Make server more customizable via config

index.js

@@ -3,7 +3,19 @@ const cookieParser = require('cookie-parser')
 const discord = require("discord.js");
 const Auth = require("discord-oauth2");
 const crypto = require('crypto');
-const config = require("./config.json");
+
+const {
+    CLIENT_ID,
+    CLIENT_SECRET,
+    TOKEN,
+    GUILD_ID,
+
+    PROTOCOL,
+    HOSTNAME,
+    LOGIN_PATH,
+    CALLBACK_PATH,
+    PORT
+} = require("./config.json");
 
 const client = new discord.Client({
     ws: {
@@ -14,61 +26,77 @@ const client = new discord.Client({
 });
 const app = express();
 const auth = new Auth({
-    clientId: config.cid,
-    clientSecret: config.secret
+    clientId: CLIENT_ID,
+    clientSecret: CLIENT_SECRET
 });
 
+/*
+ *  Make sure to add a this URL to your Discord Application like show on this page:
+ *  https://discordjs.guide/oauth2/#getting-an-oauth2-url
+ */
+const redirectUri = `${PROTOCOL}://${HOSTNAME}:${PORT}${CALLBACK_PATH}`;
+
 app.use(cookieParser());
 
-app.get("/login", (req, res) => {
-    var state = crypto.randomBytes(64).toString('hex');
+app.get(LOGIN_PATH, (req, res) => {
+    const state = crypto.randomBytes(64).toString('hex');
     res.cookie("state", state);
     res.redirect(auth.generateAuthUrl({
         scope: ["connections", "identify"],
         state,
-        redirectUri: "http://localhost:8080/callback"
+        redirectUri
     }));
 });
 
-app.get("/callback", async (req, res) => {
+app.get(CALLBACK_PATH, async (req, res) => {
     const { code, state } = req.query;
+    // Alternatively, use res.redirect() to use a fancier error page. Same thing goes for all the other error handlers.
     if(state !== req.cookies.state) return res.status(400).send("Wrong state");
     try {
         var token = await auth.tokenRequest({
             code,
             scope: [ "connections", "identify" ],
             grantType: "authorization_code",
-            redirectUri: "http://localhost:8080/callback"
+            redirectUri
         });
     } catch(e) {
         return res.status(403).send("Invalid code");
     }
-    var connections = await auth.getUserConnections(token.access_token);
-    var reddit = connections.filter(val => val.type === "reddit");
-    if(!reddit) return res.send("No reddit connection");
+    const connections = await auth.getUserConnections(token.access_token);
+
+    let reddit = connections.filter(val => val.type === "reddit");
+    if(!reddit[0]) return res.send("No reddit connection found");
     reddit = reddit[0];
-    var user = await auth.getUser(token.access_token);
+    const user = await auth.getUser(token.access_token);
 
     try {
-        var guild = await client.guilds.fetch(config.guild);
+        var guild = await client.guilds.fetch(GUILD_ID);
     } catch(e) {
-        return res.status(500).send("Guild not found");
+        return res.status(500).send("Discord guild not found");
     }
     try {
         var member = await guild.members.fetch(user.id);
     } catch(e) {
-        return res.status(403).send("Member not found");
+        return res.status(403).send("Discord member not found");
     }
     try {
+        /*
+        Add whatever discord logic you want here. You could for example add a "Verfied" role:
+            await member.roles.add("roleId")
+        or DM the user: (make sure to do error handling if bot can't DM user)
+            await member.send("Succesfully verified you as reddit user u/" + reddit.name + " in guild " + guild.name)
+
+        If you're gonna change the user's nickname like this, remember to limit their "Change nickname" perms - otherwise they can just change it back.
+        */
         await member.setNickname("u/" + reddit.name);
     } catch(e) {
-        return res.status(500).send("Missing nickname permission");
+        return res.status(500).send("Couldn't change nickname.");
     }
-    res.send("Done");
+    res.send("Success!");
 });
 
-client.login(config.token);
+client.login(TOKEN);
 
-app.listen(8080, () => {
-    console.log("http://localhost:8080/login");
-})
+app.listen(PORT, () => {
+    console.log("Listening on port", PORT);
+});