.0.0-20230905200255-921286631fa9 h1:GoHiUyI/Tp2nVkLI2mCxVkOjsbSXD66ic0XW0js0R9g=
+golang.org/x/exp v0.0.0-20230905200255-921286631fa9/go.mod h1:S2oDrQGGwySpoQPVqRShND87VCbxmc6bL1Yd2oYrm6k=
+golang.org/x/sys v0.18.0 h1:DBdB3niSjOA/O0blCZBqDefyWNYveAYMNF1Wum0DYQ4=
+golang.org/x/sys v0.18.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+golang.org/x/text v0.14.0 h1:ScX5w1eTa3QqT8oi6+ziP7dTV1S2+ALU0bI+0zXKWiQ=
+golang.org/x/text v0.14.0/go.mod h1:18ZOQIKpY8NJVqYksKHtTdi31H5itFRjB5/qKTNYzSU=
+golang.org/x/time v0.10.0 h1:3usCWA8tQn0L8+hFJQNgzpWbd89begxN66o1Ojdn5L4=
+golang.org/x/time v0.10.0/go.mod h1:3BpzKBy/shNhVucY/MWOyx10tF3SFh9QdLuxbVysPQM=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15 h1:YR8cESwS4TdDjEe65xsg0ogRM/Nc3DYOhEAlW+xobZo=
+gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/ini.v1 v1.67.0 h1:Dgnx+6+nfE+IfzjUEISNeydPJh9AXNNsWbGP9KzCsOA=
+gopkg.in/ini.v1 v1.67.0/go.mod h1:pNLf8WUiyNEtQjuu5G5vTm06TEv9tsIgeAvK8hOrP4k=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

internal/application/app.go

@@ -0,0 +1,68 @@
+package application
+
+import (
+	"context"
+	"fmt"
+	"log"
+	"net/http"
+	"time"
+
+	"github.com/leetcode-golang-classroom/golang-sample-with-rate-limiter/internal/config"
+	rateLimiter "github.com/leetcode-golang-classroom/golang-sample-with-rate-limiter/internal/service/rate_limiter"
+	"golang.org/x/time/rate"
+)
+
+type App struct {
+	appConfig *config.Config
+	router    *http.ServeMux
+}
+
+// New - 建立 App 物件
+func New(appConfig *config.Config) *App {
+	router := http.NewServeMux()
+	// create app instance
+	app := &App{
+		appConfig: appConfig,
+		router:    router,
+	}
+	// setup route
+	app.setupGreetingRoute()
+	return app
+}
+
+// Start - 啟動 server
+func (app *App) Start(ctx context.Context) error {
+	// setup rateLimiter
+	rateLimitMux := rateLimiter.NewRateLimiter()
+	handler := rateLimitMux.RateLimiterMiddleware(app.router, rate.Limit(1), 10)
+	// setup server
+	server := &http.Server{
+		Addr:    fmt.Sprintf(":%s", app.appConfig.Port),
+		Handler: handler,
+	}
+	log.Printf("starting server on %s", app.appConfig.Port)
+	errCh := make(chan error, 1)
+	var err error
+	go func() {
+		err = server.ListenAndServe()
+		if err != nil {
+			errCh <- fmt.Errorf("failed to start server: %w", err)
+		}
+		CloseChannel(errCh)
+	}()
+	select {
+	case err = <-errCh:
+		return err
+	case <-ctx.Done():
+		timeout, cancel := context.WithTimeout(context.Background(), time.Second*10)
+		log.Printf("stopping server, wait for 10 seconds to stop")
+		defer cancel()
+		return server.Shutdown(timeout)
+	}
+}
+
+func CloseChannel(ch chan error) {
+	if _, ok := <-ch; ok {
+		close(ch)
+	}
+}

internal/application/route.go

@@ -0,0 +1,8 @@
+package application
+
+import "github.com/leetcode-golang-classroom/golang-sample-with-rate-limiter/internal/service/greeting"
+
+func (app *App) setupGreetingRoute() {
+	greetingRoute := greeting.NewRoute()
+	greetingRoute.SetupRoute(app.router)
+}