Simple, lightweight and faster response (JSON, JSONP, XML, YAML, HTML, File) rendering package for Go

Published Nov 18, 2017
Simple, lightweight and faster response (JSON, JSONP, XML, YAML, HTML, File) rendering package for Go

Package renderer

Simple, lightweight and faster response (JSON, JSONP, XML, YAML, HTML, File) rendering package for Go

Installation

Install the package using

$ go get github.com/thedevsaddam/renderer/...

Usage

To use the package import it in your *.go code

import "github.com/thedevsaddam/renderer"

Example

package main

import (
  "io"
  "log"
  "net/http"
  "os"

  "github.com/thedevsaddam/renderer"
)

func main() {
  rnd := renderer.New()

  mux := http.NewServeMux()

  usr := struct {
    Name string
    Age  int
  }{"John Doe", 30}

  // serving String as text/plain
  mux.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
    rnd.String(w, http.StatusOK, "Welcome to renderer")
  })

  // serving success but no content
  mux.HandleFunc("/no-content", func(w http.ResponseWriter, r *http.Request) {
    rnd.NoContent(w)
  })

  // serving JSON
  mux.HandleFunc("/json", func(w http.ResponseWriter, r *http.Request) {
    rnd.JSON(w, http.StatusOK, usr)
  })

  // serving JSONP
  mux.HandleFunc("/jsonp", func(w http.ResponseWriter, r *http.Request) {
    rnd.JSONP(w, http.StatusOK, "callback", usr)
  })

  // serving XML
  mux.HandleFunc("/xml", func(w http.ResponseWriter, r *http.Request) {
    rnd.XML(w, http.StatusOK, usr)
  })

  // serving YAML
  mux.HandleFunc("/yaml", func(w http.ResponseWriter, r *http.Request) {
    rnd.YAML(w, http.StatusOK, usr)
  })

  // serving File as arbitary binary data
  mux.HandleFunc("/binary", func(w http.ResponseWriter, r *http.Request) {
    var reader io.Reader
    reader, _ = os.Open("../README.md")
    rnd.Binary(w, http.StatusOK, reader, "readme.md", true)
  })

  // serving File as inline
  mux.HandleFunc("/file-inline", func(w http.ResponseWriter, r *http.Request) {
    rnd.FileView(w, http.StatusOK, "../README.md", "readme.md")
  })

  // serving File as attachment
  mux.HandleFunc("/file-download", func(w http.ResponseWriter, r *http.Request) {
    rnd.FileDownload(w, http.StatusOK, "../README.md", "readme.md")
  })

  // serving File from reader as inline
  mux.HandleFunc("/file-reader", func(w http.ResponseWriter, r *http.Request) {
    var reader io.Reader
    reader, _ = os.Open("../README.md")
    rnd.File(w, http.StatusOK, reader, "readme.md", true)
  })

  // serving custom response using render and chaining methods
  mux.HandleFunc("/render", func(w http.ResponseWriter, r *http.Request) {
    w.Header().Set(renderer.ContentType, renderer.ContentText)
    rnd.Render(w, http.StatusOK, []byte("Send the message as text response"))
  })

  port := ":9000"
  log.Println("Listening on port", port)
  http.ListenAndServe(port, mux)
}

How to render html template?

Well, you can parse html template using HTML, View, Template any of these method. These are based on html/template package.

When using Template method you can simply pass the base layouts, templates path as a slice of string.

Template example

You can parse template on the fly using Template method. You can set delimiter, inject FuncMap easily.

template/layout.tmpl

<html>
  <head>
    <title>{{ template "title" . }}</title>
  </head>
  <body>
    {{ template "content" . }}
  </body>
  {{ block "sidebar" .}}{{end}}
</html>

template/index.tmpl

{{ define "title" }}Home{{ end }}

{{ define "content" }}
  <h1>Hello, {{ .Name | toUpper }}</h1>
  <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit.</p>
{{ end }}

template/partial.tmpl

{{define "sidebar"}}
  simple sidebar code
{{end}}

template.go

package main

import (
  "html/template"
  "log"
  "net/http"
  "strings"

