From e38c36ee0d6d2131b263b571a8a7e2e8e2a708dc Mon Sep 17 00:00:00 2001
From: Thomas Boerger <thomas@webhippie.de>
Date: Fri, 30 Jun 2017 21:22:40 +0200
Subject: [PATCH] Made funMaps for the templates configurable and
 hot-reloadable

---
 gin.go         | 18 ++++++++++++------
 render/html.go | 14 +++++++++-----
 2 files changed, 21 insertions(+), 11 deletions(-)

diff --git a/gin.go b/gin.go
index 992d2f15..c4118a4e 100644
--- a/gin.go
+++ b/gin.go
@@ -47,6 +47,7 @@ type (
 		RouterGroup
 		delims      render.Delims
 		HTMLRender  render.HTMLRender
+		FuncMap     template.FuncMap
 		allNoRoute  HandlersChain
 		allNoMethod HandlersChain
 		noRoute     HandlersChain
@@ -112,6 +113,7 @@ func New() *Engine {
 			basePath: "/",
 			root:     true,
 		},
+		FuncMap:                template.FuncMap{},
 		RedirectTrailingSlash:  true,
 		RedirectFixedPath:      false,
 		HandleMethodNotAllowed: false,
@@ -147,19 +149,19 @@ func (engine *Engine) Delims(left, right string) *Engine {
 
 func (engine *Engine) LoadHTMLGlob(pattern string) {
 	if IsDebugging() {
-		debugPrintLoadTemplate(template.Must(template.New("").Delims(engine.delims.Left, engine.delims.Right).ParseGlob(pattern)))
-		engine.HTMLRender = render.HTMLDebug{Glob: pattern, Delims: engine.delims}
+		debugPrintLoadTemplate(template.Must(template.New("").Delims(engine.delims.Left, engine.delims.Right).Funcs(engine.FuncMap).ParseGlob(pattern)))
+		engine.HTMLRender = render.HTMLDebug{Glob: pattern, FuncMap: engine.FuncMap, Delims: engine.delims}
 	} else {
-		templ := template.Must(template.New("").Delims(engine.delims.Left, engine.delims.Right).ParseGlob(pattern))
+		templ := template.Must(template.New("").Delims(engine.delims.Left, engine.delims.Right).Funcs(engine.FuncMap).ParseGlob(pattern))
 		engine.SetHTMLTemplate(templ)
 	}
 }
 
 func (engine *Engine) LoadHTMLFiles(files ...string) {
 	if IsDebugging() {
-		engine.HTMLRender = render.HTMLDebug{Files: files, Delims: engine.delims}
+		engine.HTMLRender = render.HTMLDebug{Files: files, FuncMap: engine.FuncMap, Delims: engine.delims}
 	} else {
-		templ := template.Must(template.New("").Delims(engine.delims.Left, engine.delims.Right).ParseFiles(files...))
+		templ := template.Must(template.New("").Delims(engine.delims.Left, engine.delims.Right).Funcs(engine.FuncMap).ParseFiles(files...))
 		engine.SetHTMLTemplate(templ)
 	}
 }
@@ -169,7 +171,11 @@ func (engine *Engine) SetHTMLTemplate(templ *template.Template) {
 		debugPrintWARNINGSetHTMLTemplate()
 	}
 
-	engine.HTMLRender = render.HTMLProduction{Template: templ}
+	engine.HTMLRender = render.HTMLProduction{Template: templ.Funcs(engine.FuncMap)}
+}
+
+func (engine *Engine) SetFuncMap(funcMap template.FuncMap) {
+	engine.FuncMap = funcMap
 }
 
 // NoRoute adds handlers for NoRoute. It return a 404 code by default.
diff --git a/render/html.go b/render/html.go
index 3ea5e08e..cf91219c 100644
--- a/render/html.go
+++ b/render/html.go
@@ -25,9 +25,10 @@ type (
 	}
 
 	HTMLDebug struct {
-		Files  []string
-		Glob   string
-		Delims Delims
+		Files   []string
+		Glob    string
+		Delims  Delims
+		FuncMap template.FuncMap
 	}
 
 	HTML struct {
@@ -55,11 +56,14 @@ func (r HTMLDebug) Instance(name string, data interface{}) Render {
 	}
 }
 func (r HTMLDebug) loadTemplate() *template.Template {
+	if r.FuncMap == nil {
+		r.FuncMap = template.FuncMap{}
+	}
 	if len(r.Files) > 0 {
-		return template.Must(template.New("").Delims(r.Delims.Left, r.Delims.Right).ParseFiles(r.Files...))
+		return template.Must(template.New("").Delims(r.Delims.Left, r.Delims.Right).Funcs(r.FuncMap).ParseFiles(r.Files...))
 	}
 	if len(r.Glob) > 0 {
-		return template.Must(template.New("").Delims(r.Delims.Left, r.Delims.Right).ParseGlob(r.Glob))
+		return template.Must(template.New("").Delims(r.Delims.Left, r.Delims.Right).Funcs(r.FuncMap).ParseGlob(r.Glob))
 	}
 	panic("the HTML debug render was created without files or glob pattern")
 }