javascript - Meteor: upload image file using FileReader on client and Npm.require("fs") on server - Stack Over

admin管理员组

文章数量:1431720

I'm having some trouble trying to upload an image file to my public/ folder using a standard <input type="file"> element.

So i have this event:

      "change .logoBusinessBig-upload":function(event, template){

            var reader = new FileReader()

            reader.addEventListener("load", function(){

                Meteor.call("saveFile", reader.result)

            })

            reader.readAsArrayBuffer(event.currentTarget.files[0])

        }

When i do a console.log(reader.result) inside the eventListeners callback, i get an ArrayBuffer object.

In my server/server.js file i have this Meteor.method:

        saveFile:function(file){

            var fs = Npm.require("fs")

            fs.writeFile('message.jpg', file, function (err) {

                console.log("file saved")

            });

        }

However, the file doesn't get saved and the console never says "file saved". What am i doing wrong here?

I'm having some trouble trying to upload an image file to my public/ folder using a standard <input type="file"> element.

So i have this event:

      "change .logoBusinessBig-upload":function(event, template){

            var reader = new FileReader()

            reader.addEventListener("load", function(){

                Meteor.call("saveFile", reader.result)

            })

            reader.readAsArrayBuffer(event.currentTarget.files[0])

        }

When i do a console.log(reader.result) inside the eventListeners callback, i get an ArrayBuffer object.

In my server/server.js file i have this Meteor.method:

        saveFile:function(file){

            var fs = Npm.require("fs")

            fs.writeFile('message.jpg', file, function (err) {

                console.log("file saved")

            });

        }

However, the file doesn't get saved and the console never says "file saved". What am i doing wrong here?

• javascript
• node.js
• meteor
• filereader
• fs

Share Improve this question Follow asked Nov 11, 2014 at 15:20 keviniuskevinius 4,63877 gold badges5151 silver badges7979 bronze badges 1

• The console does say "file saved"... i was looking in my browser console and not my mac console.. – kevinius Commented Nov 11, 2014 at 16:40

Add a ment  | 

2 Answers 2

Sorted by: Reset to default 7

Try this

//client.js

'change .logoBusinessBig-upload': function(event, template) {

    var file = event.target.files[0]; //assuming you have only 1 file
    if (!file) return;

    var reader = new FileReader(); //create a reader according to HTML5 File API

    reader.onload = function(event){          
      var buffer = new Uint8Array(reader.result) // convert to binary
      Meteor.call('saveFile',buffer);
    }

    reader.readAsArrayBuffer(file); //read the file as arraybuffer
}

//server.js

'saveFile': function(buffer){
    var fs = Npm.require("fs");
    fs.writeFile('/location',new Buffer(buffer),function(error){...});

}

Explanation

You read the file as ArrayBuffer, but current DDP can't send it, so you 'convert' it to Uint8Array, then Meteor.call

On the server, then you have to convert it by calling new Buffer(buffer) to save it. The '/location' can't be in meteor folder as this will trigger a reload, maybe save it to some TmpDir

I think 'fs' is a native nodejs's module. Simply try to requiring it this way: var fs = require('fs')

本文标签：