Awesome
htmlgo
Type safe and modularize way to generate html on server side.
Download the package with go get -v github.com/theplant/htmlgo and import the package with . gives you simpler code:
import (
. "github.com/theplant/htmlgo"
)
also checkout full API documentation at: <a href="https://godoc.org/github.com/theplant/htmlgo">https://godoc.org/github.com/theplant/htmlgo</a>
Create a simple div, Text will be escaped by html
banner := "We write html in Go"
comp := Div(
Text("123<h1>"),
Textf("Hello, %s", banner),
Br(),
)
Fprint(os.Stdout, comp, context.TODO())
//Output:
// <div>123<h1>Hello, We write html in Go
// <br></div>
Create a full html page
comp := HTML(
Head(
Meta().Charset("utf8"),
Title("My test page"),
),
Body(
Img("images/firefox-icon.png").Alt("My test image"),
),
)
Fprint(os.Stdout, comp, context.TODO())
//Output:
// <!DOCTYPE html>
//
// <html>
// <head>
// <meta charset='utf8'></meta>
//
// <title>My test page</title>
// </head>
//
// <body>
// <img src='images/firefox-icon.png' alt='My test image'></img>
// </body>
// </html>
Use RawHTML and Component
userProfile := func(username string, avatarURL string) HTMLComponent {
return ComponentFunc(func(ctx context.Context) (r []byte, err error) {
return Div(
H1(username).Class("profileName"),
Img(avatarURL).Class("profileImage"),
RawHTML("<svg>complicated svg</svg>\n"),
).Class("userProfile").MarshalHTML(ctx)
})
}
comp := Ul(
Li(
userProfile("felix<h1>", "http://image.com/img1.png"),
),
Li(
userProfile("john", "http://image.com/img2.png"),
),
)
Fprint(os.Stdout, comp, context.TODO())
//Output:
// <ul>
// <li>
// <div class='userProfile'>
// <h1 class='profileName'>felix<h1></h1>
//
// <img src='http://image.com/img1.png' class='profileImage'></img>
// <svg>complicated svg</svg>
// </div>
// </li>
//
// <li>
// <div class='userProfile'>
// <h1 class='profileName'>john</h1>
//
// <img src='http://image.com/img2.png' class='profileImage'></img>
// <svg>complicated svg</svg>
// </div>
// </li>
// </ul>
More complicated customized component
/*
Define MySelect as follows:
type MySelectBuilder struct {
options [][]string
selected string
}
func MySelect() *MySelectBuilder {
return &MySelectBuilder{}
}
func (b *MySelectBuilder) Options(opts [][]string) (r *MySelectBuilder) {
b.options = opts
return b
}
func (b *MySelectBuilder) Selected(selected string) (r *MySelectBuilder) {
b.selected = selected
return b
}
func (b *MySelectBuilder) MarshalHTML(ctx context.Context) (r []byte, err error) {
opts := []HTMLComponent{}
for _, op := range b.options {
var opt HTMLComponent
if op[0] == b.selected {
opt = Option(op[1]).Value(op[0]).Attr("selected", "true")
} else {
opt = Option(op[1]).Value(op[0])
}
opts = append(opts, opt)
}
return Select(opts...).MarshalHTML(ctx)
}
*/
comp := MySelect().Options([][]string{
{"1", "label 1"},
{"2", "label 2"},
{"3", "label 3"},
}).Selected("2")
Fprint(os.Stdout, comp, context.TODO())
//Output:
// <select>
// <option value='1'>label 1</option>
//
// <option value='2' selected='true'>label 2</option>
//
// <option value='3'>label 3</option>
// </select>
Write a little bit of JavaScript and stylesheet
comp := Div(
Button("Hello").Id("hello"),
Style(`
.container {
background-color: red;
}
`),
Script(`
var b = document.getElementById("hello")
b.onclick = function(e){
alert("Hello");
}
`),
).Class("container")
Fprint(os.Stdout, comp, context.TODO())
//Output:
// <div class='container'>
// <button id='hello'>Hello</button>
//
// <style type='text/css'>
// .container {
// background-color: red;
// }
// </style>
//
// <script type='text/javascript'>
// var b = document.getElementById("hello")
// b.onclick = function(e){
// alert("Hello");
// }
// </script>
// </div>
An example about how to integrate into http.Handler, and how to do layout, and how to use context.
type User struct {
Name string
}
userStatus := func() HTMLComponent {
return ComponentFunc(func(ctx context.Context) (r []byte, err error) {
if currentUser, ok := ctx.Value("currentUser").(*User); ok {
return Div(
Text(currentUser.Name),
).Class("username").MarshalHTML(ctx)
}
return Div(Text("Login")).Class("login").MarshalHTML(ctx)
})
}
myHeader := func() HTMLComponent {
return Div(
Text("header"),
userStatus(),
).Class("header")
}
myFooter := func() HTMLComponent {
return Div(Text("footer")).Class("footer")
}
layout := func(in HTMLComponent) (out HTMLComponent) {
out = HTML(
Head(
Meta().Charset("utf8"),
),
Body(
myHeader(),
in,
myFooter(),
),
)
return
}
getLoginUserFromCookie := func(r *http.Request) *User {
return &User{Name: "felix"}
}
homeHandler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
user := getLoginUserFromCookie(r)
ctx := context.WithValue(context.TODO(), "currentUser", user)
root := Div(
Text("This is my home page"),
)
Fprint(w, layout(root), ctx)
})
w := httptest.NewRecorder()
r := httptest.NewRequest("GET", "/", nil)
homeHandler.ServeHTTP(w, r)
fmt.Println(w.Body.String())
//Output:
// <!DOCTYPE html>
//
// <html>
// <head>
// <meta charset='utf8'></meta>
// </head>
//
// <body>
// <div class='header'>header
// <div class='username'>felix</div>
// </div>
//
// <div>This is my home page</div>
//
// <div class='footer'>footer</div>
// </body>
// </html>
An example show how to set different type of attributes
type MoreData struct {
Name string
Count int
}
comp := Div(
Input("username").
Type("checkbox").
Attr("checked", true).
Attr("more-data", &MoreData{Name: "felix", Count: 100}).
Attr("max-length", 10),
Input("username2").
Type("checkbox").
Attr("checked", false),
)
Fprint(os.Stdout, comp, context.TODO())
//Output:
// <div>
// <input name='username' type='checkbox' checked more-data='{"Name":"felix","Count":100}' max-length='10'></input>
//
// <input name='username2' type='checkbox'></input>
// </div>
An example show how to set styles
comp := Div().
StyleIf("background-color:red; border:1px solid red;", true).
StyleIf("color:blue", true)
Fprint(os.Stdout, comp, context.TODO())
//Output:
// <div style='background-color:red; border:1px solid red; color:blue;'></div>
An example to use If, Iff is for body to passed in as an func for the body depends on if condition not to be nil, If is for directly passed in HTMLComponent
type Person struct {
Age int
}
var p *Person
name := "Leon"
comp := Div(
Iff(p != nil && p.Age > 18, func() HTMLComponent {
return Div().Text(name + ": Age > 18")
}).ElseIf(p == nil, func() HTMLComponent {
return Div().Text("No person named " + name)
}).Else(func() HTMLComponent {
return Div().Text(name + ":Age <= 18")
}),
)
Fprint(os.Stdout, comp, context.TODO())
//Output:
// <div>
// <div>No person named Leon</div>
// </div>