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js图片流文件加解密

js图片流文件加解密

作者: SA_Arthur | 来源:发表于2024-07-22 17:09 被阅读0次
const newFile = await encipherFileList(file);
import CryptoJS from 'crypto-js';
import CryptoU8array from "./crypto-en";
import hooks from '/@/hooks'

const key = CryptoJS.enc.Utf8.parse("1111111111111111"); // 十六位十六进制数作为秘钥
const iv = CryptoJS.enc.Utf8.parse('1111111111111111'); // 十六位十六进制数作为秘钥偏移量

/**
 * 使用 AES 进行文件加密
 * @param word 需要加密的二进制流文件 
 * @returns 返回base64
 */
export function encryptFile(word) {
    const messageWordArray = CryptoU8array.u8array.parse(word);
    const encrypted = CryptoJS.AES.encrypt(messageWordArray, key, {
        iv: iv,
        mode: CryptoJS.mode.CBC,
        padding: CryptoJS.pad.Pkcs7
    });
    const encryptedBytes = encrypted.ciphertext;
    return CryptoU8array.u8array.stringify(encryptedBytes);
}

/**
 * 转换blob对象
 */
export function atobToblob(intArray,type) {
  // 创建一个 Blob 对象
  var blob = new Blob([intArray], { type: type });
  return blob;
}

/**
 * 使用 AES 进行文件解密
 * @param word 需要解密的二进制流文件 
 * @returns 返回base64
 */
export function decryptFile(word) {
    const messageWordArray = CryptoU8array.u8array.parse(word);
    const decrypt = CryptoJS.AES.decrypt({ ciphertext: messageWordArray }, key, {
        iv: iv,
        mode: CryptoJS.mode.CBC,
        padding: CryptoJS.pad.Pkcs7
    });
    return CryptoU8array.u8array.stringify(decrypt);
}

export function arrayBufferToBlob(arrayBuffer, type) {
    return new Blob([new Uint8Array(arrayBuffer)], { type });
}

/**
 * 加密文件
 * @param file 
 * @returns 
 */
export function encipherFileList(file) {
    return new Promise((resolve, reject) => {
        try {
            let reader = new FileReader()
            reader.readAsArrayBuffer(file) // 以二进制数据读取文件
            reader.onload = async () => {
              let fileContent =  new Uint8Array(reader.result) // 转成Uint8Array类型
              let encryptedContent = encryptFile(fileContent); // 加密
              let blobType = file.type
              let fileName = file.name
              let blob = atobToblob(encryptedContent, blobType) // 将加密后串转blob
              let blobToFile = new File([blob], fileName, {
                type: blobType,  
                lastModified: Date.now()  
              }); // 得到加密文件
              resolve(blobToFile)
            }
        } catch {
            reject()
            console.log('err: encipherFileList')
        }

    })
}

/**
 * 获取流文件base64
 * @param file 
 * @returns 
 */
function getBase64(file: File) {
    return new Promise((resolve, reject) => {
      const reader = new FileReader();
      reader.readAsDataURL(file);
      reader.onload = () => {
        resolve(reader.result);
      }
      reader.onerror = (error) => reject(error);
    });
}

/**
 * 检测图片是否存在
 * @param url 图片文件地址
 * @returns 
 */
export function verifyImageComplete(url) {
    return new Promise((resolve, reject) => {
        var img = new Image();
        img.onload = function() {
            console.log('Image is valid and can be displayed.');
            resolve(true)
        };
        img.onerror = function() {
            console.log('Image is either corrupt or cannot be displayed.');
            resolve(false)
        };
        img.src = `${hooks.defaultAPI}${url}`;
    })
}

/**
 * 解密文件
 * @param file 
 * @returns 
 */
export function decryptFileList(file) {
    return new Promise(async (resolve, reject) => {
        try {
            const blob = await fetch(`${hooks.defaultAPI}${file.url}`).then(response => response.blob());
            const arrayBuffer = await new Response(blob).arrayBuffer();
            const encryptedContent = new Uint8Array(arrayBuffer);
            const decryptedContent = decryptFile(encryptedContent);
            const decryptedBlob = arrayBufferToBlob(decryptedContent, 'image/jpeg'); // 这里假设解密后是图片类型
            const decryptedFile = new File([decryptedBlob], file.name, { type: decryptedBlob.type });
            file.url = URL.createObjectURL(decryptedFile)
            const base64 = await getBase64(decryptedFile)
            resolve({ url: file.url, file: decryptedFile, base64 })
        } catch {
            console.log('err: decryptFileList')
            reject()
        }
    })
}

/**
 * 将图片转换成流文件
 * @param url 
 * @returns 
 */
export function urlTransFile(url) {
    return new Promise(async (resolve, reject) => {
        const blob = await fetch(`${hooks.defaultAPI}${url}`).then(response => response.blob());
        const file = new File([blob], "image.jpg", { type: "image/jpeg" });
        resolve(file)
    }) 
}

/**
 * 获取图片缩略图
 * @param imageFile 
 * @param maxWidth 
 * @param maxHeight 
 * @param quality 
 * @returns 
 */
export function generateThumbnail(imageFile, maxWidth, maxHeight, quality) {
    return new Promise((resolve, reject) => {
        const reader = new FileReader();
        reader.onload = () => {
            const img = new Image();
            img.onload = () => {
                const canvas = document.createElement('canvas');
                const ctx = canvas.getContext('2d');

                let width = img.width;
                let height = img.height;

                // 计算缩放比例
                if (width > height) {
                    if (width > maxWidth) {
                        height *= maxWidth / width;
                        width = maxWidth;
                    }
                } else {
                    if (height > maxHeight) {
                        width *= maxHeight / height;
                        height = maxHeight;
                    }
                }

                canvas.width = width;
                canvas.height = height;

                // 绘制图片到canvas
                ctx.drawImage(img, 0, 0, width, height);

                // 将canvas转换为base64格式的缩略图
                const thumbnailDataURL = canvas.toDataURL('image/jpeg', quality);

                resolve(thumbnailDataURL);
            };
            img.onerror = function() {
                resolve('err');
            };
            img.src = reader.result;
        };
        reader.onerror = (error) => reject(error);
        reader.readAsDataURL(imageFile);
    });
}

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