Add View Engine Benchmarks: https://github.com/kataras/iris/tree/master/_benchmarks/view

view/README.md

@@ -19,6 +19,8 @@ Parse using embedded assets, Layouts and Party-specific layout, Template Funcs,
 
 [List of Examples](https://github.com/kataras/iris/tree/master/_examples/view).
 
+[Benchmarks](https://github.com/kataras/iris/tree/master/_benchmarks/view).
+
 You can serve [quicktemplate](https://github.com/valyala/quicktemplate) files too, simply by using the `Context.ResponseWriter`, take a look at the [iris/_examples/view/quicktemplate](https://github.com/kataras/iris/tree/master/_examples/view/quicktemplate) example.
 
 ## Overview

view/ace.go

@@ -6,10 +6,28 @@ import (
 	"github.com/yosssi/ace"
 )
 
-// Ace returns a new ace view engine.
+// AceEngine represents the Ace view engine.
+// See the `Ace` package-level function for more.
+type AceEngine struct {
+	*HTMLEngine
+
+	indent string
+}
+
+// SetIndent string used for indentation.
+// Do NOT use tabs, only spaces characters.
+// Defaults to minified response, no indentation.
+func (s *AceEngine) SetIndent(indent string) *AceEngine {
+	s.indent = indent
+	return s
+}
+
+// Ace returns a new Ace view engine.
 // It shares the same exactly logic with the
 // html view engine, it uses the same exactly configuration.
 // The given "extension" MUST begin with a dot.
+// Ace minifies the response automatically unless
+// SetIndent() method is set.
 //
 // Read more about the Ace Go Parser: https://github.com/yosssi/ace
 //
@@ -17,13 +35,14 @@ import (
 // Ace("./views", ".ace") or
 // Ace(iris.Dir("./views"), ".ace") or
 // Ace(AssetFile(), ".ace") for embedded data.
-func Ace(fs interface{}, extension string) *HTMLEngine {
-	s := HTML(fs, extension)
+func Ace(fs interface{}, extension string) *AceEngine {
+	s := &AceEngine{HTMLEngine: HTML(fs, extension), indent: ""}
 	s.name = "Ace"
 
 	funcs := make(map[string]interface{}, 0)
 
 	once := new(sync.Once)
+
 	s.middleware = func(name string, text []byte) (contents string, err error) {
 		once.Do(func() { // on first template parse, all funcs are given.
 			for k, v := range emptyFuncs {
@@ -43,17 +62,20 @@ func Ace(fs interface{}, extension string) *HTMLEngine {
 			[]*ace.File{},
 		)
 
-		rslt, err := ace.ParseSource(src, nil)
-		if err != nil {
-			return "", err
-		}
-
-		t, err := ace.CompileResult(name, rslt, &ace.Options{
+		opts := &ace.Options{
 			Extension:  extension[1:],
 			FuncMap:    funcs,
 			DelimLeft:  s.left,
 			DelimRight: s.right,
-		})
+			Indent:     s.indent,
+		}
+
+		rslt, err := ace.ParseSource(src, opts)
+		if err != nil {
+			return "", err
+		}
+
+		t, err := ace.CompileResult(name, rslt, opts)
 		if err != nil {
 			return "", err
 		}

view/amber.go

@@ -1,6 +1,7 @@
 package view
 
 import (
+	"bytes"
 	"fmt"
 	"html/template"
 	"io"
@@ -9,6 +10,7 @@ import (
 	"path/filepath"
 	"strings"
 	"sync"
+	"sync/atomic"
 
 	"github.com/eknkc/amber"
 )
@@ -23,6 +25,7 @@ type AmberEngine struct {
 	//
 	rmu           sync.RWMutex // locks for `ExecuteWiter` when `reload` is true.
 	templateCache map[string]*template.Template
+	bufPool       *sync.Pool
 
