Merge pull request #9 from gol4ng/fixup-request-id

fixup #7

middleware/request_id.go

@@ -15,10 +15,11 @@ func RequestId(config *request_id.Config) httpware.Middleware {
 		return http.HandlerFunc(func(writer http.ResponseWriter, req *http.Request) {
 			id := req.Header.Get(config.HeaderName)
 			if id == "" {
-				id = config.GenerateId(req)
+				id = config.IdGenerator(req)
 			}
-			// add the request id to the context request
+			// add the request id to the current context request
 			r := req.WithContext(context.WithValue(req.Context(), config.HeaderName, id))
+			// add it to the response headers
 			writer.Header().Set(config.HeaderName, id)
 			next.ServeHTTP(writer, r)
 		})

middleware/request_id_test.go

@@ -43,7 +43,7 @@ func TestRequestIdCustom(t *testing.T) {
 		handlerReq = r
 	})
 	config := request_id.NewConfig()
-	config.GenerateId = func(request *http.Request) string {
+	config.IdGenerator = func(request *http.Request) string {
 		return "my_fake_request_id"
 	}
 
@@ -66,12 +66,12 @@ func ExampleRequestId() {
 	// you can override default header name
 	config.HeaderName = "my-personal-header-name"
 	// you can override default id generator
-	config.GenerateId = func(request *http.Request) string {
+	config.IdGenerator = func(request *http.Request) string {
 		return "my-fixed-request-id"
 	}
 
-	// we recommend to use MiddlewareStack to simplify managing all wanted middleware
-	// caution middleware order matter
+	// we recommend to use MiddlewareStack to simplify managing all wanted middlewares
+	// caution middleware order matters
 	stack := httpware.MiddlewareStack(
 		middleware.RequestId(config),
 	)
@@ -84,7 +84,7 @@ func ExampleRequestId() {
 	}()
 
 	resp, err := http.Get("http://localhost" + port)
-	fmt.Printf("%v %v\n", resp.Header.Get(config.HeaderName), err)
+	fmt.Printf("%s: %v %v\n", config.HeaderName, resp.Header.Get(config.HeaderName), err)
 
-	//Output: my-fixed-request-id <nil>
+	//Output: my-personal-header-name: my-fixed-request-id <nil>
 }

request_id/config.go

@@ -7,15 +7,13 @@ import (
 const HeaderName = "Request-Id"
 
 type Config struct {
-	HeaderName string
-	GenerateId func(*http.Request) string
+	HeaderName  string
+	IdGenerator func(*http.Request) string
 }
 
 func NewConfig() *Config {
 	return &Config{
-		HeaderName: HeaderName,
-		GenerateId: func(request *http.Request) string {
-			return RandomString(10) // eg: XPF0G5kqEG
-		},
+		HeaderName:  HeaderName,
+		IdGenerator: RandomIdGenerator,
 	}
 }

request_id/generator.go

@@ -2,9 +2,14 @@ package request_id
 
 import (
 	"math/rand"
+	"net/http"
 	"unsafe"
 )
 
+func RandomIdGenerator(_ *http.Request) string {
+	return randomString(10) // eg: XPF0G5kqEG
+}
+
 //https://stackoverflow.com/a/31832326
 const letterBytes = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"
 const (
@@ -13,7 +18,7 @@ const (
 	letterIdxMax  = 63 / letterIdxBits   // # of letter indices fitting in 63 bits
 )
 
-func RandomString(n int) string {
+func randomString(n int) string {
 	b := make([]byte, n)
 	// A src.Int63() generates 63 random bits, enough for letterIdxMax characters!
 	for i, cache, remain := n-1, rand.Int63(), letterIdxMax; i >= 0; {
@@ -27,7 +32,5 @@ func RandomString(n int) string {
 		cache >>= letterIdxBits
 		remain--
 	}
-
 	return *(*string)(unsafe.Pointer(&b))
 }
-

tripperware/request_id.go

@@ -8,8 +8,8 @@ import (
 	"github.com/gol4ng/httpware/request_id"
 )
 
-// RequestId middleware get request id header if provided or generate a request id
-// It will add the request ID to request context and add it to response header to
+// RequestId tripperware gets request id header if provided or generates a request id
+// It will add the request ID to request context
 func RequestId(config *request_id.Config) httpware.Tripperware {
 	return func(next http.RoundTripper) http.RoundTripper {
 		return httpware.RoundTripFunc(func(req *http.Request) (resp *http.Response, err error) {
@@ -18,7 +18,7 @@ func RequestId(config *request_id.Config) httpware.Tripperware {
 				id = req.Header.Get(config.HeaderName)
 			}
 			if id == "" {
-				id = config.GenerateId(req)
+				id = config.IdGenerator(req)
 			}
 			r := req.WithContext(context.WithValue(req.Context(), config.HeaderName, id))
 			r.Header.Add(config.HeaderName, id)

tripperware/request_id_test.go

@@ -2,14 +2,14 @@ package tripperware_test
 
 import (
 	"fmt"
-	"github.com/gol4ng/httpware"
 	"net/http"
 	"net/http/httptest"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/mock"
 
+	"github.com/gol4ng/httpware"
 	"github.com/gol4ng/httpware/mocks"
 	"github.com/gol4ng/httpware/request_id"
 	"github.com/gol4ng/httpware/tripperware"
@@ -49,7 +49,7 @@ func TestRequestIdCustom(t *testing.T) {
 	})
 
 	config := request_id.NewConfig()
-	config.GenerateId = func(request *http.Request) string {
+	config.IdGenerator = func(request *http.Request) string {
 		return "my_fake_request_id"
 	}
 
@@ -68,7 +68,7 @@ func ExampleRequestId() {
 	// you can override default header name
 	config.HeaderName = "my-personal-header-name"
 	// you can override default id generator
-	config.GenerateId = func(request *http.Request) string {
+	config.IdGenerator = func(request *http.Request) string {
 		return "my-generated-id"
 	}