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+# Backend API
+
+Provides a set of helper functions to integrate the recipe into [Ferdi](https://getferdi.com).
+
+## Ferdi Backend Class Methods
+* [validateUrl](#user-content-validateurl)
+* [overrideUserAgent](#user-content-overrideuseragent)
+
+## Events
+* [webview events](#user-content-events)
+
+### validateUrl(URL)
+Validate if the given URL is a valid service instance.  
+
+#### Arguments
+1. `string` URL
+
+#### Returns
+[`Promise`](https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/Promise)
+
+#### Usage
+
+```js
+// RocketChat integration
+module.exports = Ferdi => class RocketChat extends Ferdi {
+  async validateUrl(url) {
+    try {
+      const resp = await window.fetch(`${url}/api/info`, {
+        method: 'GET',
+        headers: {
+          'Content-Type': 'application/json',
+        },
+      });
+      const data = await resp.json();
+
+      return Object.hasOwnProperty.call(data, 'version');
+    } catch (err) {
+      console.error(err);
+    }
+
+    return false;
+  }
+};
+```
+
+### overrideUserAgent()
+Validate if the given URL is a valid service instance.  
+
+#### Returns
+`Boolean`
+
+#### Usage
+
+```js
+// Discord integration
+module.exports = Ferdi => class Discord extends Ferdi {
+  overrideUserAgent() {
+    const useragent = window.navigator.userAgent;
+
+    // Quick and dirty hackfix
+    const parts = useragent.split('(KHTML, like Gecko)');
+
+    return parts.join('(KHTML, like Gecko) discord/0.0.248').replace('Electron', 'Discord').replace('Ferdi', 'Discord');
+  }
+};
+
+```
+
+### Events
+Ferdi recipes can hook into the [electron webview events](https://electron.atom.io/docs/api/webview-tag/#dom-events) to trigger custom functions.
+
+This is necessary for services like TweetDeck where custom URL forwarding is needed during login.
+
+#### Usage
+```js
+module.exports = Ferdi => class Tweetdeck extends Ferdi {
+  events = {
+    'did-get-redirect-request': '_redirectFix',
+  }
+
+  _redirectFix(event) {
+    if (event.newURL !== undefined && event.oldURL !== undefined && event.isMainFrame) {
+      if (event.isMainFrame) {
+        setTimeout(() => this.send('redirect-url', event.newURL), 100);
+        event.preventDefault();
+      }
+    }
+  }
+};
+```