refactor: Use http client for slack authentication

packages/backend/src/apps/slack/authentication.ts

@@ -1,22 +1,38 @@
 import type { IAuthentication, IApp, IJSONObject } from '@automatisch/types';
-import { WebClient } from '@slack/web-api';
+import HttpClient from '../../helpers/http-client';
+import qs from 'qs';
 
 export default class Authentication implements IAuthentication {
   appData: IApp;
   connectionData: IJSONObject;
-  client: WebClient;
+  client: HttpClient;
+  static requestOptions: IJSONObject = {
+    headers: {
+      'Content-Type': 'application/x-www-form-urlencoded',
+    },
+  };
 
   constructor(appData: IApp, connectionData: IJSONObject) {
-    this.client = new WebClient();
+    this.client = new HttpClient({ baseURL: 'https://slack.com/api' });
 
     this.connectionData = connectionData;
     this.appData = appData;
   }
 
   async verifyCredentials() {
-    const { bot_id: botId, user: screenName } = await this.client.auth.test({
-      token: this.connectionData.accessToken as string,
-    });
+    const response = await this.client.post(
+      '/auth.test',
+      qs.stringify({ token: this.connectionData.accessToken }),
+      Authentication.requestOptions
+    );
+
+    if (response.data.ok === false) {
+      throw new Error(
+        `Error occured while verifying credentials: ${response.data.error}.(More info: https://api.slack.com/methods/auth.test#errors)`
+      );
+    }
+
+    const { bot_id: botId, user: screenName } = response.data;
 
     return {
       botId,
@@ -27,9 +43,11 @@ export default class Authentication implements IAuthentication {
 
   async isStillVerified() {
     try {
-      await this.client.auth.test({
-        token: this.connectionData.accessToken as string,
-      });
+      await this.client.post(
+        '/auth.test',
+        qs.stringify({ token: this.connectionData.accessToken }),
+        Authentication.requestOptions
+      );
 
       return true;
     } catch (error) {