implement FormData.get and FormData.getAll

[jdeniau]

The implementation is maybe very simplistic but it may do the job

See:

• get
• getAll

[coveralls]

Coverage increased (+0.1%) to 98.148% when pulling 48d93c2 on jdeniau:jd-feat-getAndGetAll into b16916a on form-data:master.

[jdeniau]

Th appveyor test is failing randomly I don't know why (I tried to amend and push another time, and it failed on another test case)

[yordis]

@alexindigo could you take a look to this mate. I need this feature to be able to publish a package and would be great if we could have it.

It seems that the Appveyor is failing because of permissions issues, but the PR is fine.

[yordis]

I am confused with this.

You use an array as the data structure but then you use it as an object

[jdeniau]

My bad !
It works because Javascript Array are objects, and thus it become attribute of an object, I will change this to a map ;)

[yordis]

@jdeniau actually I would use a list for this and create a list of objects.

I know that from data structure makes sense but following the spec I believe that append do not remove the previous one, if you read the spec when you append it keeps adding entries even when they could have the same name.

From documentation

Each FormData object has an associated entry list (a list of entries). It is initially the empty list.
An entry consists of a name and a value.

So maybe is better to have a list of objects

[
 { name: 'hello', value: 'world'}
]

I am trying to finish the spec and probably maybe would be better if you change the current implementation

So far,

function createEntry(name, value, filename) {
  // TODO: handle Blob and File
  // Related to https://xhr.spec.whatwg.org/#concept-formdata-entry

  // Case 1:
  // If value is a Blob object and not a File object, then set value to a new
  // File object, representing the same bytes, whose name attribute value is
  // "blob".

  // Case 2:
  // If value is (now) a File object and filename is given, then set value to a
  // new File object, representing the same bytes, whose name attribute value
  // is filename.

  var entry = {
    name: name,
    value: value,
  };

  return entry;
}

I created this functions because it seems that we will need to do some complex stuff with the entries https://xhr.spec.whatwg.org/#concept-formdata-entry

So basically for now you could do this._entries.push( createEntry(name, value, filename );

The filename come from the API, on set and append you will have two cases for the function

  void append(USVString name, USVString value);
  void append(USVString name, Blob blobValue, optional USVString filename);

So one expects just a value and the other one expects a File/Blob I guess.

[yordis]

Suggested change

	this._entryList = {};
	this._entryList = [];

We need to use a list rather than an array. The current spec allow you to append to the list multiple values for the same key

[yordis]

Append an object with the following shape

{ name: '', value: '' }

append do not remove previous entry, just do an append on the list.

Suggested change

	this._entryList[field].push(value);
	// move this function out of this scope, this is just so you have an idea about it.
	function createEntry(name, value, filename) {
	// TODO: handle Blob and File
	// Related to https://xhr.spec.whatwg.org/#concept-formdata-entry
	// Case 1:
	// If value is a Blob object and not a File object, then set value to a new
	// File object, representing the same bytes, whose name attribute value is
	// "blob".
	// Case 2:
	// If value is (now) a File object and filename is given, then set value to a
	// new File object, representing the same bytes, whose name attribute value
	// is filename.
	var entry = {
	name: name,
	value: value,
	};
	return entry;
	}
	const entry = createEntry(field, value, filename);
	this._entryList.push(entry);

[yordis]

From the spec

The get(name) method, when invoked, must return the value of the first entry whose name is name from the context object’s entry list, and null otherwise.

Do an Array.find

Suggested change

	return this._entryList[field] ? this._entryList[field][0] : null;
	var foundEntry = this._entryList.find(function(entry) {
	return entry.name === field;
	});
	return foundEntry === undefined ? null: foundEntry.value

[yordis]

From the spec

The getAll(name) method, when invoked, must return the values of all entries whose name is name, in order, from the context object’s entry list, and the empty list otherwise.

Do an Array.filter in the list.

Suggested change

	return this._entryList[field] || [];
	return this._entryList.reduce(function (acc, entry) {
	if(entry.name === field) {
	acc.push(entry.value);
	}
	return acc;
	}, []);

[yordis]

Hey @jdeniau, for me to be able to finish the other APIs I will need the changes that I suggest. Would be better for me to work on top what you did already rather than duplicating the work.

[jdeniau]

Looks good to me, I will work on this, but I did not quite well understand the [constructing the entry list(https://html.spec.whatwg.org/multipage/form-control-infrastructure.html#constructing-the-form-data-set) part 🤔

[yordis]

@jdeniau well that one is for the web actually.

FormData constructor expects an optional form.

If you pass a form you need to loop throw the list of inputs under that form and do an append of the entry where the entry name is the field name and the value is the field value based on some weird stuff.

But this code is only for NodeJS unless you are trying to monkey patch that as well.