  "github.com/thedevsaddam/renderer"
)

var rnd *renderer.Render

func init() {
  rnd = renderer.New()
}

func toUpper(s string) string {
  return strings.ToUpper(s)
}

func handler(w http.ResponseWriter, r *http.Request) {
  usr := struct {
    Name string
    Age  int
  }{"john doe", 30}

  tpls := []string{"template/layout.tmpl", "template/index.tmpl", "template/partial.tmpl"}
  rnd.FuncMap(template.FuncMap{
    "toUpper": toUpper,
  })
  err := rnd.Template(w, http.StatusOK, tpls, usr)
  if err != nil {
    log.Fatal(err) //respond with error page or message
  }
}

func main() {
  http.HandleFunc("/", handler)
  log.Println("Listening port: 9000")
  http.ListenAndServe(":9000", nil)
}

HTML example

When using HTML you can parse a template directory using pattern and call the template by their name. See the example code below:

html/index.html

{{define "indexPage"}}
    <html>
    {{template "header"}}
    <body>
        <h3>Index</h3>
        <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit</p>
    </body>
    {{template "footer"}}
    </html>
{{end}}

html/header.html

{{define "header"}}
     <head>
         <title>Header</title>
         <h1>Header section</h1>
     </head>
{{end}}

html/footer.html

{{define "footer"}}
     <footer>Copyright &copy; 2020</footer>
{{end}}

html.go

package main

import (
  "log"
  "net/http"

  "github.com/thedevsaddam/renderer"
)

var rnd *renderer.Render

func init() {
  rnd = renderer.New(
    renderer.Options{
      ParseGlobPattern: "html/*.html",
    },
  )
}

func handler(w http.ResponseWriter, r *http.Request) {
  err := rnd.HTML(w, http.StatusOK, "indexPage", nil)
  if err != nil {
    log.Fatal(err)
  }
}

func main() {
  http.HandleFunc("/", handler)
  log.Println("Listening port: 9000")
  http.ListenAndServe(":9000", nil)
}

View example

When using View for parsing template you can pass multiple layout and templates. Here template name will be the file name. See the example to get the idea.

view/base.lout

<html>
  <head>
     <title>{{block "title" .}} {{end}}</title>
  </head>
  <body>
    {{ template "content" . }}
  </body>
</html>

view/home.tpl

{{define "title"}}Home{{end}}
{{define "content"}}
<h3>Home page</h3>
    <ul>
        <li><a href="/">Home</a></li>
        <li><a href="/about">About Me</a></li>
    </ul>
    <p>
    Lorem ipsum dolor sit amet</p>
{{end}}

view/about.tpl

{{define "title"}}About Me{{end}}
{{define "content"}}
<h2>This is About me page.</h2>
<ul>
    Lorem ipsum dolor sit amet, consectetur adipisicing elit,
</ul>
<p><a href="/">Home</a></p>
{{end}}

view.go

package main

import (
  "log"
  "net/http"

  "github.com/thedevsaddam/renderer"
)

var rnd *renderer.Render

func init() {
  rnd = renderer.New(renderer.Options{
    TemplateDir: "view",
  })
}

func home(w http.ResponseWriter, r *http.Request) {
  err := rnd.View(w, http.StatusOK, "home", nil)
  if err != nil {
    log.Fatal(err)
  }
}

func about(w http.ResponseWriter, r *http.Request) {
  err := rnd.View(w, http.StatusOK, "about", nil)
  if err != nil {
    log.Fatal(err)
  }
}

func main() {
  http.HandleFunc("/", home)
  http.HandleFunc("/about", about)
  log.Println("Listening port: 9000\n / is root \n /about is about page")
  http.ListenAndServe(":9000", nil)
}

Note: This is a wrapper on top of go built-in packages to provide syntactic sugar.

Contribution

Your suggestions will be more than appreciated.
Read the contribution guide here

See all contributors

Read API doc to know about Available options and Methods

License

The renderer is an open-source software licensed under the MIT License.

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