add QueryParams() url.Values function for caching multiple access to URL.Query() Values

Author: Dean Karn

README.md

@@ -1,6 +1,6 @@
 ##LARS
 <img align="right" src="https://raw.githubusercontent.com/go-playground/lars/master/examples/README/test.gif">
-![Project status](https://img.shields.io/badge/version-3.3.1-green.svg)
+![Project status](https://img.shields.io/badge/version-3.4.0-green.svg)
 [![Build Status](https://semaphoreci.com/api/v1/projects/4351aa2d-2f94-40be-a6ef-85c248490378/679708/badge.svg)](https://semaphoreci.com/joeybloggs/lars)
 [![Coverage Status](https://coveralls.io/repos/github/go-playground/lars/badge.svg?branch=master)](https://coveralls.io/github/go-playground/lars?branch=master)
 [![Go Report Card](https://goreportcard.com/badge/go-playground/lars)](https://goreportcard.com/report/go-playground/lars)

context.go

@@ -6,6 +6,7 @@ import (
 	"io"
 	"net"
 	"net/http"
+	"net/url"
 	"strings"
 
 	"github.com/gorilla/websocket"
@@ -74,6 +75,22 @@ func (c *Ctx) Param(name string) string {
 	return blank
 }
 
+// QueryParams returns the http.Request.URL.Query() values
+// this function is not for convenience, but rather performance
+// URL.Query() reparses the RawQuery every time it's called, but this
+// function will cache the initial parsing so it doesn't have to reparse;
+// which is useful if when accessing these Params from multiple middleware.
+func (c *Ctx) QueryParams() url.Values {
+
+	if c.queryParams != nil {
+		return c.queryParams
+	}
+
+	c.queryParams = c.request.URL.Query()
+
+	return c.queryParams
+}
+
 // ParseForm calls the underlying http.Request ParseForm
 // but also adds the URL params to the request Form as if
 // they were defined as query params i.e. ?id=13&ok=true but

context_16.go

@@ -5,6 +5,7 @@ package lars
 import (
 	"io"
 	"net/http"
+	"net/url"
 	"time"
 
 	"github.com/gorilla/websocket"
@@ -18,6 +19,7 @@ type Context interface {
 	Response() *Response
 	WebSocket() *websocket.Conn
 	Param(name string) string
+	QueryParams() url.Values
 	ParseForm() error
 	ParseMultipartForm(maxMemory int64) error
 	Set(key interface{}, value interface{})
@@ -57,6 +59,7 @@ type Ctx struct {
 	response            *Response
 	websocket           *websocket.Conn
 	params              Params
+	queryParams         url.Values
 	handlers            HandlersChain
 	parent              Context
 	handlerName         string
@@ -70,6 +73,7 @@ func (c *Ctx) RequestStart(w http.ResponseWriter, r *http.Request) {
 	c.request = r
 	c.response.reset(w)
 	c.params = c.params[0:0]
+	c.queryParams = nil
 	c.netContext = context.Background() // in go 1.7 will call r.Context(), netContext will go away and be replaced with the Request objects Context
 	c.index = -1
 	c.handlers = nil

context_17.go

@@ -6,6 +6,7 @@ import (
 	"context"
 	"io"
 	"net/http"
+	"net/url"
 	"time"
 
 	"github.com/gorilla/websocket"
@@ -18,6 +19,7 @@ type Context interface {
 	Response() *Response
 	WebSocket() *websocket.Conn
 	Param(name string) string
+	QueryParams() url.Values
 	ParseForm() error
 	ParseMultipartForm(maxMemory int64) error
 	Set(key interface{}, value interface{})
@@ -56,6 +58,7 @@ type Ctx struct {
 	response            *Response
 	websocket           *websocket.Conn
 	params              Params
+	queryParams         url.Values
 	handlers            HandlersChain
 	parent              Context
 	handlerName         string
@@ -69,6 +72,7 @@ func (c *Ctx) RequestStart(w http.ResponseWriter, r *http.Request) {
 	c.request = r
 	c.response.reset(w)
 	c.params = c.params[0:0]
+	c.queryParams = nil
 	c.index = -1
 	c.handlers = nil
 	c.formParsed = false

context_test.go

@@ -723,3 +723,28 @@ func TestText(t *testing.T) {
 	Equal(t, w.Header().Get(ContentType), TextPlainCharsetUTF8)
 	Equal(t, w.Body.String(), txtData)
 }
+
+func TestCachedQueryParams(t *testing.T) {
+
+	var val1, val2 string
+
+	l := New()
+	l.Use(func(c Context) {
+		val1 = c.QueryParams()["key1"][0]
+
+		c.Next()
+	})
+	l.Get("/test", func(c Context) {
+		val2 = c.QueryParams()["key2"][0]
+	})
+
+	hf := l.Serve()
+
+	r, _ := http.NewRequest(GET, "/test?key1=val1&key2=val2", nil)
+	w := httptest.NewRecorder()
+	hf.ServeHTTP(w, r)
+
+	Equal(t, w.Code, http.StatusOK)
+	Equal(t, val1, "val1")
+	Equal(t, val2, "val2")
+}

lars_test.go

@@ -77,7 +77,7 @@ func TestFindOneOffs(t *testing.T) {
 	PanicMatches(t, func() { l.Get("/zombies/:id/", basicHandler) }, "handlers are already registered for path '/zombies/:id/'")
 }
 
-func Testlars(t *testing.T) {
+func TestLARS(t *testing.T) {
 	l := New()
 
 	l.Get("/", func(c Context) {
@@ -91,7 +91,7 @@ func Testlars(t *testing.T) {
 	Equal(t, body, "home")
 }
 
-func TestlarsStatic(t *testing.T) {
+func TestLARSStatic(t *testing.T) {
 	l := New()
 	path := "/github.com/go-playground/:id"
 	l.Get(path, basicHandler)
@@ -100,7 +100,7 @@ func TestlarsStatic(t *testing.T) {
 	Equal(t, body, "")
 }
 
-func TestlarsParam(t *testing.T) {
+func TestLARSParam(t *testing.T) {
 	l := New()
 	path := "/github.com/go-playground/:id/"
 	l.Get(path, func(c Context) {
@@ -115,7 +115,7 @@ func TestlarsParam(t *testing.T) {
 	Equal(t, body, "808w70")
 }
 
-func TestlarsTwoParam(t *testing.T) {
+func TestLARSTwoParam(t *testing.T) {
 	var p1 string
 	var p2 string