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# Gin Web Framework

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<img align="right" width="159px" src="https://raw.githubusercontent.com/gin-gonic/logo/master/color.png">
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[![Build Status](https://travis-ci.org/gin-gonic/gin.svg)](https://travis-ci.org/gin-gonic/gin)
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[![codecov](https://codecov.io/gh/gin-gonic/gin/branch/master/graph/badge.svg)](https://codecov.io/gh/gin-gonic/gin)
[![Go Report Card](https://goreportcard.com/badge/github.com/gin-gonic/gin)](https://goreportcard.com/report/github.com/gin-gonic/gin)
[![GoDoc](https://godoc.org/github.com/gin-gonic/gin?status.svg)](https://godoc.org/github.com/gin-gonic/gin)
[![Join the chat at https://gitter.im/gin-gonic/gin](https://badges.gitter.im/Join%20Chat.svg)](https://gitter.im/gin-gonic/gin?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
[![Sourcegraph](https://sourcegraph.com/github.com/gin-gonic/gin/-/badge.svg)](https://sourcegraph.com/github.com/gin-gonic/gin?badge)
[![Open Source Helpers](https://www.codetriage.com/gin-gonic/gin/badges/users.svg)](https://www.codetriage.com/gin-gonic/gin)
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Gin is a web framework written in Go (Golang). It features a martini-like API with much better performance, up to 40 times faster thanks to [httprouter](https://github.com/julienschmidt/httprouter). If you need performance and good productivity, you will love Gin.

![Gin console logger](https://gin-gonic.github.io/gin/other/console.png)

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## Contents

- [Installation](#installation)
- [Prerequisite](#prerequisite)
- [Quick start](#quick-start)
- [Benchmarks](#benchmarks)
- [Gin v1.stable](#gin-v1-stable)
- [Build with jsoniter](#build-with-jsoniter)
- [API Examples](#api-examples)
    - [Using GET,POST,PUT,PATCH,DELETE and OPTIONS](#using-get-post-put-patch-delete-and-options)
    - [Parameters in path](#parameters-in-path)
    - [Querystring parameters](#querystring-parameters)
    - [Multipart/Urlencoded Form](#multiparturlencoded-form)
    - [Another example: query + post form](#another-example-query--post-form)
    - [Map as querystring or postform parameters](#map-as-querystring-or-postform-parameters)
    - [Upload files](#upload-files)
    - [Grouping routes](#grouping-routes)
    - [Blank Gin without middleware by default](#blank-gin-without-middleware-by-default)
    - [Using middleware](#using-middleware)
    - [How to write log file](#how-to-write-log-file)
    - [Model binding and validation](#model-binding-and-validation)
    - [Custom Validators](#custom-validators)
    - [Only Bind Query String](#only-bind-query-string)
    - [Bind Query String or Post Data](#bind-query-string-or-post-data)
    - [Bind HTML checkboxes](#bind-html-checkboxes)
    - [Multipart/Urlencoded binding](#multiparturlencoded-binding)
    - [XML, JSON and YAML rendering](#xml-json-and-yaml-rendering)
    - [JSONP rendering](#jsonp)
    - [Serving static files](#serving-static-files)
    - [Serving data from reader](#serving-data-from-reader)
    - [HTML rendering](#html-rendering)
    - [Multitemplate](#multitemplate)
    - [Redirects](#redirects)
    - [Custom Middleware](#custom-middleware)
    - [Using BasicAuth() middleware](#using-basicauth-middleware)
    - [Goroutines inside a middleware](#goroutines-inside-a-middleware)
    - [Custom HTTP configuration](#custom-http-configuration)
    - [Support Let's Encrypt](#support-lets-encrypt)
    - [Run multiple service using Gin](#run-multiple-service-using-gin)
    - [Graceful restart or stop](#graceful-restart-or-stop)
    - [Build a single binary with templates](#build-a-single-binary-with-templates)
    - [Bind form-data request with custom struct](#bind-form-data-request-with-custom-struct)
    - [Try to bind body into different structs](#try-to-bind-body-into-different-structs)
    - [http2 server push](#http2-server-push)
- [Testing](#testing)
- [Users](#users--)

## Installation

To install Gin package, you need to install Go and set your Go workspace first.

1. Download and install it:

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```sh
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$ go get -u github.com/gin-gonic/gin
```

2. Import it in your code:

```go
import "github.com/gin-gonic/gin"
```

3. (Optional) Import `net/http`. This is required for example if using constants such as `http.StatusOK`.

```go
import "net/http"
```

### Use a vendor tool like [Govendor](https://github.com/kardianos/govendor)

1. `go get` govendor

```sh
$ go get github.com/kardianos/govendor
```
2. Create your project folder and `cd` inside

```sh
$ mkdir -p $GOPATH/src/github.com/myusername/project && cd "$_"
```

3. Vendor init your project and add gin

```sh
$ govendor init
$ govendor fetch github.com/gin-gonic/gin@v1.2
```

4. Copy a starting template inside your project

```sh
$ curl https://raw.githubusercontent.com/gin-gonic/gin/master/examples/basic/main.go > main.go
```

5. Run your project

```sh
$ go run main.go
```

## Prerequisite

Now Gin requires Go 1.6 or later and Go 1.7 will be required soon.

## Quick start
 
```sh
# assume the following codes in example.go file
$ cat example.go
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```

```go
package main

import "github.com/gin-gonic/gin"

func main() {
	r := gin.Default()
	r.GET("/ping", func(c *gin.Context) {
		c.JSON(200, gin.H{
			"message": "pong",
		})
	})
	r.Run() // listen and serve on 0.0.0.0:8080
}
```

