Add robust test case & run it against Redis in CI

.github/workflows/ci.yml

@@ -0,0 +1,37 @@
+name: CI
+
+on:
+  push:
+  pull_request:
+
+jobs:
+  tests:
+    name: Tests
+    runs-on: ubuntu-latest
+
+    services:
+      redis:
+        image: redis:6
+        ports:
+          - 6379:6379
+
+    steps:
+      - name: Set up Go
+        uses: actions/setup-go@v5
+        with:
+          go-version: ^1.17
+
+      - name: Check out code into the Go module directory
+        uses: actions/checkout@v4
+
+      - name: Get dependencies
+        run: go get -v -t -d ./...
+
+      - name: Build
+        run: go build -v ./
+
+      - name: Build example
+        run: cd ./_example && go build -v ./
+
+      - name: Test
+        run: go test -v ./...

_example/go.mod

@@ -0,0 +1,14 @@
+module github.com/go-chi/httprate-redis/_example
+
+go 1.22.5
+
+replace github.com/go-chi/httprate-redis => ../
+
+require (
+	github.com/cespare/xxhash/v2 v2.3.0 // indirect
+	github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f // indirect
+	github.com/go-chi/chi/v5 v5.1.0 // indirect
+	github.com/go-chi/httprate v0.11.0 // indirect
+	github.com/go-chi/httprate-redis v0.3.0 // indirect
+	github.com/redis/go-redis/v9 v9.6.1 // indirect
+)

_example/go.sum

@@ -0,0 +1,12 @@
+github.com/cespare/xxhash/v2 v2.3.0 h1:UL815xU9SqsFlibzuggzjXhog7bL6oX9BbNZnL2UFvs=
+github.com/cespare/xxhash/v2 v2.3.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
+github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f h1:lO4WD4F/rVNCu3HqELle0jiPLLBs70cWOduZpkS1E78=
+github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f/go.mod h1:cuUVRXasLTGF7a8hSLbxyZXjz+1KgoB3wDUb6vlszIc=
+github.com/go-chi/chi/v5 v5.1.0 h1:acVI1TYaD+hhedDJ3r54HyA6sExp3HfXq7QWEEY/xMw=
+github.com/go-chi/chi/v5 v5.1.0/go.mod h1:DslCQbL2OYiznFReuXYUmQ2hGd1aDpCnlMNITLSKoi8=
+github.com/go-chi/httprate v0.11.0 h1:GKsQF0qlVSU1Zg/D07tUUnNrYTTkrtpMihwO6myxtzc=
+github.com/go-chi/httprate v0.11.0/go.mod h1:TUepLXaz/pCjmCtf/obgOQJ2Sz6rC8fSf5cAt5cnTt0=
+github.com/redis/go-redis/v9 v9.6.0 h1:NLck+Rab3AOTHw21CGRpvQpgTrAU4sgdCswqGtlhGRA=
+github.com/redis/go-redis/v9 v9.6.0/go.mod h1:hdY0cQFCN4fnSYT6TkisLufl/4W5UIXyv0b/CLO2V2M=
+github.com/redis/go-redis/v9 v9.6.1 h1:HHDteefn6ZkTtY5fGUE8tj8uy85AHk6zP7CpzIAM0y4=
+github.com/redis/go-redis/v9 v9.6.1/go.mod h1:0C0c6ycQsdpVNQpxb1njEQIqkx5UcsM8FJCQLgE9+RA=

_example/main.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"log"
 	"net/http"
 	"time"
 
@@ -16,18 +17,23 @@ func main() {
 
 	r.Group(func(r chi.Router) {
 		r.Use(httprate.Limit(
-			10,
-			10*time.Second,
+			5,
+			time.Minute,
 			httprate.WithKeyByIP(),
 			httprateredis.WithRedisLimitCounter(&httprateredis.Config{
 				Host: "127.0.0.1", Port: 6379,
 			}),
 		))
 
 		r.Get("/", func(w http.ResponseWriter, r *http.Request) {
-			w.Write([]byte("."))
+			w.Write([]byte("5 req/min\n"))
 		})
 	})
 
+	log.Printf("Serving at localhost:3333")
+	log.Println()
+	log.Printf("Try running:")
+	log.Printf("curl -v http://localhost:3333")
+
 	http.ListenAndServe(":3333", r)
 }

go.mod

@@ -10,4 +10,5 @@ require (
 require (
 	github.com/cespare/xxhash/v2 v2.3.0 // indirect
 	github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f // indirect
+	golang.org/x/sync v0.7.0 // indirect
 )

