Add validation to slack settings (adapted from old slack plugin)

config/locales/server.en.yml

@@ -14,6 +14,9 @@ en:
     chat_integration_slack_icon_url: 'Icon to post to slack with (defaults to forum logo)'
     chat_integration_slack_access_token: 'Token if you are using the Web API instead of webhooks'
 
+    errors:
+      chat_integration_slack_api_configs_are_empty: "You must enter either an outbound webhook URL, or an access token"
+
     #######################################
     ######### TELEGRAM SETTINGS ###########
     #######################################

config/settings.yml

@@ -12,8 +12,10 @@ plugins:
 #######################################
   chat_integration_slack_enabled:
     default: false
+    validator: "ChatIntegrationSlackEnabledSettingValidator"
   chat_integration_slack_outbound_webhook_url:
     default: ''
+    regex: '^https:\/\/hooks\.slack\.com\/services\/.+$'
   chat_integration_slack_excerpt_length:
     default: 400
   chat_integration_slack_icon_url:

lib/validators/chat_integration_slack_enabled_setting_validator.rb

@@ -0,0 +1,16 @@
+class ChatIntegrationSlackEnabledSettingValidator
+  def initialize(opts={})
+    @opts = opts
+  end
+
+  def valid_value?(val)
+    return true if val == 'f'
+    return false if SiteSetting.chat_integration_slack_outbound_webhook_url.blank? && SiteSetting.chat_integration_slack_access_token.blank?
+    true
+  end
+
+  def error_message
+      I18n.t('site_settings.errors.chat_integration_slack_api_configs_are_empty')
+  end
+
+end

plugin.rb

@@ -5,6 +5,8 @@
 
 enabled_site_setting :chat_integration_enabled
 
+# Site setting validators must be loaded before initialize
+require_relative "lib/validators/chat_integration_slack_enabled_setting_validator"
 
 after_initialize do