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```
# run example.go and visit 0.0.0.0:8080/ping on browser
$ go run example.go
```

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## Benchmarks

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Gin uses a custom version of [HttpRouter](https://github.com/julienschmidt/httprouter)
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[See all benchmarks](/BENCHMARKS.md)

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Benchmark name                              | (1)        | (2)         | (3) 		    | (4)
--------------------------------------------|-----------:|------------:|-----------:|---------:
**BenchmarkGin_GithubAll**                  | **30000**  |  **48375**  |     **0**  |   **0**
BenchmarkAce_GithubAll                      |   10000    |   134059    |   13792    |   167
BenchmarkBear_GithubAll                     |    5000    |   534445    |   86448    |   943
BenchmarkBeego_GithubAll                    |    3000    |   592444    |   74705    |   812
BenchmarkBone_GithubAll                     |     200    |  6957308    |  698784    |  8453
BenchmarkDenco_GithubAll                    |   10000    |   158819    |   20224    |   167
BenchmarkEcho_GithubAll                     |   10000    |   154700    |    6496    |   203
BenchmarkGocraftWeb_GithubAll               |    3000    |   570806    |  131656    |  1686
BenchmarkGoji_GithubAll                     |    2000    |   818034    |   56112    |   334
BenchmarkGojiv2_GithubAll                   |    2000    |  1213973    |  274768    |  3712
BenchmarkGoJsonRest_GithubAll               |    2000    |   785796    |  134371    |  2737
BenchmarkGoRestful_GithubAll                |     300    |  5238188    |  689672    |  4519
BenchmarkGorillaMux_GithubAll               |     100    | 10257726    |  211840    |  2272
BenchmarkHttpRouter_GithubAll               |   20000    |   105414    |   13792    |   167
BenchmarkHttpTreeMux_GithubAll              |   10000    |   319934    |   65856    |   671
BenchmarkKocha_GithubAll                    |   10000    |   209442    |   23304    |   843
BenchmarkLARS_GithubAll                     |   20000    |    62565    |       0    |     0
BenchmarkMacaron_GithubAll                  |    2000    |  1161270    |  204194    |  2000
BenchmarkMartini_GithubAll                  |     200    |  9991713    |  226549    |  2325
BenchmarkPat_GithubAll                      |     200    |  5590793    | 1499568    | 27435
BenchmarkPossum_GithubAll                   |   10000    |   319768    |   84448    |   609
BenchmarkR2router_GithubAll                 |   10000    |   305134    |   77328    |   979
BenchmarkRivet_GithubAll                    |   10000    |   132134    |   16272    |   167
BenchmarkTango_GithubAll                    |    3000    |   552754    |   63826    |  1618
BenchmarkTigerTonic_GithubAll               |    1000    |  1439483    |  239104    |  5374
BenchmarkTraffic_GithubAll                  |     100    | 11383067    | 2659329    | 21848
BenchmarkVulcan_GithubAll                   |    5000    |   394253    |   19894    |   609

- (1): Total Repetitions achieved in constant time, higher means more confident result
- (2): Single Repetition Duration (ns/op), lower is better
- (3): Heap Memory (B/op), lower is better
- (4): Average Allocations per Repetition (allocs/op), lower is better
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## Gin v1. stable

- [x] Zero allocation router.
- [x] Still the fastest http router and framework. From routing to writing.
- [x] Complete suite of unit tests
- [x] Battle tested
- [x] API frozen, new releases will not break your code.

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## Build with [jsoniter](https://github.com/json-iterator/go)
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Gin use `encoding/json` as default json package but you can change to [jsoniter](https://github.com/json-iterator/go) by build from other tags.
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```sh
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$ go build -tags=jsoniter .
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```

## API Examples

### Using GET, POST, PUT, PATCH, DELETE and OPTIONS

```go
func main() {
	// Disable Console Color
	// gin.DisableConsoleColor()

	// Creates a gin router with default middleware:
	// logger and recovery (crash-free) middleware
	router := gin.Default()

	router.GET("/someGet", getting)
	router.POST("/somePost", posting)
	router.PUT("/somePut", putting)
	router.DELETE("/someDelete", deleting)
	router.PATCH("/somePatch", patching)
	router.HEAD("/someHead", head)
	router.OPTIONS("/someOptions", options)

	// By default it serves on :8080 unless a
	// PORT environment variable was defined.
	router.Run()
	// router.Run(":3000") for a hard coded port
}
```

### Parameters in path

```go
func main() {
	router := gin.Default()

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	// This handler will match /user/john but will not match /user/ or /user
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	router.GET("/user/:name", func(c *gin.Context) {
		name := c.Param("name")
		c.String(http.StatusOK, "Hello %s", name)
	})

	// However, this one will match /user/john/ and also /user/john/send
	// If no other routers match /user/john, it will redirect to /user/john/
	router.GET("/user/:name/*action", func(c *gin.Context) {
		name := c.Param("name")
		action := c.Param("action")
		message := name + " is " + action
		c.String(http.StatusOK, message)
	})

	router.Run(":8080")
}
```

### Querystring parameters

```go
func main() {
	router := gin.Default()

	// Query string parameters are parsed using the existing underlying request object.
	// The request responds to a url matching:  /welcome?firstname=Jane&lastname=Doe
	router.GET("/welcome", func(c *gin.Context) {
		firstname := c.DefaultQuery("firstname", "Guest")
		lastname := c.Query("lastname") // shortcut for c.Request.URL.Query().Get("lastname")

		c.String(http.StatusOK, "Hello %s %s", firstname, lastname)
	})
	router.Run(":8080")
}
```

### Multipart/Urlencoded Form

```go
func main() {
	router := gin.Default()

	router.POST("/form_post", func(c *gin.Context) {
		message := c.PostForm("message")
		nick := c.DefaultPostForm("nick", "anonymous")

		c.JSON(200, gin.H{
			"status":  "posted",
			"message": message,
			"nick":    nick,
		})
	})
	router.Run(":8080")
}
```

### Another example: query + post form

```
POST /post?id=1234&page=1 HTTP/1.1
Content-Type: application/x-www-form-urlencoded

name=manu&message=this_is_great
```

```go
func main() {
	router := gin.Default()

	router.POST("/post", func(c *gin.Context) {

		id := c.Query("id")
		page := c.DefaultQuery("page", "0")
		name := c.PostForm("name")
		message := c.PostForm("message")

		fmt.Printf("id: %s; page: %s; name: %s; message: %s", id, page, name, message)
	})
	router.Run(":8080")
}
```

```
id: 1234; page: 1; name: manu; message: this_is_great
```

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### Map as querystring or postform parameters

```
POST /post?ids[a]=1234&ids[b]=hello HTTP/1.1
Content-Type: application/x-www-form-urlencoded

names[first]=thinkerou&names[second]=tianou
```

```go
func main() {
	router := gin.Default()

	router.POST("/post", func(c *gin.Context) {

		ids := c.QueryMap("ids")
		names := c.PostFormMap("names")

		fmt.Printf("ids: %v; names: %v", ids, names)
	})
	router.Run(":8080")
}
```

```
ids: map[b:hello a:1234], names: map[second:tianou first:thinkerou]
```

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### Upload files

#### Single file

References issue [#774](https://github.com/gin-gonic/gin/issues/774) and detail [example code](examples/upload-file/single).

