Golang Image Verification Code

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Why Base64 Pictures for RESTful services

  Data URIs 支持大部分浏览器,IE8之后也支持.  小图片使用base64响应对于RESTful服务来说更便捷

Godoc Documentation

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WAV file

Installing the Golang Package

go get -u github.com/mojocn/base64Captcha

For Chinese mainland Gopher go get golang.org/x/image failure Solution:

    mkdir -p $GOPATH/src/golang.org/x    cd $GOPATH/src/golang.org/x    git clone https://github.com/golang/image.git

Create an image verification code

Import "Github.com/mojocn/base64captcha" func democodecaptchacreate () {//config struct for digits//digital Verification code configuration VAR c ONFIGD = base64captcha.configdigit{height:80, width:240, maxskew:0.7, Dotcount        : Captchalen:5,}//config struct for audio//sound Verification code configuration var Configa = base64captcha.configaudio{ Captchalen:6, Language: "zh",}//config struct for Character//character, formula, CAPTCHA configuration var CONFIGC = base 64captcha.configcharacter{height:60, width:240,//const captchamodenumber        : Numbers, Captchamodealphabet: Letters, captchamodearithmetic: Arithmetic, Captchamodenumberalphabet: mixed digital letters.        Mode:base64Captcha.CaptchaModeNumber, ComplexOfNoiseText:base64Captcha.CaptchaComplexLower,         ComplexOfNoiseDot:base64Captcha.CaptchaComplexLower, Isshowhollowline:false, Isshownoisedot:false, Isshownoisetext:false, IsshowslimeLine:false, Isshowsineline:false, Captchalen:6,}//Create a sound verification code//generatecaptcha first    The parameter is an empty string, and the package automatically generates random UIID on the server with a random seed. Idkeya, CapA: = Base64captcha.generatecaptcha ("", Configa)//base64 encoded Base64stringa: = Base64captcha.captchawriteto    Base64encoding (CapA)//Create character formula verification code.    Generatecaptcha The first parameter is an empty string, the package automatically generates random UIID on the server with a random seed. IDKEYC, CapC: = Base64captcha.generatecaptcha ("", CONFIGC)//base64 encoded BASE64STRINGC: = Base64captcha.captchawriteto    Base64encoding (CapC)//Create a digital verification code.    Generatecaptcha The first parameter is an empty string, the package automatically generates random UIID on the server with a random seed. Idkeyd, CapD: = Base64captcha.generatecaptcha ("", ConfigD)//base64 encoded BASE64STRINGD: = Base64captcha.captchawriteto Base64encoding (CapD) fmt. Println (Idkeya, Base64stringa, "\ n") fmt. Println (IDKEYC, BASE64STRINGC, "\ n") fmt. Println (Idkeyd, Base64stringd, "\ n")}

Verifying the Image Verification code

import "github.com/mojocn/base64Captcha"func verfiyCaptcha(idkey,verifyValue string){    verifyResult := base64Captcha.VerifyCaptcha(idkey, verifyValue)    if verifyResult {        //success    } else {        //fail    }}

Using Golang to build API services

Example of HTTP server that uses the captcha package.package mainimport ("Encoding/json" "FMT" "github.com/mo              Jocn/base64captcha "" "Log" "Net/http")//configjsonbody JSON request Body.type configjsonbody struct {Id String Captchatype string Verifyvalue string Configaudio base64captcha.configaudio Configchara Cter base64captcha.configcharacter configdigit base64captcha.configdigit}//base64captcha create http Handlerfunc g Eneratecaptchahandler (w http. Responsewriter, R *http. Request) {//parse requests parameters//Receive client to send the requested parameter decoder: = JSON. Newdecoder (R.body) var postparameters configjsonbody err: = decoder. Decode (&postparameters) if err! = Nil {log.     PRINTLN (ERR)} defer r.body.close ()//create base64 encoding CAPTCHA//Create Base64 image verification code var config interface{}      Switch Postparameters.captchatype {case ' audio ': config = postparameters.configaudio case ' character ':  Config = postparameters.configcharacter default:config = postparameters.configdigit}//generatecaptcha    The first parameter is an empty string, and the package automatically generates random UIID on the server with a random seed. Captchaid, Digitcap: = Base64captcha.generatecaptcha (postparameters.id, config) base64png: = Base64captcha.captchawritetobase64encoding (DIGITCAP)//or You can does this//You may also be using the default parameters to generate an image verification code//base64png: = Cap Tcha. Generatecaptchapngbase64stringdefault (Captchaid)//set JSON response//Set JSON response W.header (). Set ("Content-type", "Application/json;    Charset=utf-8 ") Body: = map[string]interface{}{" code ": 1," Data ": Base64png," Captchaid ": Captchaid," MSG ":" Success "} Json. Newencoder (W). Encode (body)}//Base64captcha Verify HTTP handlerfunc captchaverifyhandle (w http. Responsewriter, R *http. Request) {//parse requests parameters//Receive client to send the requested parameter decoder: = JSON. Newdecoder (R.body) var postparameters configjsonbody err: = decoder. Decode (&postparameters) if err! = Nil {log.   PRINTLN (ERR) } defer R.body.close ()//verify the CAPTCHA//Compare Image Verification code Verifyresult: = Base64captcha.verifycaptcha (Postparamet ERs. Id, Postparameters.verifyvalue)//set JSON response//Set JSON response W.header (). Set ("Content-type", "Application/json; Charset=utf-8 ") Body: = map[string]interface{}{" code ":" Error "," Data ":" Validation Failed "," MSG ":" Captcha Failed "} if Verifyre Sult {BODY = map[string]interface{}{"code": "Success", "Data": "Authenticated via", "MSG": "Captcha Verified"}} JSON. Newencoder (W). Encode (body)}//start a net/http server//start Golang net/http server func main () {//serve Vuejs+elementui+axios Web Applicatio N http. Handle ("/", HTTP. Fileserver (http. Dir ("./static")))//api for Create CAPTCHA//Create Image Verification code API HTTP. Handlefunc ("/api/getcaptcha", Generatecaptchahandler)//api for verify Captcha http. Handlefunc ("/api/verifycaptcha", Captchaverifyhandle) fmt. Println ("Server is at localhost:3333") if err: = http. Listenandserve ("localhost:3333", nil);   Err! = Nil {     Log. Fatal (ERR)}}

Run Demo code

cd $GOPATH/src/github.com/mojocn/captcha/examplesgo run main.go