Follow standard convention for Arrays

[coolaj86]

According to common convention (i.e. php, python, ruby) named fields ending with square brackets [] should be treated as arrays.

This example HTTP POST should produce a parsed object like the one shown here below:

Shorter snippet from link above:

-----------------------------114772229410704779042051621609
Content-Disposition: form-data; name="attachments[]"; filename="file1.txt"
Content-Type: text/plain

This is file 1

-----------------------------114772229410704779042051621609
Content-Disposition: form-data; name="attachments[]"; filename="file2.txt"
Content-Type: text/plain

This is file 2
It has three lines
And was created on OS X

Parsed Object:

{
    name: "AJ ONeal",
    email: "coolaj86@email.com",
    // <Object HTML5::FileAPI::File>
    avatar: {
        name: "smiley-cool.png",
        size: 869,
        type: "image/png",
        path: "/tmp/ab489fe1d9a4df.png"
    },
    attachments: [
        // <Object HTML5::FileAPI::File>
        {
            name: "file1.txt",
            size: 15,
            type: "text/plain",
            path: "/tmp/c3e29fa4de1d9f.png"
        },
        {
            name: "file2.txt",
            size: 58,
            type: "text/plain",
            path: "/tmp/9a4ab48dffe1d9.png"
        }
    ]
}

[felixge]

I'm not sure if I want this to be part of formdiable yet. I can see how it's nice, but at the same time it feels like sugar that can easily build on top of formidable. Let me know why you think it's important.

[coolaj86]

Perhaps my understanding is incorrect (I'm using express, not formidable directly, so correct me if I'm mistaken), but formidable can't currently accept uploads from multiple input fields

So either using the common convention []

<input type="file" name="attachments[]" multiple=multiple>

Or not

<input type="file" name="attachments" multiple=multiple>

I can't get access to form.attachments[0]. Is this not a bug?

The HTML spec treats all form fields as Arrays. However, that's the same ugly way that xml does it.

I agree that we should not encourage that mistake -- especially since web frameworks have traditionally used the [] convention, and it works well, is simple to implement, and intuitive to understand.

Although it may not be the best solution, but it's what end-developers are accustomed to.

That said, I would be okay with any solution to the bug

• using the convention of [] to treat the object as an array - this works generally well and I support the web framework community in its use
• guessing at when an object should be an array - I don't like this because it is inconsistent.
• making everything an array whether it was intended to be or not - perhaps the best solution, certainly standards compliant, albeit somewhat ugly.

The issue is that when I use a multiple file input form, I should be able to get at all the files.

[tj]

yeah I dont personally care what the solution is but this is pretty important, [] was the first thing I tried

[felixge]

The issue is that when I use a multiple file input form, I should be able to get at all the files.

The API supports that. You just need to listen for the 'file' event. If express/connect does not expose that, a patch there might be the first thing to consider?

[tj]

connect-form is just a really thin layer around formidable, I think it is the final callback wit the field hash that ends up being "invalid" with multiples

[felixge]

connect-form is just a really thin layer around formidable, I think it is the final callback wit the field hash that ends up being "invalid" with multiples

The callback is meant as a simplified API which doesn't handle multiple fields with the same name. But I guess connect-form is not meant to "emit" individual file events anyway?

--fg

[coolaj86]

Here's a paired Client / Server upload test case:
https://github.com/coolaj86/node-file-api/blob/master/examples/upload-client.js
https://github.com/coolaj86/node-file-api/blob/master/examples/upload-server.js

And the reference HTTP POST:
https://github.com/coolaj86/node-file-api/raw/master/examples/upload-http-post.raw

[coolaj86]

So which of the two should change? Express or Formidable?

I would really appreciate formidable handling it appropriately since I won't always be using express when I handle uploads, but I would pretty much always like to use formidable when I handle uploads.

I think that the change will benefit more projects in general if it happens in the formidable layer.

[tj]

you can still use formidable directly.. connect-form is just a convenience middleware

This select tab with multiple fields problem is definitely a bug. I use formidable without express or connect and it is impossible for me to accept same-named fields. I will try the patch provided a few months ago but I'd prefer to use unpatched formidable.

I also vote for adding "[]" to the name as a de-facto standard.

[felixge]

This select tab with multiple fields problem is definitely a bug.

No, you are misunderstanding the current API.

I use formidable without express or connect and it is impossible for me to accept same-named fields.

That's not true. You can listen to the 'file' event of the form, and you will receive one event per file, regardless of the field name.

This doesn't mean that I won't change the API, apparently most people prefer magic over predictable outcomes, but please don't spread FUD.

I'm sorry, I didn't know about the event solution. i missed that in the docs. One would like to just have the fields in an obj, not go to the trouble of setting event handlers. It isn't a bug, just a pretty big inconvienence.

[fideloper]

For clarity (And I'm aware this is an old thread), you can add and event listen for the "file" event, emitted by formidable, to capture every file rather than use the callback with the formidable.parse() method:
(And please correct me if I'm mistaken)

var form = new formidable.IncomingForm();
form.uploadDir = '/some/path/to/directory';

form.addListener('file', function(file) {
  console.log('File Fired');
  console.log(file);
});

form.parse(req, function(err, fields, files) {
//Code here
}

[jacklynrose]

I'm wanting to use formidable with normal arrays of fields (not file fields), so I'm working on a fork now, I found the perfect spot for the code to go. I'll do a pull request in a second when I'm done. It will let you do things like:

<input name="tags[]" value="first tag" />
<input name="tags[]" value="second tag" />
<input name="tags[]" value="third tag" />

And then in the fields parameter of the cb we'll get tags:["first tag","second tag","third tag"] instead of what we're currently getting which is "tags[]":"third tag"

I'll post a comment once I've finished and made the pull request

[jacklynrose]

I've submitted the pull request: #77