```go
func main() {
	router := gin.Default()
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	// Set a lower memory limit for multipart forms (default is 32 MiB)
	// router.MaxMultipartMemory = 8 << 20  // 8 MiB
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	router.POST("/upload", func(c *gin.Context) {
		// single file
		file, _ := c.FormFile("file")
		log.Println(file.Filename)

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		// Upload the file to specific dst.
		// c.SaveUploadedFile(file, dst)

		c.String(http.StatusOK, fmt.Sprintf("'%s' uploaded!", file.Filename))
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	})
	router.Run(":8080")
}
```

How to `curl`:

```bash
curl -X POST http://localhost:8080/upload \
  -F "file=@/Users/appleboy/test.zip" \
  -H "Content-Type: multipart/form-data"
```

#### Multiple files

See the detail [example code](examples/upload-file/multiple).

```go
func main() {
	router := gin.Default()
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	// Set a lower memory limit for multipart forms (default is 32 MiB)
	// router.MaxMultipartMemory = 8 << 20  // 8 MiB
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	router.POST("/upload", func(c *gin.Context) {
		// Multipart form
		form, _ := c.MultipartForm()
		files := form.File["upload[]"]

		for _, file := range files {
			log.Println(file.Filename)
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			// Upload the file to specific dst.
			// c.SaveUploadedFile(file, dst)
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		}
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		c.String(http.StatusOK, fmt.Sprintf("%d files uploaded!", len(files)))
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	})
	router.Run(":8080")
}
```

How to `curl`:

```bash
curl -X POST http://localhost:8080/upload \
  -F "upload[]=@/Users/appleboy/test1.zip" \
  -F "upload[]=@/Users/appleboy/test2.zip" \
  -H "Content-Type: multipart/form-data"
```

### Grouping routes

```go
func main() {
	router := gin.Default()

	// Simple group: v1
	v1 := router.Group("/v1")
	{
		v1.POST("/login", loginEndpoint)
		v1.POST("/submit", submitEndpoint)
		v1.POST("/read", readEndpoint)
	}

	// Simple group: v2
	v2 := router.Group("/v2")
	{
		v2.POST("/login", loginEndpoint)
		v2.POST("/submit", submitEndpoint)
		v2.POST("/read", readEndpoint)
	}

	router.Run(":8080")
}
```

### Blank Gin without middleware by default

Use

```go
r := gin.New()
```

instead of

```go
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// Default With the Logger and Recovery middleware already attached
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r := gin.Default()
```


### Using middleware
```go
func main() {
	// Creates a router without any middleware by default
	r := gin.New()

	// Global middleware
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	// Logger middleware will write the logs to gin.DefaultWriter even if you set with GIN_MODE=release.
	// By default gin.DefaultWriter = os.Stdout
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	r.Use(gin.Logger())
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	// Recovery middleware recovers from any panics and writes a 500 if there was one.
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	r.Use(gin.Recovery())

	// Per route middleware, you can add as many as you desire.
	r.GET("/benchmark", MyBenchLogger(), benchEndpoint)

	// Authorization group
	// authorized := r.Group("/", AuthRequired())
	// exactly the same as:
	authorized := r.Group("/")
	// per group middleware! in this case we use the custom created
	// AuthRequired() middleware just in the "authorized" group.
	authorized.Use(AuthRequired())
	{
		authorized.POST("/login", loginEndpoint)
		authorized.POST("/submit", submitEndpoint)
		authorized.POST("/read", readEndpoint)

		// nested group
		testing := authorized.Group("testing")
		testing.GET("/analytics", analyticsEndpoint)
	}

	// Listen and serve on 0.0.0.0:8080
	r.Run(":8080")
}
```

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### How to write log file
```go
func main() {
    // Disable Console Color, you don't need console color when writing the logs to file.
    gin.DisableConsoleColor()

    // Logging to a file.
    f, _ := os.Create("gin.log")
    gin.DefaultWriter = io.MultiWriter(f)

    // Use the following code if you need to write the logs to file and console at the same time.
    // gin.DefaultWriter = io.MultiWriter(f, os.Stdout)

    router := gin.Default()
    router.GET("/ping", func(c *gin.Context) {
        c.String(200, "pong")
    })

    router.Run(":8080")
}
```

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### Model binding and validation

To bind a request body into a type, use model binding. We currently support binding of JSON, XML and standard form values (foo=bar&boo=baz).

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Gin uses [**go-playground/validator.v8**](https://github.com/go-playground/validator) for validation. Check the full docs on tags usage [here](http://godoc.org/gopkg.in/go-playground/validator.v8#hdr-Baked_In_Validators_and_Tags).

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Note that you need to set the corresponding binding tag on all fields you want to bind. For example, when binding from JSON, set `json:"fieldname"`.

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Also, Gin provides two sets of methods for binding:
- **Type** - Must bind
  - **Methods** - `Bind`, `BindJSON`, `BindQuery`
  - **Behavior** - These methods use `MustBindWith` under the hood. If there is a binding error, the request is aborted with `c.AbortWithError(400, err).SetType(ErrorTypeBind)`. This sets the response status code to 400 and the `Content-Type` header is set to `text/plain; charset=utf-8`. Note that if you try to set the response code after this, it will result in a warning `[GIN-debug] [WARNING] Headers were already written. Wanted to override status code 400 with 422`. If you wish to have greater control over the behavior, consider using the `ShouldBind` equivalent method.
- **Type** - Should bind
  - **Methods** - `ShouldBind`, `ShouldBindJSON`, `ShouldBindQuery`
  - **Behavior** - These methods use `ShouldBindWith` under the hood. If there is a binding error, the error is returned and it is the developer's responsibility to handle the request and error appropriately.

When using the Bind-method, Gin tries to infer the binder depending on the Content-Type header. If you are sure what you are binding, you can use `MustBindWith` or `ShouldBindWith`.
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You can also specify that specific fields are required. If a field is decorated with `binding:"required"` and has a empty value when binding, an error will be returned.
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```go
// Binding from JSON
type Login struct {
	User     string `form:"user" json:"user" binding:"required"`
	Password string `form:"password" json:"password" binding:"required"`
}

func main() {
	router := gin.Default()

	// Example for binding JSON ({"user": "manu", "password": "123"})
	router.POST("/loginJSON", func(c *gin.Context) {
		var json Login
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		if err := c.ShouldBindJSON(&json); err == nil {
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			if json.User == "manu" && json.Password == "123" {
				c.JSON(http.StatusOK, gin.H{"status": "you are logged in"})
			} else {
				c.JSON(http.StatusUnauthorized, gin.H{"status": "unauthorized"})
			}
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		} else {
			c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
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		}
	})

	// Example for binding a HTML form (user=manu&password=123)
	router.POST("/loginForm", func(c *gin.Context) {
		var form Login
		// This will infer what binder to use depending on the content-type header.
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		if err := c.ShouldBind(&form); err == nil {
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			if form.User == "manu" && form.Password == "123" {
				c.JSON(http.StatusOK, gin.H{"status": "you are logged in"})
			} else {
				c.JSON(http.StatusUnauthorized, gin.H{"status": "unauthorized"})
			}
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		} else {
			c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
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		}
	})

	// Listen and serve on 0.0.0.0:8080
	router.Run(":8080")
}
```

