[telegram] Add constructor option, 'filepath'

Feature:

  The constructor option, 'filepath', allows us to remove
  the TelegramBot's behaviour of allowing users to pass in
  file-paths as arguments, as it involves some operations
  that might be (are) strongly against what a programmer wishes
  to achieve with the library.

  Expect this to be documented better in the near future.

Implementation:

  * Backwards compatible: The default behavior is not changed!

README.md

@@ -144,6 +144,7 @@ Emits `message` when a message arrives.
 | [options.onlyFirstMatch] | <code>Boolean</code> | <code>false</code> | Set to true to stop after first match. Otherwise, all regexps are executed |
 | [options.request] | <code>Object</code> |  | Options which will be added for all requests to telegram api.  See https://github.com/request/request#requestoptions-callback for more information. |
 | [options.baseApiUrl] | <code>String</code> | <code>https://api.telegram.org</code> | API Base URl; useful for proxying and testing |
+| [options.filepath] | <code>Boolean</code> | <code>true</code> | Allow passing file-paths as arguments when sending files,  such as photos using `TelegramBot#sendPhoto()`. |
 
 <a name="TelegramBot+startPolling"></a>
 

src/telegram.js

@@ -63,6 +63,8 @@ class TelegramBot extends EventEmitter {
    * @param {Object} [options.request] Options which will be added for all requests to telegram api.
    *  See https://github.com/request/request#requestoptions-callback for more information.
    * @param {String} [options.baseApiUrl=https://api.telegram.org] API Base URl; useful for proxying and testing
+   * @param {Boolean} [options.filepath=true] Allow passing file-paths as arguments when sending files,
+   *  such as photos using `TelegramBot#sendPhoto()`.
    * @see https://core.telegram.org/bots/api
    */
   constructor(token, options = {}) {
@@ -70,6 +72,7 @@ class TelegramBot extends EventEmitter {
     this.token = token;
     this.options = options;
     this.options.baseApiUrl = options.baseApiUrl || 'https://api.telegram.org';
+    this.options.filepath = typeof options.filepath === 'undefined' ? true : options.filepath;
     this._textRegexpCallbacks = [];
     this._onReplyToMessages = [];
     this._polling = null;
@@ -210,6 +213,12 @@ class TelegramBot extends EventEmitter {
           contentType: filetype.mime
         }
       };
+    } else if (!this.options.filepath) {
+      /**
+       * When the constructor option 'filepath' is set to
+       * 'false', we do not support passing file-paths.
+       */
+      fileId = data;
     } else if (fs.existsSync(data)) {
       fileName = path.basename(data);
       formData = {};

test/telegram.js

@@ -971,5 +971,13 @@ describe('TelegramBot', function telegramSuite() {
         assert.ok(is.array(resp.photo));
       });
     });
+    it('should not accept file-paths if disallowed with constructor option', function test() {
+      const tgbot = new TelegramBot(TOKEN, { filepath: false });
+      const photo = `${__dirname}/data/photo.gif`;
+      return tgbot.sendPhoto(USERID, photo).catch(err => {
+        // TODO: check for error in a better way
+        assert.ok(err.response.body.indexOf('Bad Request') !== -1);
+      });
+    });
   });
 }); // End Telegram