Base64编码后将axios图像流转换为字符串？

Question

到目前为止，我有这个：const Fs = require('fs')  const Path = require('path')  const Axios = require('axios')var {Base64Encode} = require('base64-stream');const url = 'https://unsplash.com/photos/AaEQmoufHLk/download?force=true'const response = await Axios({      url,      method: 'GET',      responseType: 'stream'    })response.data.pipe(new Base64Encode())这个base 64 对图像进行编码。我们怎样才能把它变成一个字符串。我试过这样的事情：  function streamToString (stream) {    const chunks = []    return new Promise((resolve, reject) => {      stream.on('data', chunk => chunks.push(chunk))      stream.on('error', reject)      stream.on('end', () => resolve(Buffer.concat(chunks).toString('utf8')))    })  }const result = await streamToString(response.data.pipe(new Base64Encode()))但它错误。想法？

Answer 1

在您的示例中，您使用了Base64encode已经抽出字符串的模块 - 这使得上面的示例失败（除非那是因为顶级等待）。您实际上不需要将块转换为字符串，因为它们已经是字符串，因此可以进行简单的串联。

事实上，仅使用 node.js 流，整个事情可能会简单 10 倍：

const Axios = require('axios')

const {PassThrough} = require("stream");

const url = 'https://unsplash.com/photos/AaEQmoufHLk/download?force=true';

(async function() {

    const response = await Axios({

        url,

        method: 'GET',

        responseType: 'stream'

    });

    // we just pipe the data (the input carries it's own encoding)

    // to a PassThrough node stream that outputs `base64`.

    const chunks = response.data

        .pipe(new PassThrough({encoding:'base64'}));

    // then we use an async generator to read the chunks

    let str = '';

    for await (let chunk of chunks) {

        str += chunk;

    }

    // et voila! :)

    console.log(str);

})();