Slack Event Reminders Template

This code is not meant to be used as-is.

This template is meant to create the general setup we use at Virtual Coffee for our event reminders in Slack. You'll still need to write some code in order to use this template in any meaningful way.

How to use this template:

• Click the "Use this template" button above

• Customize the getEvents function to get your events

• Customize the output in the event reminders function

• Connect your site to Netlify

• Once your site is up on Netlify, follow these steps to create a Slack app:

  • Go to the new Slack App page
  • Select "From an app manifest"
  • Copy the following code, replace your-netlify-site.netlify.app with your site url, and paste it in:

  display_information:
    name: Event Reminders App
    description: Event Reminders for All!
    background_color: '#c55100'
  features:
    bot_user:
      display_name: Event Reminders App
      always_online: true
  oauth_config:
    scopes:
      bot:
        - chat:write
        - chat:write.public
  settings:
    interactivity:
      is_enabled: true
      request_url: https://your-netlify-site.netlify.app/slack-interactivity
    org_deploy_enabled: false
    socket_mode_enabled: false
    token_rotation_enabled: false

• After the App is created, go to OAuth & Permissions, and in the OAuth Tokens for Your Workspace section, and install it to your workspace. Once it's installed, in the same section you'll have a Bot User OAuth Token that we'll need for posting messages.

• In Slack, go to the channel you'd like to post to, click on the title to open up the channel information, and scroll all the way to the bottom to get your Channel ID

• In the Netlify admin, go to Settings -> Build and Deploy -> Environment, and add the following environment variables:

  • SLACK_BOT_TOKEN - the Bot User OAuth Token value
  • SLACK_ANNOUNCEMENTS_CHANNEL - the Channel ID

• After you've added the environment variables, you'll have to redeploy the site. Go to Deploys -> Trigger Deploy.

At this point, you can test your integration by going to https://your-netlify-site.netlify.app/event-reminders?type=weekly. If all is well, you should have a message in your Slack!

You can watch the log of your function on the netlify admin by going to Functions -> event-reminders-background. This will output messages if something is failing behind the scenes.

Cron Job Schedule

Now we just need to set up a schedule for running these functions. At Virtual Coffee, we use cron-job.org, a free service for cron jobs. Here are our settings:

Event reminders hourly

• URL: https://your-netlify-site.netlify.app/event-reminders?type=hourly
• Schedule: Every hour at 50 minutes past the hour
• Crontab: 50 * * * *

Event Reminders Daily

• URL: https://your-netlify-site.netlify.app/event-reminders?type=daily
• Schedule: Every day at 8am
• Crontab: 0 8 * * *

Event Reminders Weekly

• URL: https://your-netlify-site.netlify.app/event-reminders?type=weekly
• Schedule: Every Monday at 8am
• Crontab: 0 8 * * 1

Local development

You may find it easier to develop locally. This can be done using the Netlify CLI.

Installing the Netlify CLI

The Netlify CLI allows users to run a local version of the Netlify environment for local development. You can even share your locally-running app with other people on the internet!!

To install:

npm i -g netlify-cli

If you have previously installed the Netlify CLI, you should update it to the latest version:

npm i -g netlify-cli@latest

Setting up your .env

Use the following command to create a local .env file.

cp .env-example .env

Then open the new file (.env) and update SLACK_BOT_TOKEN and SLACK_ANNOUNCEMENTS_CHANNEL.

Installing package dependencies

Once you have the Netlify CLI installed, you're ready to install the local dependencies! Run the following command:

yarn

At this point you're ready to roll! Run the following command to get rolling!

netlify dev

This will create a local server running at http://localhost:8888/. You can now visit your function directly (ie go to http://localhost:8888/event-reminders?type=weekly), and see output right in your terminal!