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**Sample request**
```shell
$ curl -v -X POST \
  http://localhost:8080/loginJSON \
  -H 'content-type: application/json' \
  -d '{ "user": "manu" }'
> POST /loginJSON HTTP/1.1
> Host: localhost:8080
> User-Agent: curl/7.51.0
> Accept: */*
> content-type: application/json
> Content-Length: 18
>
* upload completely sent off: 18 out of 18 bytes
< HTTP/1.1 400 Bad Request
< Content-Type: application/json; charset=utf-8
< Date: Fri, 04 Aug 2017 03:51:31 GMT
< Content-Length: 100
<
{"error":"Key: 'Login.Password' Error:Field validation for 'Password' failed on the 'required' tag"}
```

**Skip validate**

When running the above example using the above the `curl` command, it returns error. Because the example use `binding:"required"` for `Password`. If use `binding:"-"` for `Password`, then it will not return error when running the above example again.

### Custom Validators

It is also possible to register custom validators. See the [example code](examples/custom-validation/server.go).

[embedmd]:# (examples/custom-validation/server.go go)
```go
package main

import (
	"net/http"
	"reflect"
	"time"

	"github.com/gin-gonic/gin"
	"github.com/gin-gonic/gin/binding"
	"gopkg.in/go-playground/validator.v8"
)

type Booking struct {
	CheckIn  time.Time `form:"check_in" binding:"required,bookabledate" time_format:"2006-01-02"`
	CheckOut time.Time `form:"check_out" binding:"required,gtfield=CheckIn" time_format:"2006-01-02"`
}

func bookableDate(
	v *validator.Validate, topStruct reflect.Value, currentStructOrField reflect.Value,
	field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string,
) bool {
	if date, ok := field.Interface().(time.Time); ok {
		today := time.Now()
		if today.Year() > date.Year() || today.YearDay() > date.YearDay() {
			return false
		}
	}
	return true
}

func main() {
	route := gin.Default()

	if v, ok := binding.Validator.Engine().(*validator.Validate); ok {
		v.RegisterValidation("bookabledate", bookableDate)
	}

	route.GET("/bookable", getBookable)
	route.Run(":8085")
}

func getBookable(c *gin.Context) {
	var b Booking
	if err := c.ShouldBindWith(&b, binding.Query); err == nil {
		c.JSON(http.StatusOK, gin.H{"message": "Booking dates are valid!"})
	} else {
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
	}
}
```

```console
$ curl "localhost:8085/bookable?check_in=2018-04-16&check_out=2018-04-17"
{"message":"Booking dates are valid!"}

$ curl "localhost:8085/bookable?check_in=2018-03-08&check_out=2018-03-09"
{"error":"Key: 'Booking.CheckIn' Error:Field validation for 'CheckIn' failed on the 'bookabledate' tag"}
```

[Struct level validations](https://github.com/go-playground/validator/releases/tag/v8.7) can also be registed this way.
See the [struct-lvl-validation example](examples/struct-lvl-validations) to learn more.

### Only Bind Query String

`ShouldBindQuery` function only binds the query params and not the post data. See the [detail information](https://github.com/gin-gonic/gin/issues/742#issuecomment-315953017).

```go
package main

import (
	"log"

	"github.com/gin-gonic/gin"
)

type Person struct {
	Name    string `form:"name"`
	Address string `form:"address"`
}

func main() {
	route := gin.Default()
	route.Any("/testing", startPage)
	route.Run(":8085")
}

func startPage(c *gin.Context) {
	var person Person
	if c.ShouldBindQuery(&person) == nil {
		log.Println("====== Only Bind By Query String ======")
		log.Println(person.Name)
		log.Println(person.Address)
	}
	c.String(200, "Success")
}

```

### Bind Query String or Post Data
722 723 724 725 726 727 728 729

See the [detail information](https://github.com/gin-gonic/gin/issues/742#issuecomment-264681292).

```go
package main

import "log"
import "github.com/gin-gonic/gin"
730
import "time"
731 732

type Person struct {
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	Name     string    `form:"name"`
	Address  string    `form:"address"`
	Birthday time.Time `form:"birthday" time_format:"2006-01-02" time_utc:"1"`
736 737 738 739 740 741 742 743 744 745 746 747
}

func main() {
	route := gin.Default()
	route.GET("/testing", startPage)
	route.Run(":8085")
}

func startPage(c *gin.Context) {
	var person Person
	// If `GET`, only `Form` binding engine (`query`) used.
	// If `POST`, first checks the `content-type` for `JSON` or `XML`, then uses `Form` (`form-data`).
748 749
	// See more at https://github.com/gin-gonic/gin/blob/master/binding/binding.go#L48
	if c.ShouldBind(&person) == nil {
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		log.Println(person.Name)
		log.Println(person.Address)
752
		log.Println(person.Birthday)
753 754 755 756 757 758
	}

	c.String(200, "Success")
}
```

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Test it with:
```sh
$ curl -X GET "localhost:8085/testing?name=appleboy&address=xyz&birthday=1992-03-15"
```

### Bind HTML checkboxes

See the [detail information](https://github.com/gin-gonic/gin/issues/129#issuecomment-124260092)

main.go

```go
...

type myForm struct {
    Colors []string `form:"colors[]"`
}

...

func formHandler(c *gin.Context) {
    var fakeForm myForm
    c.ShouldBind(&fakeForm)
    c.JSON(200, gin.H{"color": fakeForm.Colors})
}

...

