captcha-generator/src/index.js

Production image verification code by jpeglib

import fs from 'fs';
import path from 'path';
import hcaptha from '../build/Release/hcaptha.node';

const tmpPath = path.join(__dirname, "/tmp/");

!fs.existsSync(tmpPath) && fs.mkdirSync(tmpPath);

const defaultDictionary = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", /*"l",*/ "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z", "A", "B", "C", "D", "E", "F", "G", "H", /*"I",*/ "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z"];
const platform = process.platform;

export function generate(text = createPlaintext(), width = 240, height = 112, charOffset = 0, fontSize = 100) {
    if (typeof text === "object") {
        const {text:t,width:w,height:h,charOffset:c,fontSize :f} = text;
        [text, width, height, charOffset, fontSize] = [t, w, h, c, f];
    }

    const isJpeg = ~["linux"].indexOf(platform) ? 1 : 0;
    const tmpFilePath = path.join(tmpPath, `/${Math.random()}.${isJpeg ? "jpeg" : "bmp"}`);
    const defaultQuality = 60;
    charOffset = charOffset || width / text.length;

    hcaptha.create(text, tmpFilePath, text.length, width, height, charOffset, defaultQuality, isJpeg, fontSize);

    const buf = fs.readFileSync(tmpFilePath);
    fs.unlinkSync(tmpFilePath);

    return CImg(buf, text, isJpeg ? "jpeg" : "bmp");
}

export function createPlaintext(count = 5, dictionary = defaultDictionary) {
    if (isNaN(count) || !(dictionary instanceof Array) || dictionary.length === 0) {
        throw Error("Parameter error");
    }

    let i = 0, len = dictionary.length, textList = "";
    while (i++ < count) {
        textList += dictionary[parseInt(Math.random() * len) % len];
    }

    return textList;
}

function CImg(buf, text, type) {
    var obj = {};

    return Object.defineProperties(obj, {
        buffer: {
            get: function () {
                return buf;
            },
            enumerable: true,
            configurable: false
        },
        plaintext: {
            get: function () {
                return text;
            },
            enumerable: true,
            configurable: false
        },
        imageType: {
            get: function () {
                return `image/${type}`;
            },
            enumerable: true,
            configurable: false
        },
        base64: {
            get: function () {
                return `data:image/${type};base64,${buf.toString("base64")}`;
            },
            enumerable: true,
            configurable: false
        }

    })
}


//hrobj.create("abcde", __dirname + "/c/" + start + ".bmp", 5, 240, 112, 50, 50, 0, 110);