Instantiate a Class from a String in Rails
Rails classes need to be called dynamically sometimes. Learn how to do it using the constantize inflector.
Sometimes you want your class names to be dynamic. Rails has a nice constantize inflector that makes this easy.
In the simplest of examples, let's just say you have a "post" string and you want to load the Post class from it. Something like the following should work great.
str = "post"
new_class_instance = str.constantize.newWe can get a little wild. Let's say you have a multi-word string and want to constantize and then instantiate it.
str = "posts controller"
new_class_instance = str.titleize.gsub(/\ /, '').constantize.newEssentially, this just shows you want a properly-cased string (the string equivalent of the class name) before you call constantize.
Keep Reading
Render an Inline SVG in Rails (or Middleman)
You can avoid multiple requests to your server by rendering SVG images inline to the rest of your HTML.
Use Slack For Rails Error Notification
Post a message to one of your Slack channels when your Rails app encounters a 500 error.
Order Rails Query by Virtual Attribute
Rails' scopes don't work well with virtual attributes since they resolve to a SQL query. Instead you can throw them in an array and then sort by a virtual attribute.