 	Options amber.Options
 }
@@ -32,6 +35,8 @@ var (
 	_ EngineFuncer = (*AmberEngine)(nil)
 )
 
+var amberOnce = new(uint32)
+
 // Amber creates and returns a new amber view engine.
 // The given "extension" MUST begin with a dot.
 //
@@ -40,6 +45,12 @@ var (
 // Amber(iris.Dir("./views"), ".amber") or
 // Amber(AssetFile(), ".amber") for embedded data.
 func Amber(fs interface{}, extension string) *AmberEngine {
+	if atomic.LoadUint32(amberOnce) > 0 {
+		panic("Amber: cannot be registered twice as its internal implementation share the same template functions across instances.")
+	} else {
+		atomic.StoreUint32(amberOnce, 1)
+	}
+
 	fileSystem := getFS(fs)
 	s := &AmberEngine{
 		fs:            fileSystem,
@@ -51,6 +62,20 @@ func Amber(fs interface{}, extension string) *AmberEngine {
 			LineNumbers:       false,
 			VirtualFilesystem: fileSystem,
 		},
+		bufPool: &sync.Pool{New: func() interface{} {
+			return new(bytes.Buffer)
+		}},
+	}
+
+	builtinFuncs := template.FuncMap{
+		"render": func(name string, binding interface{}) (template.HTML, error) {
+			result, err := s.executeTemplateBuf(name, binding)
+			return template.HTML(result), err
+		},
+	}
+
+	for k, v := range builtinFuncs {
+		amber.FuncMap[k] = v
 	}
 
 	return s
@@ -86,6 +111,14 @@ func (s *AmberEngine) Reload(developmentMode bool) *AmberEngine {
 	return s
 }
 
+// SetPrettyPrint if pretty printing is enabled.
+// Pretty printing ensures that the output html is properly indented and in human readable form.
+// Defaults to false, response is minified.
+func (s *AmberEngine) SetPrettyPrint(pretty bool) *AmberEngine {
+	s.Options.PrettyPrint = true
+	return s
+}
+
 // AddFunc adds the function to the template's function map.
 // It is legal to overwrite elements of the default actions:
 // - url func(routeName string, args ...string) string
@@ -157,18 +190,11 @@ func (s *AmberEngine) ParseTemplate(name string, contents []byte) error {
 
 	name = strings.TrimPrefix(name, "/")
 
-	/* Sadly, this does not work, only builtin amber.FuncMap
-	can be executed as function, the rest are compiled as data (prepends a "call"),
-	relative code:
-	https://github.com/eknkc/amber/blob/cdade1c073850f4ffc70a829e31235ea6892853b/compiler.go#L771-L794
-
-	tmpl := template.New(name).Funcs(amber.FuncMap).Funcs(s.funcs)
-	if len(funcs) > 0 {
-		tmpl.Funcs(funcs)
-	}
-
-	We can't add them as binding data of map type
-	because those data can be a struct by the caller and we don't want to messup.
+	/*
+		New(...).Funcs(s.builtinFuncs):
+		This won't work on amber, it loads only amber.FuncMap which is global.
+		Relative code:
+		https://github.com/eknkc/amber/blob/cdade1c073850f4ffc70a829e31235ea6892853b/compiler.go#L771-L794
 	*/
 
 	tmpl := template.New(name).Funcs(amber.FuncMap)
@@ -180,6 +206,22 @@ func (s *AmberEngine) ParseTemplate(name string, contents []byte) error {
 	return err
 }
 
+func (s *AmberEngine) executeTemplateBuf(name string, binding interface{}) (string, error) {
+	buf := s.bufPool.Get().(*bytes.Buffer)
+	buf.Reset()
+
+	tmpl := s.fromCache(name)
+	if tmpl == nil {
+		s.bufPool.Put(buf)
+		return "", ErrNotExist{name, false}
+	}
+
+	err := tmpl.ExecuteTemplate(buf, name, binding)
+	result := strings.TrimSuffix(buf.String(), "\n") // on amber it adds a new line.
+	s.bufPool.Put(buf)
+	return result, err
+}
+
 func (s *AmberEngine) fromCache(relativeName string) *template.Template {
 	if s.reload {
 		s.rmu.RLock()

view/django.go

@@ -286,7 +286,7 @@ func (s *DjangoEngine) fromCache(relativeName string) *pongo2.Template {
 
