update MessageMedia.fromUrl (#811)

* fix MessageMedia.fromUrl docs

* use content-type as fallback

* set filename based on url

* fix empty filename

* wrap expression in parentheses

* hotfix

* JSDoc fix

* fix for jsdog

* eslint gets retirement home

Co-authored-by: Rajeh Taher <rajeh@reforward.dev>
Co-authored-by: Aliyss Snow <33941859+Aliyss@users.noreply.github.com>

index.d.ts

@@ -692,6 +692,7 @@ declare namespace WAWebJS {
 
     export interface MediaFromURLOptions {
         client?: Client
+        filename?: string
         unsafeMime?: boolean
         reqOptions?: RequestInit
     }

src/structures/MessageMedia.js

@@ -5,7 +5,7 @@ const path = require('path');
 const mime = require('mime');
 const fetch = require('node-fetch');
 const { URL } = require('url');
-
+const { Client } = require('whatsapp-web.js'); // eslint-disable-line no-unused-vars
 /**
  * Media attached to a message
  * @param {string} mimetype MIME type of the attachment
@@ -50,27 +50,25 @@ class MessageMedia {
      * Creates a MessageMedia instance from a URL
      * @param {string} url
      * @param {Object} [options]
-     * @param {number} [options.unsafeMime=false]
-     * @param {object} [options.client]
+     * @param {boolean} [options.unsafeMime=false]
+     * @param {string} [options.filename]
+     * @param {Client} [options.client]
      * @param {object} [options.reqOptions]
      * @param {number} [options.reqOptions.size=0]
      * @returns {Promise<MessageMedia>}
      */
     static async fromUrl(url, options = {}) {
-        let mimetype;
+        const pUrl = new URL(url);
+        let mimetype = mime.getType(pUrl.pathname);
 
-        if (!options.unsafeMime) {
-            const pUrl = new URL(url);
-            mimetype = mime.getType(pUrl.pathname);
-
-            if (!mimetype)
-                throw new Error('Unable to determine MIME type');
-        }
+        if (!mimetype && !options.unsafeMime)
+            throw new Error('Unable to determine MIME type using URL. Set unsafeMime to true to download it anyway.');
 
         async function fetchData (url, options) {
             const reqOptions = Object.assign({ headers: { accept: 'image/* video/* text/* audio/*' } }, options);
             const response = await fetch(url, reqOptions);
             const mime = response.headers.get('Content-Type');
+            const name = response.headers.get('Content-Disposition')?.match(/((?<=filename=")(.*)(?="))/);
             let data = '';
 
             if (response.buffer) {
@@ -83,18 +81,21 @@ class MessageMedia {
                 data = btoa(data);
             }
             
-            return { data, mime };
+            return { data, mime, name };
         }
 
         const res = options.client
             ? (await options.client.pupPage.evaluate(fetchData, url, options.reqOptions))
             : (await fetchData(url, options.reqOptions));
 
+        const filename = options.filename ??
+            (res.name ? res.name[0] : (pUrl.pathname.split('/').pop() || 'file'));
+        
         if (!mimetype)
             mimetype = res.mime;
 
-        return new MessageMedia(mimetype, res.data, null);
+        return new MessageMedia(mimetype, res.data, filename);
     }
 }
 
-module.exports = MessageMedia;
+module.exports = MessageMedia;