# Slack Bot Mention Edge Function

Building a Slack Bot that Handles Mentions.

The Slack Bot Mention Edge Function allows you to process mentions in Slack and respond accordingly.

## Configuring Slack apps

For your bot to seamlessly interact with Slack, you'll need to configure Slack Apps:

1. Navigate to the Slack Apps page.
2. Under "Event Subscriptions," add the URL of the `slack-bot-mention` function and click to verify the URL.
3. The Edge function will respond, confirming that everything is set up correctly.
4. Add `app-mention` in the events the bot will subscribe to.

## Creating the Edge Function

Deploy the following code as an Edge function using the CLI:

```bash
supabase secrets set \
  SLACK_TOKEN=<xoxb-0000000000-0000000000-01010101010nacho101010> \
  --project-ref nacho_slacker
```

Here's the code of the Edge Function, you can change the response to handle the text received:

```ts index.ts
import { WebClient } from 'npm:@slack/web-api@^7'
import { withSupabase } from 'npm:@supabase/server@^1'

const slackBotToken = Deno.env.get('SLACK_TOKEN') ?? ''
const botClient = new WebClient(slackBotToken)

console.log(`Slack URL verification function up and running!`)

// Slack calls this endpoint, so deploy with --no-verify-jwt.
export default {
  fetch: withSupabase({ auth: 'none' }, async (req) => {
    try {
      // Implement your Slack request signature verification here before trusting the payload
      // (validate `x-slack-signature` / `x-slack-request-timestamp` with your signing secret).
      const reqBody = await req.json()
      console.log(JSON.stringify(reqBody, null, 2))
      const { token, challenge, type, event } = reqBody

      if (type == 'url_verification') {
        return Response.json({ challenge })
      } else if (event.type == 'app_mention') {
        const { user, text, channel, ts } = event
        // Here you should process the text received and return a response:
        const response = await botClient.chat.postMessage({
          channel: channel,
          text: `Hello <@${user}>!`,
          thread_ts: ts,
        })
        return Response.json({ ok: true })
      }
    } catch (error) {
      return Response.json({ error: error.message }, { status: 500 })
    }
  }),
}
```