```

form.html

```html
<form action="/" method="POST">
    <p>Check some colors</p>
    <label for="red">Red</label>
    <input type="checkbox" name="colors[]" value="red" id="red" />
    <label for="green">Green</label>
    <input type="checkbox" name="colors[]" value="green" id="green" />
    <label for="blue">Blue</label>
    <input type="checkbox" name="colors[]" value="blue" id="blue" />
    <input type="submit" />
</form>
```

result:

```
{"color":["red","green","blue"]}
```

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### Multipart/Urlencoded binding

```go
package main

import (
	"github.com/gin-gonic/gin"
)

type LoginForm struct {
	User     string `form:"user" binding:"required"`
	Password string `form:"password" binding:"required"`
}

func main() {
	router := gin.Default()
	router.POST("/login", func(c *gin.Context) {
		// you can bind multipart form with explicit binding declaration:
828 829
		// c.ShouldBindWith(&form, binding.Form)
		// or you can simply use autobinding with ShouldBind method:
830 831
		var form LoginForm
		// in this case proper binding will be automatically selected
832
		if c.ShouldBind(&form) == nil {
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			if form.User == "user" && form.Password == "password" {
				c.JSON(200, gin.H{"status": "you are logged in"})
			} else {
				c.JSON(401, gin.H{"status": "unauthorized"})
			}
		}
	})
	router.Run(":8080")
}
```

Test it with:
```sh
$ curl -v --form user=user --form password=password http://localhost:8080/login
```

### XML, JSON and YAML rendering

```go
func main() {
	r := gin.Default()

	// gin.H is a shortcut for map[string]interface{}
	r.GET("/someJSON", func(c *gin.Context) {
		c.JSON(http.StatusOK, gin.H{"message": "hey", "status": http.StatusOK})
	})

	r.GET("/moreJSON", func(c *gin.Context) {
		// You also can use a struct
		var msg struct {
			Name    string `json:"user"`
			Message string
			Number  int
		}
		msg.Name = "Lena"
		msg.Message = "hey"
		msg.Number = 123
		// Note that msg.Name becomes "user" in the JSON
		// Will output  :   {"user": "Lena", "Message": "hey", "Number": 123}
		c.JSON(http.StatusOK, msg)
	})

	r.GET("/someXML", func(c *gin.Context) {
		c.XML(http.StatusOK, gin.H{"message": "hey", "status": http.StatusOK})
	})

	r.GET("/someYAML", func(c *gin.Context) {
		c.YAML(http.StatusOK, gin.H{"message": "hey", "status": http.StatusOK})
	})

	// Listen and serve on 0.0.0.0:8080
	r.Run(":8080")
}
```

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#### SecureJSON

Using SecureJSON to prevent json hijacking. Default prepends `"while(1),"` to response body if the given struct is array values.

```go
func main() {
	r := gin.Default()

	// You can also use your own secure json prefix
	// r.SecureJsonPrefix(")]}',\n")

	r.GET("/someJSON", func(c *gin.Context) {
		names := []string{"lena", "austin", "foo"}

		// Will output  :   while(1);["lena","austin","foo"]
		c.SecureJSON(http.StatusOK, names)
	})

	// Listen and serve on 0.0.0.0:8080
	r.Run(":8080")
}
```
#### JSONP

Using JSONP to request data from a server  in a different domain. Add callback to response body if the query parameter callback exists.

```go
func main() {
	r := gin.Default()

	r.GET("/JSONP?callback=x", func(c *gin.Context) {
		data := map[string]interface{}{
			"foo": "bar",
		}
		
		//callback is x
		// Will output  :   x({\"foo\":\"bar\"})
		c.JSONP(http.StatusOK, data)
	})

	// Listen and serve on 0.0.0.0:8080
	r.Run(":8080")
}
```

#### AsciiJSON

Using AsciiJSON to Generates ASCII-only JSON with escaped non-ASCII chracters.

```go
func main() {
	r := gin.Default()

	r.GET("/someJSON", func(c *gin.Context) {
		data := map[string]interface{}{
			"lang": "GO语言",
			"tag":  "<br>",
		}

		// will output : {"lang":"GO\u8bed\u8a00","tag":"\u003cbr\u003e"}
		c.AsciiJSON(http.StatusOK, data)
	})

	// Listen and serve on 0.0.0.0:8080
	r.Run(":8080")
}
```

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### Serving static files

```go
func main() {
	router := gin.Default()
	router.Static("/assets", "./assets")
	router.StaticFS("/more_static", http.Dir("my_file_system"))
	router.StaticFile("/favicon.ico", "./resources/favicon.ico")

	// Listen and serve on 0.0.0.0:8080
	router.Run(":8080")
}
```

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### Serving data from reader

```go
func main() {
	router := gin.Default()
	router.GET("/someDataFromReader", func(c *gin.Context) {
		response, err := http.Get("https://raw.githubusercontent.com/gin-gonic/logo/master/color.png")
		if err != nil || response.StatusCode != http.StatusOK {
			c.Status(http.StatusServiceUnavailable)
			return
		}

		reader := response.Body
		contentLength := response.ContentLength
		contentType := response.Header.Get("Content-Type")

		extraHeaders := map[string]string{
			"Content-Disposition": `attachment; filename="gopher.png"`,
		}

		c.DataFromReader(http.StatusOK, contentLength, contentType, reader, extraHeaders)
	})
	router.Run(":8080")
}
```

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### HTML rendering

Using LoadHTMLGlob() or LoadHTMLFiles()

```go
func main() {
	router := gin.Default()
	router.LoadHTMLGlob("templates/*")
	//router.LoadHTMLFiles("templates/template1.html", "templates/template2.html")
	router.GET("/index", func(c *gin.Context) {
		c.HTML(http.StatusOK, "index.tmpl", gin.H{
			"title": "Main website",
		})
	})
	router.Run(":8080")
}
```

templates/index.tmpl

```html
<html>
	<h1>
		{{ .title }}
	</h1>
</html>
```

Using templates with same name in different directories

```go
func main() {
	router := gin.Default()
	router.LoadHTMLGlob("templates/**/*")
	router.GET("/posts/index", func(c *gin.Context) {
		c.HTML(http.StatusOK, "posts/index.tmpl", gin.H{
			"title": "Posts",
		})
	})
	router.GET("/users/index", func(c *gin.Context) {
		c.HTML(http.StatusOK, "users/index.tmpl", gin.H{
			"title": "Users",
		})
	})
	router.Run(":8080")
}
```

templates/posts/index.tmpl

```html
{{ define "posts/index.tmpl" }}
<html><h1>
	{{ .title }}
</h1>
<p>Using posts/index.tmpl</p>
</html>
{{ end }}
```

templates/users/index.tmpl

```html
{{ define "users/index.tmpl" }}
<html><h1>
	{{ .title }}
</h1>
<p>Using users/index.tmpl</p>
</html>
{{ end }}
```

