Added the ability to check whether the provided meetup groups actuall…

…y exist.

package.json

@@ -24,6 +24,7 @@
     "@nestjs/core": "^6.7.2",
     "@nestjs/platform-express": "^6.7.2",
     "@types/ical": "^0.6.1",
+    "axios": "^0.19.0",
     "ical": "^0.6.0",
     "ical-generator": "^1.9.2",
     "reflect-metadata": "^0.1.13",

src/controllers/calendar.controller.ts

@@ -8,9 +8,7 @@ import {
 import { Response } from "express";
 
 import { CalendarService } from "../services";
-
-const getMeetupICalUrl = (groupName: string): string =>
-    `https://www.meetup.com/${groupName}/events/ical/`;
+import { getMeetupICalUrl, checkMeetupGroupExists } from "../utils";
 
 @Controller()
 export class CalendarController {
@@ -29,6 +27,14 @@ export class CalendarController {
 
         // Parse the meetup groups, some validation about whether or not they exist would be nice...
         const groups = meetupGroups.split(",");
+        const result = await Promise.all(
+            groups.map(group => checkMeetupGroupExists(group)),
+        );
+        if (result.indexOf(false) > -1) {
+            throw new BadRequestException(
+                "One or more meetup groups were not found",
+            );
+        }
 
         console.log(`Getting events for: `, groups);
 

src/utils/index.ts

@@ -0,0 +1 @@
+export * from "./meetup.utils";

src/utils/meetup.utils.ts

@@ -0,0 +1,15 @@
+import Axios from "axios";
+
+export const getMeetupICalUrl = (groupName: string): string =>
+    `https://www.meetup.com/${groupName}/events/ical/`;
+
+export const checkMeetupGroupExists = async (
+    groupName: string,
+): Promise<boolean> => {
+    try {
+        await Axios.head(getMeetupICalUrl(groupName), { maxRedirects: 0 });
+        return true;
+    } catch (error) {
+        return false;
+    }
+};

yarn.lock

@@ -1106,7 +1106,7 @@ aws4@^1.8.0:
   resolved "https://registry.yarnpkg.com/aws4/-/aws4-1.9.0.tgz#24390e6ad61386b0a747265754d2a17219de862c"
   integrity sha512-Uvq6hVe90D0B2WEnUqtdgY1bATGz3mw33nH9Y+dmA+w5DHvUmBgkr5rM/KCHpCsiFNRUfokW/szpPPgMK2hm4A==
 
-[email protected]:
+[email protected], axios@^0.19.0:
   version "0.19.0"
   resolved "https://registry.yarnpkg.com/axios/-/axios-0.19.0.tgz#8e09bff3d9122e133f7b8101c8fbdd00ed3d2ab8"
   integrity sha512-1uvKqKQta3KBxIz14F2v06AEHZ/dIoeKfbTRkK1E5oqjDnuEerLmYTgJB5AiQZHJcljpg1TuRzdjDR06qNk0DQ==