NodeError [ERR_STREAM_WRITE_AFTER_END]：结束后写入，在文件 createWriteStream 中答案

【问题标题】：NodeError [ERR_STREAM_WRITE_AFTER_END]: write after end, in File createWriteStreamNodeError [ERR_STREAM_WRITE_AFTER_END]：结束后写入，在文件 createWriteStream 中
【发布时间】：2020-06-30 05:42:42
【问题描述】：

在每次请求时，我都会尝试解密加密图像，并根据该图像提供响应。我在第一次请求时启动了我的服务器，它解密文件并发送正确的响应，而在下一次请求时，它尝试解密，但不将任何数据存储到新文件中，最后抛出错误“ERR_STREAM_WRITE_AFTER_END”，我的服务器崩溃了。

我的解密函数是

let decrypt = Crypto.createDecipher('aes-256-ctr', 'random_string');
async function decryptFile(encryptedFileDetails) {
    try {
        // write you code here..
        let decryptPromise = new Promise(async (decryptResolve) => {
            let r = FS.createReadStream(source);
            let w = FS.createWriteStream(destination);
            // start pipe
            r.pipe(decrypt).pipe(w);
            w.on('finish', function () {
                console.log('Decrypted file written to disk!');
                decryptResolve();
            });
        });
        await decryptPromise;
    } catch (error) {
        return Promise.reject(error);
    }
}


The error message I am receiving is

NodeError [ERR_STREAM_WRITE_AFTER_END]: write after end
    at writeAfterEnd (_stream_writable.js:248:12)
    at Decipher.Writable.write (_stream_writable.js:296:5)
    at ReadStream.ondata (_stream_readable.js:708:20)
    at ReadStream.emit (events.js:198:13)
    at addChunk (_stream_readable.js:287:12)
    at readableAddChunk (_stream_readable.js:268:11)
    at ReadStream.Readable.push (_stream_readable.js:223:10)
    at lazyFs.read (internal/fs/streams.js:181:12)
    at FSReqWrap.wrapper [as oncomplete] (fs.js:467:17) Emitted 'error' event at:
    at errorOrDestroy (internal/streams/destroy.js:107:12)
    at Decipher.onerror (_stream_readable.js:732:7)
    at Decipher.emit (events.js:198:13)
    at errorOrDestroy (internal/streams/destroy.js:107:12)
    at writeAfterEnd (_stream_writable.js:250:3)
    at Decipher.Writable.write (_stream_writable.js:296:5)
    [... lines matching original stack trace ...]
    at FSReqWrap.wrapper [as oncomplete] (fs.js:467:17)
</pre>

【问题讨论】：

decrypt 函数是什么？它来自某个模块吗？我们可以查看文档以了解它应该如何使用吗？
let decrypt = Crypto.createDecipher('aes-256-ctr', 'random_string'); 一个加密解密函数

标签： node.js fs cryptojs

【解决方案1】：

找到了解决办法。

我试图通过全局声明它来多次使用相同的密码流对象。但是一个密码流可以使用一次，下一次我们必须创建另一个对象。

async function decryptFile(encryptedFileDetails) {
    try {
        // write you code here..
        let decryptPromise = new Promise(async (decryptResolve) => {
            let decrypt = Crypto.createDecipher('aes-256-ctr', 'random_string');
            let r = FS.createReadStream(source);
            let w = FS.createWriteStream(destination);
            // start pipe
            r.pipe(decrypt).pipe(w);
            w.on('finish', function () {
                console.log('Decrypted file written to disk!');
                decryptResolve();
            });
        });
        await decryptPromise;
    } catch (error) {
        return Promise.reject(error);
    }
}

【讨论】：