This is a tiny Rails app that will get you the latest image from Psie Sucharki Facebook page right into your Slack channel. It uses Slack's slash commands and Facebook's Graph API under the hood.
You type in a command and get a picture in return. Here's a GIF of that happening.
You'll need Facebook, Slack, and a place to host this app.
Put it on the interwebz. Heroku is good for that.
Go to Slack's app builder and choose Custom Integration and then Slash Commands. You can use whatever command name you
like. Click Add. Set the request method to GET and the address to
your-apps-public-url/latest_post_url.
You'll need the token to configure your app, so store it somewhere safe for a while.
Visit Facebook developers app dashboard
and click Add A New App. Choose a name and the category for your app. Once
it's created, go to Settings > Basic.
Save App ID and App Secret. (You will have to type in your password to
reveal the App Secret.)
Put the Slack token and Facebook credentials as environment variables into your production environment. If you're using Heroku, consult their docs on config vars.
Have fun!
You need to set up the credentials from Slack and Facebook correctly for the app to work.
It will send back a message to the user via the Slack Bot when Slack token is invalid or when it has been denied access to the Facebook API so that they know what's going on.
Kasia Jarmołkowicz
MIT