1068 1069
#### Custom Template renderer

1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082
You can also use your own html template render

```go
import "html/template"

func main() {
	router := gin.Default()
	html := template.Must(template.ParseFiles("file1", "file2"))
	router.SetHTMLTemplate(html)
	router.Run(":8080")
}
```

1083 1084
#### Custom Delimiters

1085 1086 1087 1088 1089 1090
You may use custom delims

```go
	r := gin.Default()
	r.Delims("{[{", "}]}")
	r.LoadHTMLGlob("/path/to/templates"))
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```

#### Custom Template Funcs
1094

1095
See the detail [example code](examples/template).
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main.go

```go
1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130
import (
    "fmt"
    "html/template"
    "net/http"
    "time"

    "github.com/gin-gonic/gin"
)

func formatAsDate(t time.Time) string {
    year, month, day := t.Date()
    return fmt.Sprintf("%d%02d/%02d", year, month, day)
}

func main() {
    router := gin.Default()
    router.Delims("{[{", "}]}")
    router.SetFuncMap(template.FuncMap{
        "formatAsDate": formatAsDate,
    })
    router.LoadHTMLFiles("./testdata/template/raw.tmpl")

    router.GET("/raw", func(c *gin.Context) {
        c.HTML(http.StatusOK, "raw.tmpl", map[string]interface{}{
            "now": time.Date(2017, 07, 01, 0, 0, 0, 0, time.UTC),
        })
    })

    router.Run(":8080")
}

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```

raw.tmpl

```html
Date: {[{.now | formatAsDate}]}
```

Result:
```
Date: 2017/07/01
```

### Multitemplate

Gin allow by default use only one html.Template. Check [a multitemplate render](https://github.com/gin-contrib/multitemplate) for using features like go 1.6 `block template`.

### Redirects

1150
Issuing a HTTP redirect is easy. Both internal and external locations are supported.
1151 1152 1153 1154 1155 1156

```go
r.GET("/test", func(c *gin.Context) {
	c.Redirect(http.StatusMovedPermanently, "http://www.google.com/")
})
```
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Issuing a Router redirect, use `HandleContext` like below.

``` go
r.GET("/test", func(c *gin.Context) {
    c.Request.URL.Path = "/test2"
    r.HandleContext(c)
})
r.GET("/test2", func(c *gin.Context) {
    c.JSON(200, gin.H{"hello": "world"})
})
```
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### Custom Middleware

```go
func Logger() gin.HandlerFunc {
	return func(c *gin.Context) {
		t := time.Now()

		// Set example variable
		c.Set("example", "12345")

		// before request

		c.Next()

		// after request
		latency := time.Since(t)
		log.Print(latency)

		// access the status we are sending
		status := c.Writer.Status()
		log.Println(status)
	}
}

func main() {
	r := gin.New()
	r.Use(Logger())

	r.GET("/test", func(c *gin.Context) {
		example := c.MustGet("example").(string)

		// it would print: "12345"
		log.Println(example)
	})

	// Listen and serve on 0.0.0.0:8080
	r.Run(":8080")
}
```

### Using BasicAuth() middleware

```go
// simulate some private data
var secrets = gin.H{
	"foo":    gin.H{"email": "foo@bar.com", "phone": "123433"},
	"austin": gin.H{"email": "austin@example.com", "phone": "666"},
	"lena":   gin.H{"email": "lena@guapa.com", "phone": "523443"},
}

func main() {
	r := gin.Default()

	// Group using gin.BasicAuth() middleware
	// gin.Accounts is a shortcut for map[string]string
	authorized := r.Group("/admin", gin.BasicAuth(gin.Accounts{
		"foo":    "bar",
		"austin": "1234",
		"lena":   "hello2",
		"manu":   "4321",
	}))

	// /admin/secrets endpoint
	// hit "localhost:8080/admin/secrets
	authorized.GET("/secrets", func(c *gin.Context) {
		// get user, it was set by the BasicAuth middleware
		user := c.MustGet(gin.AuthUserKey).(string)
		if secret, ok := secrets[user]; ok {
			c.JSON(http.StatusOK, gin.H{"user": user, "secret": secret})
		} else {
			c.JSON(http.StatusOK, gin.H{"user": user, "secret": "NO SECRET :("})
		}
	})

	// Listen and serve on 0.0.0.0:8080
	r.Run(":8080")
}
```

### Goroutines inside a middleware

1253
When starting new Goroutines inside a middleware or handler, you **SHOULD NOT** use the original context inside it, you have to use a read-only copy.
1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314

```go
func main() {
	r := gin.Default()

	r.GET("/long_async", func(c *gin.Context) {
		// create copy to be used inside the goroutine
		cCp := c.Copy()
		go func() {
			// simulate a long task with time.Sleep(). 5 seconds
			time.Sleep(5 * time.Second)

			// note that you are using the copied context "cCp", IMPORTANT
			log.Println("Done! in path " + cCp.Request.URL.Path)
		}()
	})

	r.GET("/long_sync", func(c *gin.Context) {
		// simulate a long task with time.Sleep(). 5 seconds
		time.Sleep(5 * time.Second)

		// since we are NOT using a goroutine, we do not have to copy the context
		log.Println("Done! in path " + c.Request.URL.Path)
	})

	// Listen and serve on 0.0.0.0:8080
	r.Run(":8080")
}
```

### Custom HTTP configuration

Use `http.ListenAndServe()` directly, like this:

```go
func main() {
	router := gin.Default()
	http.ListenAndServe(":8080", router)
}
```
or

```go
func main() {
	router := gin.Default()

	s := &http.Server{
		Addr:           ":8080",
		Handler:        router,
		ReadTimeout:    10 * time.Second,
		WriteTimeout:   10 * time.Second,
		MaxHeaderBytes: 1 << 20,
	}
	s.ListenAndServe()
}
```

### Support Let's Encrypt

example for 1-line LetsEncrypt HTTPS servers.

