slack_notification.rb

class SlackNotification
  class UnknownSlackChannel < StandardError; end

  WEBHOOK_URLS = Rails.configuration.x.slack_webhook_urls

  def initialize(webhook_url:)
    @notifier = Slack::Notifier.new(webhook_url)
  end

  def self.for_channel(channel_name)
    key = channel_name.to_s.remove_prefix('#').to_sym
    webhook_url = WEBHOOK_URLS.fetch(key)

    new(webhook_url:)
  rescue KeyError => e
    raise UnknownSlackChannel, e
  end

  def send_text!(message, **options)
    unless message.is_a? String
      raise ArgumentError, message
    end

    @notifier.ping(message, link_names: true, **options)
  end

  def send_blocks!(*blocks)
    @notifier.post(blocks: blocks.map(&:to_h))
  end
end