Extra params don't seem to be sent

[JeroenRood]

So far, Delivery.js has amazed me when it comes to simplicity of sending files through Socket.io. Props for making such a module! :-)

When I use delivery.send(file,extraParams) (extraParams being an object, as described in the readme), and I check the content of file on the server after receive.succes, I don't see the property params (I used Object.keys() to retrieve all the keys from the file-object), and reading file.params returns undefined.

I'd like to send meta-data with my application. Do you have an idea how I can include this meta data (or params) after all? I tried altering Delivery.prototype.send, FilePackage and FilePackage.prototype.prepBatch; but with no avail so far. Could you give me a pointer for fixing this, or help me out here?

Thanks in advance for taking a look at it!

[JeroenRood]

I realized I forgot to post my code. This excerpt applies to this issue:

Client:

function process_files(e,delivery){
    var file = e.target.files[0];
    var b = document.body;
    if(b.getAttribute("data-album")){
        mrI = b.getAttribute('data-album');
    }
    else {
        mrI = -1;
    }

    delivery.send(file, {loc:b.getAttribute("data-lat")+"|"+b.getAttribute("data-long"),mI:mrI});
    e.preventDefault();
}
socket.on('connect',function(){
    var delivery = new Delivery(socket);

    delivery.on('delivery.connect',function(delivery){
        document.getElementById('photoInput').addEventListener("change", function(e) {
            process_files(e,delivery);
        });
        document.getElementById('audioInput').addEventListener("change", function(e) {
            process_files(e,delivery);
        });
        document.getElementById('videoInput').addEventListener("change", function(e) {
            process_files(e,delivery);
        });
    });

    delivery.on('send.success',function(fileUID){
      console.log("file was successfully sent.");
    });
});

Server:

delivery.on('receive.success',function(file){
        console.log("FILE: "+ JSON.stringify(Object.keys(file),null,2)); // no property "params" here
        // The code to fetch file.params was alternatively put over here, with no avail:
        /*
            var extraParams = file.params;
            console.log(JSON.stringify(extraParams,null,2));
            var mI = extraParams.mI;
        */
        fs.writeFile(__dirname + "/public/media/"+file.name,file.buffer, function(err){
            if(err){
                console.log('File could not be saved. '+ err);
            }
            else{
                var extraParams = file.params;
                console.log(JSON.stringify(extraParams,null,2)); // returns undefined
                var mI = extraParams.mI; // throws error, as property 'mI' of undefined can't be read
                files.push({
                    src:file.name,
                    loc:extraParams.loc,
                    time:(new Date()).getTime(),
                    mI: mI
                });
                console.log(JSON.stringify(files));
                sc = Object.keys(io.nsps["/"].adapter.rooms);
                console.log("rooms: "+JSON.stringify(sc,null,2));
                us = Object.keys(users);
                console.log("user IDs: "+JSON.stringify(us,null,2));
                data = fetchGroupData(sc,us);
                socket.emit('invite_channel','{"type":"welcomeBackUpdate","cList":' +data.cn +',"rID":' +data.cid +',"locs":' +data.locs +',"times":' +data.times+'}');
                console.log('File saved.');
            }
        });
    });

[JeroenRood]

I think I resolved the problem. Over at deliver.js (client), FilePackage.prototype.prepBatch is applied on _this, which is stored before actually adding this.params.

This code is what I am talking about:

function FilePackage(file,receiving,params){
      console.log("Params (received by FilePackage): "+JSON.stringify(params,null,2));

    this.name = file.name;
    this.size = file.size;
    _this = this;
    if(receiving){
      this.uid = file.uid;
      this.isText = file.isText;
      this.mimeType = file.mimeType;
      this.data = file.data;
      this.dataURLPrefix = file.prefix;
      this.params = file.params;

      pubSub.publish('receive.success',this);
    }else{
      //Sending a file.
      this.params = params;
        console.log("Params (this.params, filePackage): "+JSON.stringify(this.params,null,2));
      this.uid = this.getUID();
      this.reader = new FileReader();

      this.reader.onerror = function(obj){};

      this.reader.onload = function(){
        _this.base64Data = _this.reader.result;
        _this.prepBatch();
      };
      this.reader.readAsDataURL(file);
    };
  };

_this = this; should be placed after assigning this.params. As follows:

  function FilePackage(file,receiving,params){
      console.log("Params (received by FilePackage): "+JSON.stringify(params,null,2));

    this.name = file.name;
    this.size = file.size;
    // _this = this; --> assigned too early
    if(receiving){
      this.uid = file.uid;
      this.isText = file.isText;
      this.mimeType = file.mimeType;
      this.data = file.data;
      this.dataURLPrefix = file.prefix;
      this.params = file.params;
      _this = this; // includes all information from this
      pubSub.publish('receive.success',this);
    }else{
      //Sending a file.
      this.params = params;
        console.log("Params (this.params, filePackage): "+JSON.stringify(this.params,null,2));
      this.uid = this.getUID();
      this.reader = new FileReader();

      this.reader.onerror = function(obj){};

      this.reader.onload = function(){
        _this.base64Data = _this.reader.result;
        _this.prepBatch();
      };
      _this = this; // includes all information from this
      this.reader.readAsDataURL(file);
    };
  };

[liamks]

@JeroenRood _this is a reference to this, not a copy of it, so it should be fine where it is. Also _this isn't needed in the if receiving is true, just if we're sending. I also wrote this a few years ago, a better way to do the above would be:

 }else{
      //Sending a file.
      this.params = params;
        console.log("Params (this.params, filePackage): "+JSON.stringify(this.params,null,2));
      this.uid = this.getUID();
      this.reader = new FileReader();

      this.reader.onerror = function(obj){};

      this.reader.onload = function(){
        this.base64Data = this.reader.result;
        this.prepBatch();
      }.bind(this);

      this.reader.readAsDataURL(file);
    };

The code above is for the FilePackage object, I think you're looking at the file object. Different events return different object types. I haven't looked at this code in years unfortunately, so I can't offer too much more help. Have you thought about using something like jquery-file-upload? It works basically everywhere, but is more difficult to setup.

[WilixLead]

Please update npm package. This package have older code when github

Hi there,

Is there any workaround for this issue? I could not fix it with the above suggestions.

[WilixLead]

@piyusharora420 just copy delivery from github. In npm package stored old code I think.
I solved the problem by this way:

1. npm install delivery
2. replace files in node_modules/delivery/lib to lib from this github repository.

Now all works, in server side you can get params by this way:
var delivery = dl.listen(socket);
delivery.on('receive.success',function(file){
console.log('Extra Params', file.params);
});

in front-end you can use this:
delivery.send(file, {extraParam1: '123', extaraParam2: '456'});

Thanks a lot @WilixLead. It fixed the issue.