https://github.com/mojocn/base64captcha

captcha of base64 image string
https://github.com/mojocn/base64captcha

anti-spam arithmetic-captcha audio-captchas base64 captcha captcha-generator go golang image-captcha yanzhengma

Last synced: 24 days ago
JSON representation

captcha of base64 image string

• Host: GitHub
• URL: https://github.com/mojocn/base64captcha
• Owner: mojocn
• License: other
• Created: 2017-12-12T12:17:07.000Z (almost 7 years ago)
• Default Branch: master
• Last Pushed: 2024-06-26T19:36:51.000Z (4 months ago)
• Last Synced: 2024-10-14T13:22:42.617Z (24 days ago)
• Topics: anti-spam, arithmetic-captcha, audio-captchas, base64, captcha, captcha-generator, go, golang, image-captcha, yanzhengma
• Language: Go
• Homepage: https://captcha.mojotv.cn/.netlify/functions/captcha
• Size: 10.5 MB
• Stars: 2,116
• Watchers: 51
• Forks: 269
• Open Issues: 9
• Metadata Files:
  • Readme: README.md
  • Funding: .github/FUNDING.yml
  • License: LICENSE
  • Code of conduct: CODE_OF_CONDUCT.md

Awesome Lists containing this project

README

        
# A flexible and various captcha package

![Test](https://github.com/mojocn/base64Captcha/workflows/Test/badge.svg)

[![Go Report Card](https://goreportcard.com/badge/github.com/mojocn/base64Captcha)](https://goreportcard.com/report/github.com/mojocn/base64Captcha)

[![GoDoc](https://godoc.org/github.com/mojocn/base64Captcha?status.svg)](https://godoc.org/github.com/mojocn/base64Captcha)

[![Build Status](https://travis-ci.org/mojocn/base64Captcha.svg?branch=master)](https://travis-ci.org/mojocn/base64Captcha)

[![codecov](https://codecov.io/gh/mojocn/base64Captcha/branch/master/graph/badge.svg)](https://codecov.io/gh/mojocn/base64Captcha)

![stability-stable](https://img.shields.io/badge/stability-stable-brightgreen.svg)

[![Foundation](https://img.shields.io/badge/Golang-Foundation-green.svg)](http://golangfoundation.org)

Base64captcha supports any unicode character and can easily be customized to support Math Chinese Korean Japanese Russian Arabic etc.

## 1. 📖📖📖 Doc & Demo

* [English](https://godoc.org/github.com/mojocn/base64Captcha)

* [中文文档](https://mojotv.cn/go/refactor-base64-captcha)

* [Playground](https://captcha.mojotv.cn)

## 2. 🚀🚀🚀 Quick start

### 2.1 🎬🎬🎬 Use history version

[Tag v1.2.2](https://github.com/mojocn/base64Captcha/tree/v1.2.2)

` go get github.com/mojocn/[email protected]`

or edit your `go.mod` file to

`github.com/mojocn/[email protected]`

### 2.2 📥📥📥 Download package

    go get -u github.com/mojocn/base64Captcha

For Gopher from mainland China without VPN `go get golang.org/x/image` failure solution:

- go version > 1.11

- set env `GOPROXY=https://goproxy.io`

### 2.3 🏂🏂🏂 How to code with base64Captcha

#### 2.3.1 🏇🏇🏇 Implement [Store interface](interface_store.go) or use build-in memory store

- [Build-in Memory Store](store_memory.go)

```go

type Store interface {

	// Set sets the digits for the captcha id.

	Set(id string, value string)

	// Get returns stored digits for the captcha id. Clear indicates

	// whether the captcha must be deleted from the store.

	Get(id string, clear bool) string

	

    //Verify captcha's answer directly

	Verify(id, answer string, clear bool) bool

}

```

#### 2.3.2 🏄🏄🏄 Implement [Driver interface](interface_driver.go) or use one of build-in drivers

There are some build-in drivers:

1. [Build-in Driver Digit](driver_digit.go)  

2. [Build-in Driver String](driver_string.go)

3. [Build-in Driver Math](driver_math.go)

4. [Build-in Driver Chinese](driver_chinese.go)

```go

// Driver captcha interface for captcha engine to to write staff

type Driver interface {

	//DrawCaptcha draws binary item

	DrawCaptcha(content string) (item Item, err error)

	//GenerateIdQuestionAnswer creates rand id, content and answer

	GenerateIdQuestionAnswer() (id, q, a string)

}

```

#### 2.3.3 🚴🚴🚴 ‍Core code [captcha.go](captcha.go)

`captcha.go` is the entry of base64Captcha which is quite simple.

```go

package base64Captcha

import (

	"math/rand"

	"time"

)

func init() {

	//init rand seed

	rand.Seed(time.Now().UnixNano())

}

// Captcha captcha basic information.

type Captcha struct {

	Driver Driver

	Store  Store

}

//NewCaptcha creates a captcha instance from driver and store

func NewCaptcha(driver Driver, store Store) *Captcha {

	return &Captcha{Driver: driver, Store: store}

}

//Generate generates a random id, base64 image string or an error if any

func (c *Captcha) Generate() (id, b64s string, err error) {

	id,content, answer := c.Driver.GenerateIdQuestionAnswer()

	item, err := c.Driver.DrawCaptcha(content)

	if err != nil {

		return "", "", err

	}

	c.Store.Set(id, answer)

	b64s = item.EncodeB64string()

	return

}

//Verify by a given id key and remove the captcha value in store,

//return boolean value.

//if you has multiple captcha instances which share a same store.

//You may want to call `store.Verify` method instead.

func (c *Captcha) Verify(id, answer string, clear bool) (match bool) {

	match = c.Store.Get(id, clear) == answer

	return

}

