upgrade (#14)

README.md

@@ -88,6 +88,7 @@ prevent a stampede scenario on your handler.
 to not include anything sensitive or user specific. In the case you require user-specific
 stampede handlers, make sure you pass a custom `keyFunc` to the `stampede.Handler` and
 split the cache by an account's id.
+
 See [example](_example/with_key.go) for a variety of examples.
 
 

_example/go.mod

@@ -0,0 +1,16 @@
+module example
+
+go 1.21.7
+
+replace github.com/go-chi/stampede => ../
+
+require (
+	github.com/go-chi/chi/v5 v5.0.11
+	github.com/go-chi/stampede v0.5.1
+)
+
+require (
+	github.com/cespare/xxhash/v2 v2.2.0 // indirect
+	github.com/goware/singleflight v0.2.0 // indirect
+	github.com/hashicorp/golang-lru/v2 v2.0.7 // indirect
+)

_example/go.sum

@@ -0,0 +1,18 @@
+github.com/cespare/xxhash/v2 v2.2.0 h1:DC2CZ1Ep5Y4k3ZQ899DldepgrayRUGE6BBZ/cd9Cj44=
+github.com/cespare/xxhash/v2 v2.2.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
+github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/go-chi/chi/v5 v5.0.11 h1:BnpYbFZ3T3S1WMpD79r7R5ThWX40TaFB7L31Y8xqSwA=
+github.com/go-chi/chi/v5 v5.0.11/go.mod h1:DslCQbL2OYiznFReuXYUmQ2hGd1aDpCnlMNITLSKoi8=
+github.com/go-chi/cors v1.2.0 h1:tV1g1XENQ8ku4Bq3K9ub2AtgG+p16SmzeMSGTwrOKdE=
+github.com/go-chi/cors v1.2.0/go.mod h1:sSbTewc+6wYHBBCW7ytsFSn836hqM7JxpglAy2Vzc58=
+github.com/goware/singleflight v0.2.0 h1:e/hZsvNmbLoiZLx3XbihH01oXYA2MwLFo4e+N017U4c=
+github.com/goware/singleflight v0.2.0/go.mod h1:SsAslCMS7HizXdbYcBQRBLC7HcNmFrHutRt3Hz6wovY=
+github.com/hashicorp/golang-lru/v2 v2.0.7 h1:a+bsQ5rvGLjzHuww6tVxozPZFVghXaHOwFs4luLUK2k=
+github.com/hashicorp/golang-lru/v2 v2.0.7/go.mod h1:QeFd9opnmA6QUJc5vARoKUSoFhyfM2/ZepoAG6RGpeM=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/testify v1.5.1 h1:nOGnQDM7FYENwehXlg/kFVnos3rEvtKTjRvOWSzb6H4=
+github.com/stretchr/testify v1.5.1/go.mod h1:5W2xD1RspED5o8YsWQXVCued0rvSQ+mT+I5cxcmMvtA=
+gopkg.in/yaml.v2 v2.2.2 h1:ZCJp+EgiOT7lHqUV2J862kp8Qj64Jo6az82+3Td9dZw=
+gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=

go.mod

@@ -1,10 +1,17 @@
 module github.com/go-chi/stampede
 
-go 1.16
+go 1.20
 
 require (
-	github.com/cespare/xxhash/v2 v2.1.2
+	github.com/cespare/xxhash/v2 v2.2.0
 	github.com/go-chi/cors v1.2.0
-	github.com/hashicorp/golang-lru v0.5.5-0.20200511160909-eb529947af53
+	github.com/goware/singleflight v0.2.0
+	github.com/hashicorp/golang-lru/v2 v2.0.7
 	github.com/stretchr/testify v1.5.1
 )
+
+require (
+	github.com/davecgh/go-spew v1.1.0 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	gopkg.in/yaml.v2 v2.2.2 // indirect
+)

