Add FormData under melange.dom

Changes.md

@@ -45,6 +45,9 @@ Unreleased
   ([#1246](https://github.com/melange-re/melange/pull/1246))
 - `melange.node`: bind to all supported Node.js `Buffer` encodings in
   `Node.Buffer` ([#1246](https://github.com/melange-re/melange/pull/1246))
+- `melange.js`: Add `Js.FormData` with bindings to the
+  [FormData](https://developer.mozilla.org/en-US/docs/Web/API/FormData) API
+  ([#1153](https://github.com/melange-re/melange/pull/1153))
 
 4.0.1 2024-06-07
 ---------------

jscomp/runtime/js.pre.ml

@@ -35,10 +35,9 @@
     It contains all bindings into [Js] namespace.
 
     {[
-      [| 1;2;3;4|]
-      |. Js.Array2.map (fun x -> x + 1 )
-      |. Js.Array2.reduce (+) 0
-      |. Js.log
+      [| 1; 2; 3; 4 |]
+      |> Js.Array.map ~f:(fun x -> x + 1)
+      |> Js.Array.reduce ~f:( + ) ~init:0
     ]}
 *)
 
@@ -143,4 +142,5 @@ module WeakSet = Js_weakset
 module Map = Js_map
 module WeakMap = Js_weakmap
 module Iterator = Js_iterator
+module FormData = Js_formData
 module OO = Js_OO

jscomp/runtime/js.pre.mli

@@ -232,6 +232,9 @@ module WeakMap = Js_weakmap
 module Iterator = Js_iterator
 (** Bindings to functions on [Iterator] *)
 
+module FormData = Js_formData
+(** Bindings to FormData *)
+
 (**/**)
 
 module OO = Js_OO

jscomp/runtime/js_formData.ml

@@ -0,0 +1,117 @@
+(* Copyright (C) 2024- Authors of Melange
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * In addition to the permissions granted to you by the LGPL, you may combine
+ * or link a "work that uses the Library" with a publicly distributed version
+ * of this file to produce a combined library or application, then distribute
+ * that combined work under the terms of your choosing, with no requirement
+ * to comply with the obligations normally placed on you by section 4 of the
+ * LGPL version 3 (or the corresponding section of a later version of the LGPL
+ * should you choose to use a later version).
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *)
+
+(* Provides a way to easily construct a set of key/value pairs representing
+   form fields and their values, which can then be sent using
+   `XMLHttpRequest.send()`. It uses the same format a form would use if the
+   encoding type were set to "multipart/form-data". *)
+
+type t
+type file
+type blob
+
+type entryValue
+(** The values returned by the `get{,All}` and iteration functions is either a
+    string or a Blob. Melange uses an abstract type and defers to users of the
+    API to handle it according to their application needs. *)
+
+external make : unit -> t = "FormData"
+[@@mel.new]
+(** [make ()] creates a new [FormData] object, initially empty. *)
+
+external append :
+  name:string ->
+  value:
+    ([ `String of string | `Object of < .. > Js.t | `Dict of _ Js.dict ]
+    [@mel.unwrap]) ->
+  ?filename:string ->
+  unit = "append"
+[@@mel.send.pipe: t]
+(** [append t ~name ~value] appends a new value onto an existing key inside a
+    FormData object, or adds the key if it does not already exist. *)
+
+external appendBlob :
+  name:string ->
+  value:([ `Blob of blob | `File of file ][@mel.unwrap]) ->
+  ?filename:string ->
+  unit = "append"
+[@@mel.send.pipe: t]
+(** [appendBlob t ~name ~value] appends a new value onto an existing key inside
+    a FormData object, or adds the key if it does not already exist. This
+    method differs from [append] in that instances in the Blob hierarchy can
+    pass a third filename argument. *)
+
+external delete : name:string -> unit = "delete"
+[@@mel.send.pipe: t]
+(** [delete t ~name] deletes a key and its value(s) from a FormData object. *)
+
+external get : name:string -> entryValue option = "get"
+[@@mel.send.pipe: t] [@@mel.return null_to_opt]
+(** [get t ~name] returns the first value associated with a given key from
+    within a FormData object. If you expect multiple values and want all of
+    them, use {!getAll} instead. *)
+
+external getAll : name:string -> entryValue array = "getAll"
+[@@mel.send.pipe: t]
+(** [getAll ~name] returns all the values associated with a given key from
+    within a FormData object. *)
+
+external set :
+  name:string ->
+  ([ `String of string | `Object of < .. > Js.t | `Dict of _ Js.dict ]
+  [@mel.unwrap]) ->
+  unit = "set"
+[@@mel.send.pipe: t]
+(** [set t ~name ~value] sets a new value for an existing key inside a FormData
+    object, or adds the key/value if it does not already exist. *)
+
+external setBlob :
+  name:string ->
+  ([ `Blob of blob | `File of file ][@mel.unwrap]) ->
+  ?filename:string ->
+  unit = "set"
+[@@mel.send.pipe: t]
+(** [setBlob t ~name ~value ?filename] sets a new value for an existing key
+    inside a FormData object, or adds the key/value if it does not already
+    exist. This method differs from [set] in that instances in the Blob
+    hierarchy can pass a third filename argument. *)
+
+external has : name:string -> bool = "has"
+[@@mel.send.pipe: t]
+(** [has ~name] returns whether a FormData object contains a certain key. *)
+
+external keys : string Js.iterator = "keys"
+[@@mel.send.pipe: t]
+(** [keys t] returns an iterator which iterates through all keys contained in
+    the FormData. The keys are strings. *)
+
+external values : entryValue Js.iterator = "values"
+[@@mel.send.pipe: t]
+(** [values t] returns an iterator which iterates through all values contained
+    in the FormData. The values are strings or Blob objects. *)
+
+external entries : (string * entryValue) Js.iterator = "entries"
+[@@mel.send.pipe: t]
+(** [entries t] returns an iterator which iterates through all key/value pairs
+    contained in the FormData. *)