```

#### 2.3.4 🚵🚵🚵 ‍Generate Base64(image/audio) string

```go

func (c *Captcha) Generate() (id, b64s string, err error) {

	id,content, answer := c.Driver.GenerateIdQuestionAnswer()

	item, err := c.Driver.DrawCaptcha(content)

	if err != nil {

		return "", "", err

	}

	c.Store.Set(id, answer)

	b64s = item.EncodeB64string()

	return

}

```

#### 2.3.5 🤸🤸🤸 Verify Answer

```go

//if you has multiple captcha instances which shares a same store. You may want to use `store.Verify` method instead.

//Verify by given id key and remove the captcha value in store, return boolean value.

func (c *Captcha) Verify(id, answer string, clear bool) (match bool) {

	match = c.Store.Get(id, clear) == answer

	return

}

```

#### 2.3.6 🏃🏃🏃 ‍Full Example

```go

// example of HTTP server that uses the captcha package.

package main

import (

	"encoding/json"

	"fmt"

	"github.com/mojocn/base64Captcha"

	"log"

	"net/http"

)

//configJsonBody json request body.

type configJsonBody struct {

	Id            string

	CaptchaType   string

	VerifyValue   string

	DriverAudio   *base64Captcha.DriverAudio

	DriverString  *base64Captcha.DriverString

	DriverChinese *base64Captcha.DriverChinese

	DriverMath    *base64Captcha.DriverMath

	DriverDigit   *base64Captcha.DriverDigit

}

var store = base64Captcha.DefaultMemStore

// base64Captcha create http handler

func generateCaptchaHandler(w http.ResponseWriter, r *http.Request) {

	//parse request parameters

	decoder := json.NewDecoder(r.Body)

	var param configJsonBody

	err := decoder.Decode(&param)

	if err != nil {

		log.Println(err)

	}

	defer r.Body.Close()

	var driver base64Captcha.Driver

	//create base64 encoding captcha

	switch param.CaptchaType {

	case "audio":

		driver = param.DriverAudio

	case "string":

		driver = param.DriverString.ConvertFonts()

	case "math":

		driver = param.DriverMath.ConvertFonts()

	case "chinese":

		driver = param.DriverChinese.ConvertFonts()

	default:

		driver = param.DriverDigit

	}

	c := base64Captcha.NewCaptcha(driver, store)

	id, b64s, err := c.Generate()

	body := map[string]interface{}{"code": 1, "data": b64s, "captchaId": id, "msg": "success"}

	if err != nil {

		body = map[string]interface{}{"code": 0, "msg": err.Error()}

	}

	w.Header().Set("Content-Type", "application/json; charset=utf-8")

	json.NewEncoder(w).Encode(body)

}

// base64Captcha verify http handler

func captchaVerifyHandle(w http.ResponseWriter, r *http.Request) {

	//parse request json body

	decoder := json.NewDecoder(r.Body)

	var param configJsonBody

	err := decoder.Decode(&param)

	if err != nil {

		log.Println(err)

	}

	defer r.Body.Close()

	//verify the captcha

	body := map[string]interface{}{"code": 0, "msg": "failed"}

	if store.Verify(param.Id, param.VerifyValue, true) {

		body = map[string]interface{}{"code": 1, "msg": "ok"}

	}

	//set json response

	w.Header().Set("Content-Type", "application/json; charset=utf-8")

	json.NewEncoder(w).Encode(body)

}

//start a net/http server

func main() {

	//serve Vuejs+ElementUI+Axios Web Application

	http.Handle("/", http.FileServer(http.Dir("./static")))

	//api for create captcha

	http.HandleFunc("/api/getCaptcha", generateCaptchaHandler)

	//api for verify captcha

	http.HandleFunc("/api/verifyCaptcha", captchaVerifyHandle)

	fmt.Println("Server is at :8777")

	if err := http.ListenAndServe(":8777", nil); err != nil {

		log.Fatal(err)

	}

}

```

#### 2.3.7 Example Use Etcd as store

[captcha with etcd database as store](captcha_with_etcd_exmaple.md)

## 3. 🎨🎨🎨 Customization

You can customize your captcha display image by implementing [interface driver](interface_driver.go) 

and [interface item](interface_item.go).

There are some example for your reference.

1. [DriverMath](driver_math.go)

2. [DriverChinese](driver_chinese.go)

3. [ItemChar](item_char.go)

***You can even design the [captcha struct](captcha.go) to whatever you prefer.***

## 4. 💖💖💖 Thanks

- [dchest/captha](https://github.com/dchest/captcha)

- [@slayercat](https://github.com/slayercat)

- [@amzyang](https://github.com/amzyang)

- [@Luckyboys](https://github.com/Luckyboys)

- [@hi-sb](https://github.com/hi-sb)

## 5. 🍭🍭🍭 Licence

base64Captcha source code is licensed under the Apache Licence, Version 2.0

(http://www.apache.org/licenses/LICENSE-2.0.html).