gf/os/gview/gview.go

// Copyright 2017 gf Author(https://github.com/gogf/gf). All Rights Reserved.
//
// This Source Code Form is subject to the terms of the MIT License.
// If a copy of the MIT was not distributed with this file,
// You can obtain one at https://github.com/gogf/gf.

// Package gview implements a template engine based on text/template.
//
// Reserved template variable names:
//     I18nLanguage: Assign this variable to define i18n language for each page.
package gview

import (
	"github.com/gogf/gf/container/gmap"
	"github.com/gogf/gf/i18n/gi18n"
	"github.com/gogf/gf/internal/intlog"

	"github.com/gogf/gf"
	"github.com/gogf/gf/container/garray"
	"github.com/gogf/gf/internal/cmdenv"
	"github.com/gogf/gf/os/gfile"
	"github.com/gogf/gf/os/glog"
)

// View object for template engine.
type View struct {
	paths        *garray.StrArray       // Searching array for path, NOT concurrent-safe for performance purpose.
	data         map[string]interface{} // Global template variables.
	funcMap      map[string]interface{} // Global template function map.
	fileCacheMap *gmap.StrAnyMap        // File cache map.
	defaultFile  string                 // Default template file for parsing.
	i18nManager  *gi18n.Manager         // I18n manager for this view.
	delimiters   []string               // Custom template delimiters.
	config       Config                 // Extra configuration for the view.
}

// Params is type for template params.
type Params = map[string]interface{}

// FuncMap is type for custom template functions.
type FuncMap = map[string]interface{}

const (
	// Default template file for parsing.
	defaultParsingFile = "index.html"
)

var (
	// Default view object.
	defaultViewObj *View
)

// checkAndInitDefaultView checks and initializes the default view object.
// The default view object will be initialized just once.
func checkAndInitDefaultView() {
	if defaultViewObj == nil {
		defaultViewObj = New()
	}
}

// ParseContent parses the template content directly using the default view object
// and returns the parsed content.
func ParseContent(content string, params Params) (string, error) {
	checkAndInitDefaultView()
	return defaultViewObj.ParseContent(content, params)
}

// New returns a new view object.
// The parameter <path> specifies the template directory path to load template files.
func New(path ...string) *View {
	view := &View{
		paths:        garray.NewStrArray(),
		data:         make(map[string]interface{}),
		funcMap:      make(map[string]interface{}),
		fileCacheMap: gmap.NewStrAnyMap(true),
		defaultFile:  defaultParsingFile,
		i18nManager:  gi18n.Instance(),
		delimiters:   make([]string, 2),
	}
	if len(path) > 0 && len(path[0]) > 0 {
		if err := view.SetPath(path[0]); err != nil {
			intlog.Error(err)
		}
	} else {
		// Customized dir path from env/cmd.
		if envPath := cmdenv.Get("gf.gview.path").String(); envPath != "" {
			if gfile.Exists(envPath) {
				if err := view.SetPath(envPath); err != nil {
					intlog.Error(err)
				}
			} else {
				if errorPrint() {
					glog.Errorf("Template directory path does not exist: %s", envPath)
				}
			}
		} else {
			// Dir path of working dir.
			if err := view.SetPath(gfile.Pwd()); err != nil {
				intlog.Error(err)
			}
			// Dir path of binary.
			if selfPath := gfile.SelfDir(); selfPath != "" && gfile.Exists(selfPath) {
				if err := view.AddPath(selfPath); err != nil {
					intlog.Error(err)
				}
			}
			// Dir path of main package.
			if mainPath := gfile.MainPkgPath(); mainPath != "" && gfile.Exists(mainPath) {
				if err := view.AddPath(mainPath); err != nil {
					intlog.Error(err)
				}
			}
		}
	}
	view.SetDelimiters("{{", "}}")
	// default build-in variables.
	view.data["GF"] = map[string]interface{}{
		"version": gf.VERSION,
	}
	// default build-in functions.
	view.BindFunc("eq", view.funcEq)
	view.BindFunc("ne", view.funcNe)
	view.BindFunc("lt", view.funcLt)
	view.BindFunc("le", view.funcLe)
	view.BindFunc("gt", view.funcGt)
	view.BindFunc("ge", view.funcGe)
	view.BindFunc("text", view.funcText)

	view.BindFunc("html", view.funcHtmlEncode)
	view.BindFunc("htmlencode", view.funcHtmlEncode)
	view.BindFunc("htmldecode", view.funcHtmlDecode)
	view.BindFunc("encode", view.funcHtmlEncode)
	view.BindFunc("decode", view.funcHtmlDecode)

	view.BindFunc("url", view.funcUrlEncode)
	view.BindFunc("urlencode", view.funcUrlEncode)
	view.BindFunc("urldecode", view.funcUrlDecode)
	view.BindFunc("date", view.funcDate)
	view.BindFunc("substr", view.funcSubStr)
	view.BindFunc("strlimit", view.funcStrLimit)
	view.BindFunc("concat", view.funcConcat)
	view.BindFunc("replace", view.funcReplace)
	view.BindFunc("compare", view.funcCompare)
	view.BindFunc("hidestr", view.funcHideStr)
	view.BindFunc("highlight", view.funcHighlight)
	view.BindFunc("toupper", view.funcToUpper)
	view.BindFunc("tolower", view.funcToLower)
	view.BindFunc("nl2br", view.funcNl2Br)
	view.BindFunc("include", view.funcInclude)
	view.BindFunc("dump", view.funcDump)
	return view
}