如何使用fs读取和保存base64图像

Question

I am creating an api node that on the front end (it is separate from the api, I am using fetch to send the data) I am selecting a jpg file and sending in base64 form to the api, I usually receive the base64 in the controller with "var imagem = req.body.imagem; ". I need now to take this base64 and turn it into an image to save in the ../../public/img directory. How could I do that?

const mongoose = require('mongoose');
const Cup = require('../models/Cup');
module.exports = {
    //listagem
    async index(req, res) {
        const cups = await Cup.find();

        return res.json(cups);
    },
    //criaçao
    async store(req, res) {
        var nome = req.body.nome;
        var caminho = req.body.caminho;
        var tema = req.body.tema;
        var imagem = req.body.imagem;
        const cup = await Cup.create({
            nome: nome,
            caminho: caminho,
            tema: tema
        });
        return res.json(cup);
    }
}

Answer 1

You can convert an image from a base64 representation to its binary representation by converting the string to a Buffer - new Buffer(b64_image, 'base64') (read more on this in this answer ). You can then save the buffer to the local filesystem using either fs.writeFile (in case you'd like to save the file asynchronously) or fs.writeFileSync (in case you'd like to save the file synchronously).

What you're trying to do could be accomplished with something like this:

const fs = require("fs");

const base64Image = "BASE_64_IMAGE";
const imageBuffer = new Buffer(base64Image, "base64");

fs.writeFileSync("image.png", imageBuffer);