go.sum

@@ -1,11 +1,13 @@
-github.com/cespare/xxhash/v2 v2.1.2 h1:YRXhKfTDauu4ajMg1TPgFO5jnlC2HCbmLXMcTG5cbYE=
-github.com/cespare/xxhash/v2 v2.1.2/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
+github.com/cespare/xxhash/v2 v2.2.0 h1:DC2CZ1Ep5Y4k3ZQ899DldepgrayRUGE6BBZ/cd9Cj44=
+github.com/cespare/xxhash/v2 v2.2.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
 github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/go-chi/cors v1.2.0 h1:tV1g1XENQ8ku4Bq3K9ub2AtgG+p16SmzeMSGTwrOKdE=
 github.com/go-chi/cors v1.2.0/go.mod h1:sSbTewc+6wYHBBCW7ytsFSn836hqM7JxpglAy2Vzc58=
-github.com/hashicorp/golang-lru v0.5.5-0.20200511160909-eb529947af53 h1:mcyf48FjrlX8JRXvy5v3LPeXBv+Um6WvoKS+kknfgIk=
-github.com/hashicorp/golang-lru v0.5.5-0.20200511160909-eb529947af53/go.mod h1:iADmTwqILo4mZ8BN3D2Q6+9jd8WM5uGBxy+E8yxSoD4=
+github.com/goware/singleflight v0.2.0 h1:e/hZsvNmbLoiZLx3XbihH01oXYA2MwLFo4e+N017U4c=
+github.com/goware/singleflight v0.2.0/go.mod h1:SsAslCMS7HizXdbYcBQRBLC7HcNmFrHutRt3Hz6wovY=
+github.com/hashicorp/golang-lru/v2 v2.0.7 h1:a+bsQ5rvGLjzHuww6tVxozPZFVghXaHOwFs4luLUK2k=
+github.com/hashicorp/golang-lru/v2 v2.0.7/go.mod h1:QeFd9opnmA6QUJc5vARoKUSoFhyfM2/ZepoAG6RGpeM=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=

http.go

@@ -2,10 +2,8 @@ package stampede
 
 import (
 	"bytes"
-	"context"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"strings"
 	"time"
@@ -27,8 +25,8 @@ func Handler(cacheSize int, ttl time.Duration, paths ...string) func(next http.H
 		// Read the request payload, and then setup buffer for future reader
 		var buf []byte
 		if r.Body != nil {
-			buf, _ = ioutil.ReadAll(r.Body)
-			r.Body = ioutil.NopCloser(bytes.NewBuffer(buf))
+			buf, _ = io.ReadAll(r.Body)
+			r.Body = io.NopCloser(bytes.NewBuffer(buf))
 		}
 
 		// Prepare cache key based on request URL path and the request data payload.
@@ -77,7 +75,7 @@ func HandlerWithKey(cacheSize int, ttl time.Duration, keyFunc func(r *http.Reque
 }
 
 func stampede(cacheSize int, ttl time.Duration, keyFunc func(r *http.Request) uint64) func(next http.Handler) http.Handler {
-	cache := NewCache(cacheSize, ttl, ttl*2)
+	cache := NewCacheKV[uint64, responseValue](cacheSize, ttl, ttl*2)
 
 	return func(next http.Handler) http.Handler {
 		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
@@ -89,7 +87,7 @@ func stampede(cacheSize int, ttl time.Duration, keyFunc func(r *http.Request) ui
 			first := false
 
 			// process request (single flight)
-			val, err := cache.GetFresh(r.Context(), key, func(ctx context.Context) (interface{}, error) {
+			respVal, err := cache.GetFresh(r.Context(), key, func() (responseValue, error) {
 				first = true
 				buf := bytes.NewBuffer(nil)
 				ww := &responseWriter{ResponseWriter: w, tee: buf}
@@ -116,22 +114,18 @@ func stampede(cacheSize int, ttl time.Duration, keyFunc func(r *http.Request) ui
 
 			// handle response for other listeners
 			if err != nil {
+				// TODO: perhaps just log error and execute standard handler..?
 				panic(fmt.Sprintf("stampede: fail to get value, %v", err))
 			}
 
-			resp, ok := val.(responseValue)
-			if !ok {
-				panic("stampede: handler received unexpected response value type")
-			}
-
-			if resp.skip {
+			if respVal.skip {
 				return
 			}
 
 			header := w.Header()
 
 		nextHeader:
-			for k := range resp.headers {
+			for k := range respVal.headers {
 				for _, match := range stripOutHeaders {
 					// Prevent any header in stripOutHeaders to override the current
 					// value of that header. This is important when you don't want a
@@ -142,11 +136,11 @@ func stampede(cacheSize int, ttl time.Duration, keyFunc func(r *http.Request) ui
 						continue nextHeader
 					}
 				}
-				header[k] = resp.headers[k]
+				header[k] = respVal.headers[k]
 			}
 
-			w.WriteHeader(resp.status)
-			w.Write(resp.body)
+			w.WriteHeader(respVal.status)
+			w.Write(respVal.body)
 		})
 	}
 }