fix: inline origin resolution, drop original dependency (#281)

lib/eventsource.js

@@ -1,4 +1,3 @@
-var original = require('original')
 var parse = require('url').parse
 var events = require('events')
 var https = require('https')
@@ -157,8 +156,8 @@ function EventSource (url, eventSourceInitDict) {
           _emit('error', new Event('error', {status: res.statusCode, message: res.statusMessage}))
           return
         }
-        var prevOrigin = original(url)
-        var nextOrigin = original(location)
+        var prevOrigin = getOrigin(url)
+        var nextOrigin = getOrigin(location)
         hasNewOrigin = prevOrigin !== nextOrigin
         if (res.statusCode === 307) reconnectUrl = url
         url = location
@@ -280,7 +279,7 @@ function EventSource (url, eventSourceInitDict) {
         _emit(type, new MessageEvent(type, {
           data: data.slice(0, -1), // remove trailing newline
           lastEventId: lastEventId,
-          origin: original(url)
+          origin: getOrigin(url)
         }))
         data = ''
       }
@@ -471,3 +470,16 @@ function removeUnsafeHeaders (headers) {
 
   return safe
 }
+
+/**
+ * Transform an URL to a valid origin value.
+ *
+ * @param {String|Object} url URL to transform to it's origin.
+ * @returns {String} The origin.
+ * @api private
+ */
+function getOrigin (url) {
+  if (typeof url === 'string') url = parse(url)
+  if (!url.protocol || !url.hostname) return 'null'
+  return (url.protocol + '//' + url.host).toLowerCase()
+}