1315
[embedmd]:# (examples/auto-tls/example1/main.go go)
1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339
```go
package main

import (
	"log"

	"github.com/gin-gonic/autotls"
	"github.com/gin-gonic/gin"
)

func main() {
	r := gin.Default()

	// Ping handler
	r.GET("/ping", func(c *gin.Context) {
		c.String(200, "pong")
	})

	log.Fatal(autotls.Run(r, "example1.com", "example2.com"))
}
```

example for custom autocert manager.

1340
[embedmd]:# (examples/auto-tls/example2/main.go go)
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```go
package main

import (
	"log"

	"github.com/gin-gonic/autotls"
	"github.com/gin-gonic/gin"
	"golang.org/x/crypto/acme/autocert"
)

func main() {
	r := gin.Default()

	// Ping handler
	r.GET("/ping", func(c *gin.Context) {
		c.String(200, "pong")
	})

	m := autocert.Manager{
		Prompt:     autocert.AcceptTOS,
		HostPolicy: autocert.HostWhitelist("example1.com", "example2.com"),
		Cache:      autocert.DirCache("/var/www/.cache"),
	}

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	log.Fatal(autotls.RunWithManager(r, &m))
}
```

### Run multiple service using Gin

See the [question](https://github.com/gin-gonic/gin/issues/346) and try the following example:

[embedmd]:# (examples/multiple-service/main.go go)
```go
package main

import (
	"log"
	"net/http"
	"time"

	"github.com/gin-gonic/gin"
	"golang.org/x/sync/errgroup"
)

var (
	g errgroup.Group
)

func router01() http.Handler {
	e := gin.New()
	e.Use(gin.Recovery())
	e.GET("/", func(c *gin.Context) {
		c.JSON(
			http.StatusOK,
			gin.H{
				"code":  http.StatusOK,
				"error": "Welcome server 01",
			},
		)
	})

	return e
}

func router02() http.Handler {
	e := gin.New()
	e.Use(gin.Recovery())
	e.GET("/", func(c *gin.Context) {
		c.JSON(
			http.StatusOK,
			gin.H{
				"code":  http.StatusOK,
				"error": "Welcome server 02",
			},
		)
	})

	return e
}

func main() {
	server01 := &http.Server{
		Addr:         ":8080",
		Handler:      router01(),
		ReadTimeout:  5 * time.Second,
		WriteTimeout: 10 * time.Second,
	}

	server02 := &http.Server{
		Addr:         ":8081",
		Handler:      router02(),
		ReadTimeout:  5 * time.Second,
		WriteTimeout: 10 * time.Second,
	}

	g.Go(func() error {
		return server01.ListenAndServe()
	})

	g.Go(func() error {
		return server02.ListenAndServe()
	})

	if err := g.Wait(); err != nil {
		log.Fatal(err)
	}
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}
```

### Graceful restart or stop

Do you want to graceful restart or stop your web server?
There are some ways this can be done.

We can use [fvbock/endless](https://github.com/fvbock/endless) to replace the default `ListenAndServe`. Refer issue [#296](https://github.com/gin-gonic/gin/issues/296) for more details.

```go
router := gin.Default()
router.GET("/", handler)
// [...]
endless.ListenAndServe(":4242", router)
```

An alternative to endless:

* [manners](https://github.com/braintree/manners): A polite Go HTTP server that shuts down gracefully.
* [graceful](https://github.com/tylerb/graceful): Graceful is a Go package enabling graceful shutdown of an http.Handler server.
* [grace](https://github.com/facebookgo/grace): Graceful restart & zero downtime deploy for Go servers.

If you are using Go 1.8, you may not need to use this library! Consider using http.Server's built-in [Shutdown()](https://golang.org/pkg/net/http/#Server.Shutdown) method for graceful shutdowns. See the full [graceful-shutdown](./examples/graceful-shutdown) example with gin.

[embedmd]:# (examples/graceful-shutdown/graceful-shutdown/server.go go)
```go
// +build go1.8

package main

import (
	"context"
	"log"
	"net/http"
	"os"
	"os/signal"
	"time"

	"github.com/gin-gonic/gin"
)

func main() {
	router := gin.Default()
	router.GET("/", func(c *gin.Context) {
		time.Sleep(5 * time.Second)
		c.String(http.StatusOK, "Welcome Gin Server")
	})

	srv := &http.Server{
		Addr:    ":8080",
		Handler: router,
	}

	go func() {
		// service connections
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		if err := srv.ListenAndServe(); err != nil && err != http.ErrServerClosed {
			log.Fatalf("listen: %s\n", err)
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		}
	}()

	// Wait for interrupt signal to gracefully shutdown the server with
	// a timeout of 5 seconds.
	quit := make(chan os.Signal)
	signal.Notify(quit, os.Interrupt)
	<-quit
	log.Println("Shutdown Server ...")

	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
	defer cancel()
	if err := srv.Shutdown(ctx); err != nil {
		log.Fatal("Server Shutdown:", err)
	}
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	log.Println("Server exiting")
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}
```

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### Build a single binary with templates

You can build a server into a single binary containing templates by using [go-assets][].
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[go-assets]: https://github.com/jessevdk/go-assets

```go
func main() {
	r := gin.New()

	t, err := loadTemplate()
	if err != nil {
		panic(err)
	}
	r.SetHTMLTemplate(t)

	r.GET("/", func(c *gin.Context) {
		c.HTML(http.StatusOK, "/html/index.tmpl",nil)
	})
	r.Run(":8080")
}

// loadTemplate loads templates embedded by go-assets-builder
func loadTemplate() (*template.Template, error) {
	t := template.New("")
	for name, file := range Assets.Files {
		if file.IsDir() || !strings.HasSuffix(name, ".tmpl") {
			continue
		}
		h, err := ioutil.ReadAll(file)
		if err != nil {
			return nil, err
		}
		t, err = t.New(name).Parse(string(h))
		if err != nil {
			return nil, err
		}
	}
	return t, nil
}
```

See a complete example in the `examples/assets-in-binary` directory.

### Bind form-data request with custom struct

The follow example using custom struct:

