Add http handler example

.env.example

@@ -1,3 +1,4 @@
 SLACK_SIGNING_SECRET=<your-signing-secret>
 SLACK_BOT_TOKEN=xoxb-<your-bot-token>
-PORT=3000
+WEBHOOK_TOKEN=123456789
+PORT=3000

README.md

@@ -36,7 +36,8 @@ Follow these steps to set up this bot on your Slack
    send chat messages:
 
    - Go to _OAuth and Permissions_ in the left menu
-   - Add scope `users:read` and `chat:write`
+   - Required scopes `commands`, `users:read` and `chat:write`.
+   - Consider scopes `app_mentions:read`, `im:read`, `im:write`, `mpim:read`, `mpim:write`, `chat:write.public`, `links:write`, `incoming-webhook` (simplifies life and allows you to do basic interaction/conversation)
 
    For our bot to be able to respond to interactive messages, we must enable
    interactivity:
@@ -49,7 +50,14 @@ Follow these steps to set up this bot on your Slack
    variables on the server we set up in step 1:
 
    - `SLACK_SIGNING_SECRET`: Found in _Basic Information_ -> _Signing Secret_
-   - `SLACK_BOT_TOKEN`: Found in _Oath and Permissions_ -> _Bot User OAuth Access Token_
+   - `SLACK_BOT_TOKEN`: Found in _Oauth and Permissions_ -> _Bot User OAuth Access Token_
+
+   For our HTTP webhook receiver, we also want to set the following
+   environment variables:
+
+   - `WEBHOOK_TOKEN`: Any string that will work as a token for calling our endpoint.
+   - `SLACK_WEBHOOK_CHANNEL`: The channel (or user) to receive data from webhooks,
+     e.g. `#random` or `@myhandle`.
 
 ## Develop
 

app.json

@@ -3,14 +3,24 @@
   "description": "A starter for making a Slack bot",
   "env": {
     "SLACK_BOT_TOKEN": {
-      "description": "Found in Slack/New App/Oath and Permissions. Can be set later",
+      "description": "Found in Slack/New App/Oauth and Permissions. Can be set later",
       "value": "",
       "required": false
     },
     "SLACK_SIGNING_SECRET": {
       "description": "Found in Slack/New App/Basic Information. Can be set later",
       "value": "",
       "required": false
+    },
+    "SLACK_WEBHOOK_CHANNEL": {
+      "description": "Channel to report incoming webhook data to. Can be set later.",
+      "value": "#random",
+      "required": false
+    },
+    "WEBHOOK_TOKEN": {
+      "description": "A random secret token you create, for other services to communicate to Slack via your bot. Can be set later.",
+      "value": "a-secret",
+      "required": false
     }
   },
   "repository": "https://github.com/tomfa/slack-app-starter",

src/app.ts

@@ -1,12 +1,16 @@
+import { Receiver } from "@slack/bolt";
+
 require("dotenv").config();
 
 import { ChatBot } from "./types";
 
 export const createApp = (config: {
   slackBotToken: string;
   slackSigningSecret: string;
+  receiver: Receiver | undefined;
 }): ChatBot =>
   new ChatBot({
     token: config.slackBotToken,
     signingSecret: config.slackSigningSecret,
+    receiver: config.receiver,
   });

src/http.ts

@@ -0,0 +1,27 @@
+import { ChatBot } from "./types";
+
+import { ExpressReceiver } from "@slack/bolt";
+
+export const createHandler = (props: { signingSecret: string }) =>
+  new ExpressReceiver(props);
+
+export const addHttpHandlers = (args: {
+  app: ChatBot;
+  receiver: ExpressReceiver;
+  allowedTokens: string[];
+  dmChannel: string;
+}) => {
+  args.receiver.router.get("/secret-page", (req, res) => {
+    const token = req.query.token as string;
+    const hasAccess = token && args.allowedTokens.includes(token);
+    if (!hasAccess) {
+      console.log(`Attempted accessing http handler without valid token`);
+      return res.send("OK");
+    }
+    args.app.dm({
+      user: args.dmChannel,
+      text: "I suppose there will be a funny little PR tomorrow",
+    });
+    res.send(`I have informed our master of your arrival`);
+  });
+};

src/index.ts

@@ -1,17 +1,28 @@
-import { addEvents } from "./events";
-
 require("dotenv").config();
 
-import { addSlashCommands } from "./commands";
 import { createApp } from "./app";
+import { addEvents } from "./events";
+import { addSlashCommands } from "./commands";
+import { createHandler, addHttpHandlers } from "./http";
+
+const receiver = createHandler({
+  signingSecret: process.env.SLACK_SIGNING_SECRET!,
+});
 
 const app = createApp({
-  slackBotToken: process.env.SLACK_BOT_TOKEN as string,
-  slackSigningSecret: process.env.SLACK_SIGNING_SECRET as string,
+  slackBotToken: process.env.SLACK_BOT_TOKEN!,
+  slackSigningSecret: process.env.SLACK_SIGNING_SECRET!,
+  receiver,
 });
 
 addSlashCommands(app);
 addEvents(app);
+addHttpHandlers({
+  app,
+  receiver,
+  allowedTokens: [process.env.WEBHOOK_TOKEN!],
+  dmChannel: process.env.SLACK_WEBHOOK_CHANNEL || "#random",
+});
 
 (async () => {
   await app.start(process.env.PORT as string);