A sample app that uses slack-ruby-bot-server-events to implement and respond to Slack Events API, Interactive Message Buttons and Slash Commands.
Create .env file with the following settings.
SLACK_CLIENT_ID=...
SLACK_CLIENT_SECRET=...
SLACK_SIGNING_SECRET=...
SLACK_VERIFICATION_TOKEN=...
Get the values from from your app's Basic Information settings.
Run bundle install and foreman start.
Register your app via OAuth workflow from localhost:5000.
Expose the local server port 5000 to receive Slack events using ngrok.
ngrok http 5000
Copy the URL, e.g. https://79f0f6335438.ngrok.io, and use it as the prefix for your events, slash commands, and interactive message buttons.
See config/initializers/slack_ruby_bot_server.rb for the required OAuth scopes. If you get Slack::Web::Api::Errors::MissingScope: missing_scope errors, you are missing a scope in your app configuration.
Set the Request Url in your app's Features under Event Subscriptions, e.g. https://79f0f6335438.ngrok.io/api/slack/event. When you change this URL, Slack will POST a verification challenge to /api/slack/event, which should succeed.
Subscribe to member_joined_channel and member_left_channel events.
Invite the bot to a channel. Add/remove some other members. The welcome message is posted from lib/events/member_joined_channel.rb every time a user joins.
A default handler is also fired on all other events in lib/events/default.rb producing log output.
11:49:56 web.1 | I, [2020-07-19T11:49:56.933931 #72370] INFO -- : Successfully connected team dblock (T04KB5WQH) to https://dblockdotorg.slack.com.
11:53:10 web.1 | I, [2020-07-19T11:53:10.607301 #72370] INFO -- : User test_app joined events.
11:53:17 web.1 | I, [2020-07-19T11:53:17.786968 #72370] INFO -- : User dblockplayplay joined events.
Create a /ping Slash command. Set the Request URL, e.g. https://79f0f6335438.ngrok.io/api/slack/command.
There's no need to invite the bot to a channel. Try /ping, the bot will respond with pong from lib/slash_commands/ping.rb.
A default handler is also fired on all other slash commands in lib/slash_commands/default.rb producing log output.
20:17:02 web.1 | I, [2020-07-19T20:17:02.678409 #77259] INFO -- : Successfully connected team dblock (T04KB5WQH) to https://dblockdotorg.slack.com.
20:17:05 web.1 | I, [2020-07-19T20:17:05.703699 #77259] INFO -- : Received a ping.
Set the Request Url in your app's Features under Interactivity & Shortcuts, e.g. https://79f0f6335438.ngrok.io/api/slack/action. Create an "on messages" shortcut, set the ID to count-letters.
There's no need to invite the bot to a channel. Choose the "Count Letters" shortcut, the bot will respond with an ephemeral message from lib/actions/count_letters.rb.
A default handler is also fired on all other actions in lib/actions/default.rb producing log output.
23:42:21 web.1 | I, [2020-07-19T23:42:21.394965 #78955] INFO -- : Successfully connected team dblock (T04KB5WQH) to https://dblockdotorg.slack.com.
23:43:43 web.1 | I, [2020-07-19T23:43:43.978877 #78955] INFO -- : Counting letters in "The red brown fox jumped over a lazy dog."
Copyright Daniel Doubrovkine, 2020