NodeJS缓冲区Base64文件限制

Question

Tried to upload an image using Base64 but if the string is long the bottom of the stored image is blank white.

upload.js

var uuid = require('node-uuid');
var fs = require('fs');

exports.uploadImage = function(base64Str, callback) {
    var filename = uuid.v1()+'.png';
    var bitmap = new Buffer(base64Str, 'base64');
    fs.writeFileSync(filename, bitmap);
    callback(filename);
};

server.js

var fs = require('fs');
var restify = require('restify');  
var server = restify.createServer();
server.use(restify.bodyParser());

var upload = require('./modules/upload');

server.post('/images', function(req, res) {
    upload.uploadImage(req.params.myImage, function(filename) {
        console.log('processing image');
        res.send(filename);
        res.end();
    });
});

server.listen(3000);

It works for a string of length 499016 bytes but not if the string is 847508 bytes. Is there a documented size limit and, if not, how can I upload and un-encode longer strings?

Answer 1

You might be hitting a request size limit. One alternative would be to upload your image as multipart/form-data . You can do this with the mapFiles options in restify.bodyParser , and you can test it by choosing file instead of text in your Postman form-data.

Edited: fs.rename might make more sense here for testing purposes. In a practical application you might want to save uploaded files elsewhere, on s3 perhaps.

var fs = require('fs');
var restify = require('restify');
var server = restify.createServer();
server.use(restify.bodyParser({
    mapFiles: true
}));

var uuid = require('node-uuid');
var fs = require('fs');

var uploadImage = function(path, callback) {
    var filename = uuid.v1() + '.png';
    fs.rename(path, filename, function(err) {
        if (err) {
            throw err;
        }
        callback(filename);
    });
};

server.post('/images', function(req, res) {
    uploadImage(req.files.myImage.path, function(filename) {
        res.send(filename);
        res.end();
    });
});

server.listen(3000);