 // ExecuteWriter executes a templates and write its results to the w writer
 // layout here is useless.
-func (s *DjangoEngine) ExecuteWriter(w io.Writer, filename string, layout string, bindingData interface{}) error {
+func (s *DjangoEngine) ExecuteWriter(w io.Writer, filename string, _ string, bindingData interface{}) error {
 	// re-parse the templates if reload is enabled.
 	if s.reload {
 		if err := s.Load(); err != nil {

view/html.go

@@ -36,6 +36,7 @@ type HTMLEngine struct {
 	middleware  func(name string, contents []byte) (string, error)
 	Templates   *template.Template
 	customCache []customTmp // required to load them again if reload is true.
+	bufPool     *sync.Pool
 	//
 }
 
@@ -92,6 +93,9 @@ func HTML(fs interface{}, extension string) *HTMLEngine {
 		layout:      "",
 		layoutFuncs: make(template.FuncMap),
 		funcs:       make(template.FuncMap),
+		bufPool: &sync.Pool{New: func() interface{} {
+			return new(bytes.Buffer)
+		}},
 	}
 
 	return s
@@ -322,11 +326,14 @@ func (s *HTMLEngine) initRootTmpl() { // protected by the caller.
 	}
 }
 
-func (s *HTMLEngine) executeTemplateBuf(name string, binding interface{}) (*bytes.Buffer, error) {
-	buf := new(bytes.Buffer)
-	err := s.Templates.ExecuteTemplate(buf, name, binding)
+func (s *HTMLEngine) executeTemplateBuf(name string, binding interface{}) (string, error) {
+	buf := s.bufPool.Get().(*bytes.Buffer)
+	buf.Reset()
 
-	return buf, err
+	err := s.Templates.ExecuteTemplate(buf, name, binding)
+	result := buf.String()
+	s.bufPool.Put(buf)
+	return result, err
 }
 
 func (s *HTMLEngine) layoutFuncsFor(lt *template.Template, name string, binding interface{}) {
@@ -334,9 +341,9 @@ func (s *HTMLEngine) layoutFuncsFor(lt *template.Template, name string, binding
 
 	funcs := template.FuncMap{
 		"yield": func() (template.HTML, error) {
-			buf, err := s.executeTemplateBuf(name, binding)
+			result, err := s.executeTemplateBuf(name, binding)
 			// Return safe HTML here since we are rendering our own template.
-			return template.HTML(buf.String()), err
+			return template.HTML(result), err
 		},
 	}
 
