Go实战--golang中使用echo嵌入静态资源(labstack/echo、GeertJoh

生命不止，继续 go go go !!!

使用 Go 开发应用的时候，有时会遇到需要读取静态资源的情况。比如开发 Web 应用，程序需要加载模板文件生成输出的 HTML。在程序部署的时候，除了发布应用可执行文件外，还需要发布依赖的静态资源文件。这给发布过程添加了一些麻烦。既然发布单独一个可执行文件是非常简单的操作，就有人会想办法把静态资源文件打包进 Go 的程序文件中。

参考地址：
http://fuxiaohei.me/2016/10/1/go-binary-embed-asset.html

文中提到了：
go-bindata
go.rice
esc

本片博客只会介绍go.rice，其余的会之后进行介绍的。

What’s an Embedded Resource?
An embedded resource in a application is a file that is included as part of the application. The file is not compiled,but is accessable from the code at run-time. Embedded resources can be any file type.

Languages as JAVA and C# support resources out of box. However,this is not the case for Golang. In order to emebed resource,we need to develop our own solution. Thankfully,there are couple of tools that are doing this for us.

参考地址：
http://blog.ralch.com/tutorial/golang-embedded-resources/

go.rice

go.rice is a Go package that makes working with resources such as html,js,css,images,templates,etc very easy.

github地址：
https://github.com/GeertJohan/go.rice

Star: 1107

获取：

go get github.com/GeertJohan/go.rice
go get github.com/GeertJohan/go.rice/rice

FindBox
funcation to access a particular resource bundler (directory).
The function is finding the correct absolute path for your resource files.

// find a rice.Box
templateBox,err := rice.FindBox("your-resource-directory")
if err != nil {
    log.Fatal(err)
}
// get file contents as string
tmpl,err := templateBox.String("your_asset.tmpl")
if err != nil {
    log.Fatal(err)
}

Embedded resource as source code
作为源码嵌入资源
命令：

rice embed-go

生成文件：

<directory-name>.rice-box.go

Embedded resource as an archive
appends a resource as a zip file to already built executable
以zip的形式附加到已经存在的可执行文件

Embedded resource as an syso resource
This is experimental method that generates .syso file that is compiled by Go compiler. The following command generates the coff syso resource files per directory:

rice embed-syso

go build -o <program>
rice append --exec <program>

echo中使用go.rice

代码main.go:

package main

import (
    "net/http"

    "github.com/GeertJohan/go.rice"
    "github.com/labstack/echo"
)

func main() {
    e := echo.New()
    // the file server for rice. "app" is the folder where the files come from.
    assetHandler := http.FileServer(rice.MustFindBox("app").HTTPBox())
    // serves the index.html from rice
    e.GET("/",echo.WrapHandler(assetHandler))

    // servers other static files
    e.GET("/static/*",echo.WrapHandler(http.StripPrefix("/static/",assetHandler)))

    e.Logger.Fatal(e.Start(":1323"))
}

跟main.go同一级，新建一个文件夹app，放入文件file.txt

执行：

rice embed-go

生成了 rice-box.go：

package main

import (
    "github.com/GeertJohan/go.rice/embedded"
    "time"
)

func init() {

    // define files
    file2 := &embedded.EmbeddedFile{
        Filename:    "file.txt",FileModTime: time.Unix(1511406219, 0),Content:     string(""),}

    // define dirs
    dir1 := &embedded.EmbeddedDir{
        Filename:   "",DirModTime: time.Unix(1511406219,ChildFiles: []*embedded.EmbeddedFile{
            file2,// "file.txt"

        },}

    // link ChildDirs
    dir1.ChildDirs = []*embedded.EmbeddedDir{}

    // register embeddedBox
    embedded.RegisterEmbeddedBox(`app`,&embedded.EmbeddedBox{
        Name: `app`,Time: time.Unix(1511406219,Dirs: map[string]*embedded.EmbeddedDir{
            "": dir1,},Files: map[string]*embedded.EmbeddedFile{
            "file.txt": file2,})
}

执行：

go build

生成文件：embed_resources.exe

运行embed_resources.exe
删除app文件夹下的file.txt
浏览器访问http://localhost:1323/
可以看到file.txt文件