go.sum

@@ -14,3 +14,5 @@ github.com/redis/go-redis/v9 v9.3.0 h1:RiVDjmig62jIWp7Kk4XVLs0hzV6pI3PyTnnL0cnn0
 github.com/redis/go-redis/v9 v9.3.0/go.mod h1:hdY0cQFCN4fnSYT6TkisLufl/4W5UIXyv0b/CLO2V2M=
 github.com/redis/go-redis/v9 v9.6.0 h1:NLck+Rab3AOTHw21CGRpvQpgTrAU4sgdCswqGtlhGRA=
 github.com/redis/go-redis/v9 v9.6.0/go.mod h1:hdY0cQFCN4fnSYT6TkisLufl/4W5UIXyv0b/CLO2V2M=
+golang.org/x/sync v0.7.0 h1:YsImfSBoP9QPYL0xyKJPq0gcaJdG3rInoqxTWbfQu9M=
+golang.org/x/sync v0.7.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=

httprateredis_test.go

@@ -0,0 +1,152 @@
+package httprateredis_test
+
+import (
+	"fmt"
+	"math/rand"
+	"testing"
+	"time"
+
+	httprateredis "github.com/go-chi/httprate-redis"
+	"golang.org/x/sync/errgroup"
+)
+
+func TestRedisCounter(t *testing.T) {
+	limitCounter, err := httprateredis.NewRedisLimitCounter(&httprateredis.Config{
+		Host:       "localhost",
+		Port:       6379,
+		MaxIdle:    500,
+		MaxActive:  500,
+		DBIndex:    0,
+		ClientName: "httprateredis_test",
+		PrefixKey:  fmt.Sprintf("httprate:test:%v", rand.Int31n(100000)), // Unique key for each test
+	})
+	if err != nil {
+		t.Fatalf("redis not available: %v", err)
+	}
+
+	limitCounter.Config(1000, time.Minute)
+
+	currentWindow := time.Now().UTC().Truncate(time.Minute)
+	previousWindow := currentWindow.Add(-time.Minute)
+
+	type test struct {
+		name        string        // In each test do the following:
+		advanceTime time.Duration // 1. advance time
+		incrBy      int           // 2. increase counter
+		prev        int           // 3. check previous window counter
+		curr        int           //    and current window counter
+	}
+
+	tests := []test{
+		{
+			name: "t=0m: init",
+			prev: 0,
+			curr: 0,
+		},
+		{
+			name:   "t=0m: increment 1",
+			incrBy: 1,
+			prev:   0,
+			curr:   1,
+		},
+		{
+			name:   "t=0m: increment by 99",
+			incrBy: 99,
+			prev:   0,
+			curr:   100,
+		},
+		{
+			name:        "t=1m: move clock by 1m",
+			advanceTime: time.Minute,
+			prev:        100,
+			curr:        0,
+		},
+		{
+			name:   "t=1m: increment by 20",
+			incrBy: 20,
+			prev:   100,
+			curr:   20,
+		},
+		{
+			name:   "t=1m: increment by 20",
+			incrBy: 20,
+			prev:   100,
+			curr:   40,
+		},
+		{
+			name:        "t=2m: move clock by 1m",
+			advanceTime: time.Minute,
+			prev:        40,
+			curr:        0,
+		},
+		{
+			name:   "t=2m: incr++",
+			incrBy: 1,
+			prev:   40,
+			curr:   1,
+		},
+		{
+			name:   "t=2m: incr+=9",
+			incrBy: 9,
+			prev:   40,
+			curr:   10,
+		},
+		{
+			name:   "t=2m: incr+=20",
+			incrBy: 20,
+			prev:   40,
+			curr:   30,
+		},
+		{
+			name:        "t=4m: move clock by 2m",
+			advanceTime: 2 * time.Minute,
+			prev:        0,
+			curr:        0,
+		},
+	}
+
+	concurrentRequests := 1000
+
+	for _, tt := range tests {
+		if tt.advanceTime > 0 {
+			currentWindow = currentWindow.Add(tt.advanceTime)
+			previousWindow = previousWindow.Add(tt.advanceTime)
+		}
+
+		if tt.incrBy > 0 {
+			var g errgroup.Group
+			for i := 0; i < concurrentRequests; i++ {
+				i := i
+				g.Go(func() error {
+					key := fmt.Sprintf("key:%v", i)
+					return limitCounter.IncrementBy(key, currentWindow, tt.incrBy)
+				})
+			}
+			if err := g.Wait(); err != nil {
+				t.Errorf("%s: %v", tt.name, err)
+			}
+		}
+
+		var g errgroup.Group
+		for i := 0; i < concurrentRequests; i++ {
+			i := i
+			g.Go(func() error {
+				key := fmt.Sprintf("key:%v", i)
+				curr, prev, err := limitCounter.Get(key, currentWindow, previousWindow)
+				if err != nil {
+					return fmt.Errorf("%q: %w", key, err)
+				}
+				if curr != tt.curr {
+					return fmt.Errorf("%q: unexpected curr = %v, expected %v", key, curr, tt.curr)
+				}
+				if prev != tt.prev {
+					return fmt.Errorf("%q: unexpected prev = %v, expected %v", key, prev, tt.prev)
+				}
+				return nil
+			})
+		}
+		if err := g.Wait(); err != nil {
+			t.Errorf("%s: %v", tt.name, err)
+		}
+	}
+}