@@ -352,11 +359,11 @@ func (s *HTMLEngine) runtimeFuncsFor(t *template.Template, name string, binding
 		"part": func(partName string) (template.HTML, error) {
 			nameTemp := strings.Replace(name, s.extension, "", -1)
 			fullPartName := fmt.Sprintf("%s-%s", nameTemp, partName)
-			buf, err := s.executeTemplateBuf(fullPartName, binding)
+			result, err := s.executeTemplateBuf(fullPartName, binding)
 			if err != nil {
 				return "", nil
 			}
-			return template.HTML(buf.String()), err
+			return template.HTML(result), err
 		},
 		"current": func() (string, error) {
 			return name, nil
@@ -364,8 +371,8 @@ func (s *HTMLEngine) runtimeFuncsFor(t *template.Template, name string, binding
 		"partial": func(partialName string) (template.HTML, error) {
 			fullPartialName := fmt.Sprintf("%s-%s", partialName, name)
 			if s.Templates.Lookup(fullPartialName) != nil {
-				buf, err := s.executeTemplateBuf(fullPartialName, binding)
-				return template.HTML(buf.String()), err
+				result, err := s.executeTemplateBuf(fullPartialName, binding)
+				return template.HTML(result), err
 			}
 			return "", nil
 		},
@@ -378,14 +385,14 @@ func (s *HTMLEngine) runtimeFuncsFor(t *template.Template, name string, binding
 			root := name[:len(name)-len(ext)]
 			fullPartialName := fmt.Sprintf("%s%s%s", root, partialName, ext)
 			if s.Templates.Lookup(fullPartialName) != nil {
-				buf, err := s.executeTemplateBuf(fullPartialName, binding)
-				return template.HTML(buf.String()), err
+				result, err := s.executeTemplateBuf(fullPartialName, binding)
+				return template.HTML(result), err
 			}
 			return "", nil
 		},
 		"render": func(fullPartialName string) (template.HTML, error) {
-			buf, err := s.executeTemplateBuf(fullPartialName, binding)
-			return template.HTML(buf.String()), err
+			result, err := s.executeTemplateBuf(fullPartialName, binding)
+			return template.HTML(result), err
 		},
 	}
 

view/jet.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"io"
 	"net/http"
+	"os"
 	"path/filepath"
 	"reflect"
 	"strings"
@@ -18,9 +19,10 @@ const jetEngineName = "jet"
 
 // JetEngine is the jet template parser's view engine.
 type JetEngine struct {
-	fs        http.FileSystem
-	rootDir   string
-	extension string
+	fs          http.FileSystem
+	rootDir     string
+	extension   string
+	left, right string
 
 	loader jet.Loader
 
@@ -72,6 +74,7 @@ func Jet(fs interface{}, extension string) *JetEngine {
 	}
 
 	s := &JetEngine{
+		fs:                getFS(fs),
 		rootDir:           "/",
 		extension:         extension,
 		loader:            &jetLoader{fs: getFS(fs)},
@@ -109,7 +112,8 @@ func (s *JetEngine) Ext() string {
 // corresponding default: {{ or }}.
 // Should act before `Load` or `iris.Application#RegisterView`.
 func (s *JetEngine) Delims(left, right string) *JetEngine {
-	s.Set.Delims(left, right)
+	s.left = left
+	s.right = right
 	return s
 }
 
@@ -217,12 +221,24 @@ func (l *jetLoader) Exists(name string) (string, bool) {
 
 // Load should load the templates from a physical system directory or by an embedded one (assets/go-bindata).
 func (s *JetEngine) Load() error {
-	s.initSet()
-	// Note that, unlike the rest of template engines implementations,
-	// we don't call the Set.GetTemplate to parse the templates,
-	// we let it to the jet template parser itself which does that at serve-time and caches each template by itself.
+	return walk(s.fs, s.rootDir, func(path string, info os.FileInfo, err error) error {
+		if info == nil || info.IsDir() {
+			return nil
+		}
 
-	return nil
+		if s.extension != "" {
+			if !strings.HasSuffix(path, s.extension) {
+				return nil
+			}
+		}
+
+		buf, err := asset(s.fs, path)
+		if err != nil {
+			return fmt.Errorf("%s: %w", path, err)
+		}
+
+		return s.ParseTemplate(path, string(buf))
+	})
 }
 
 // ParseTemplate accepts a name and contnets to parse and cache a template.
@@ -238,6 +254,7 @@ func (s *JetEngine) initSet() {
 	s.mu.Lock()
 	if s.Set == nil {
 		s.Set = jet.NewHTMLSetLoader(s.loader)
+		s.Set.Delims(s.left, s.right)
 		if s.developmentMode && !isNoOpFS(s.fs) {
 			// this check is made to avoid jet's fs lookup on noOp fs (nil passed by the developer).
 			// This can be produced when nil fs passed