```go
type StructA struct {
    FieldA string `form:"field_a"`
}

type StructB struct {
    NestedStruct StructA
    FieldB string `form:"field_b"`
}

type StructC struct {
    NestedStructPointer *StructA
    FieldC string `form:"field_c"`
}

type StructD struct {
    NestedAnonyStruct struct {
        FieldX string `form:"field_x"`
    }
    FieldD string `form:"field_d"`
}

func GetDataB(c *gin.Context) {
    var b StructB
    c.Bind(&b)
    c.JSON(200, gin.H{
        "a": b.NestedStruct,
        "b": b.FieldB,
    })
}

func GetDataC(c *gin.Context) {
    var b StructC
    c.Bind(&b)
    c.JSON(200, gin.H{
        "a": b.NestedStructPointer,
        "c": b.FieldC,
    })
}

func GetDataD(c *gin.Context) {
    var b StructD
    c.Bind(&b)
    c.JSON(200, gin.H{
        "x": b.NestedAnonyStruct,
        "d": b.FieldD,
    })
}

func main() {
    r := gin.Default()
    r.GET("/getb", GetDataB)
    r.GET("/getc", GetDataC)
    r.GET("/getd", GetDataD)

    r.Run()
}
```

Using the command `curl` command result:

```
$ curl "http://localhost:8080/getb?field_a=hello&field_b=world"
{"a":{"FieldA":"hello"},"b":"world"}
$ curl "http://localhost:8080/getc?field_a=hello&field_c=world"
{"a":{"FieldA":"hello"},"c":"world"}
$ curl "http://localhost:8080/getd?field_x=hello&field_d=world"
{"d":"world","x":{"FieldX":"hello"}}
```

**NOTE**: NOT support the follow style struct:

```go
type StructX struct {
    X struct {} `form:"name_x"` // HERE have form
}

type StructY struct {
    Y StructX `form:"name_y"` // HERE hava form
}

type StructZ struct {
    Z *StructZ `form:"name_z"` // HERE hava form
}
```

In a word, only support nested custom struct which have no `form` now.

### Try to bind body into different structs

The normal methods for binding request body consumes `c.Request.Body` and they
cannot be called multiple times.

```go
type formA struct {
  Foo string `json:"foo" xml:"foo" binding:"required"`
}

type formB struct {
  Bar string `json:"bar" xml:"bar" binding:"required"`
}

func SomeHandler(c *gin.Context) {
  objA := formA{}
  objB := formB{}
  // This c.ShouldBind consumes c.Request.Body and it cannot be reused.
  if errA := c.ShouldBind(&objA); errA == nil {
    c.String(http.StatusOK, `the body should be formA`)
  // Always an error is occurred by this because c.Request.Body is EOF now.
  } else if errB := c.ShouldBind(&objB); errB == nil {
    c.String(http.StatusOK, `the body should be formB`)
  } else {
    ...
  }
}
```

For this, you can use `c.ShouldBindBodyWith`.

```go
func SomeHandler(c *gin.Context) {
  objA := formA{}
  objB := formB{}
  // This reads c.Request.Body and stores the result into the context.
  if errA := c.ShouldBindBodyWith(&objA, binding.JSON); errA == nil {
    c.String(http.StatusOK, `the body should be formA`)
  // At this time, it reuses body stored in the context.
  } else if errB := c.ShouldBindBodyWith(&objB, binding.JSON); errB == nil {
    c.String(http.StatusOK, `the body should be formB JSON`)
  // And it can accepts other formats
  } else if errB2 := c.ShouldBindBodyWith(&objB, binding.XML); errB2 == nil {
    c.String(http.StatusOK, `the body should be formB XML`)
  } else {
    ...
  }
}
```

* `c.ShouldBindBodyWith` stores body into the context before binding. This has
a slight impact to performance, so you should not use this method if you are
enough to call binding at once.
* This feature is only needed for some formats -- `JSON`, `XML`, `MsgPack`,
`ProtoBuf`. For other formats, `Query`, `Form`, `FormPost`, `FormMultipart`,
can be called by `c.ShouldBind()` multiple times without any damage to
performance (See [#1341](https://github.com/gin-gonic/gin/pull/1341)).

### http2 server push

http.Pusher is supported only **go1.8+**. See the [golang blog](https://blog.golang.org/h2push) for detail information.

[embedmd]:# (examples/http-pusher/main.go go)
```go
package main

import (
	"html/template"
	"log"

	"github.com/gin-gonic/gin"
)

var html = template.Must(template.New("https").Parse(`
<html>
<head>
  <title>Https Test</title>
  <script src="/assets/app.js"></script>
</head>
<body>
  <h1 style="color:red;">Welcome, Ginner!</h1>
</body>
</html>
`))

func main() {
	r := gin.Default()
	r.Static("/assets", "./assets")
	r.SetHTMLTemplate(html)

	r.GET("/", func(c *gin.Context) {
		if pusher := c.Writer.Pusher(); pusher != nil {
			// use pusher.Push() to do server push
			if err := pusher.Push("/assets/app.js", nil); err != nil {
				log.Printf("Failed to push: %v", err)
			}
		}
		c.HTML(200, "https", gin.H{
			"status": "success",
		})
	})

	// Listen and Server in https://127.0.0.1:8080
	r.RunTLS(":8080", "./testdata/server.pem", "./testdata/server.key")
}
```

## Testing

The `net/http/httptest` package is preferable way for HTTP testing.

```go
package main

func setupRouter() *gin.Engine {
	r := gin.Default()
	r.GET("/ping", func(c *gin.Context) {
		c.String(200, "pong")
	})
	return r
}

func main() {
	r := setupRouter()
	r.Run(":8080")
}
```

Test for code example above:

```go
package main

import (
	"net/http"
	"net/http/httptest"
	"testing"

	"github.com/stretchr/testify/assert"
)

func TestPingRoute(t *testing.T) {
	router := setupRouter()

	w := httptest.NewRecorder()
	req, _ := http.NewRequest("GET", "/ping", nil)
	router.ServeHTTP(w, req)

	assert.Equal(t, 200, w.Code)
	assert.Equal(t, "pong", w.Body.String())
}
```
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## Users

Awesome project lists using [Gin](https://github.com/gin-gonic/gin) web framework.

* [drone](https://github.com/drone/drone): Drone is a Continuous Delivery platform built on Docker, written in Go
* [gorush](https://github.com/appleboy/gorush): A push notification server written in Go.