MiddlewareStackProxy is a proxy for the Rails middleware stack that allows you to configure middlewares in your application. It works basically as a command recorder, saving each command to be applied after initialization over the default middleware stack, so you can add, swap, or remove any middleware in Rails.

You can add your own middlewares by using the config.middleware.use method:

config.middleware.use Magical::Unicorns

This will put the Magical::Unicorns middleware on the end of the stack. You can use insert_before if you wish to add a middleware before another:

config.middleware.insert_before Rack::Head, Magical::Unicorns

There's also insert_after which will insert a middleware after another:

config.middleware.insert_after Rack::Head, Magical::Unicorns

Middlewares can also be completely swapped out and replaced with others:

config.middleware.swap ActionDispatch::Flash, Magical::Unicorns

And finally they can also be removed from the stack completely:

config.middleware.delete ActionDispatch::Flash
Methods
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Class Public methods
new(operations = [], delete_operations = [])

Source: show | on GitHub 

# File railties/lib/rails/configuration.rb, line 38
def initialize(operations = [], delete_operations = [])
  @operations = operations
  @delete_operations = delete_operations
end
Instance Public methods
delete(*args, &block)

Source: show | on GitHub 

# File railties/lib/rails/configuration.rb, line 61
def delete(*args, &block)
  @delete_operations << [__method__, args, block]
end
insert(*args, &block)
Alias for: insert_before
insert_after(*args, &block)

Source: show | on GitHub 

# File railties/lib/rails/configuration.rb, line 49
def insert_after(*args, &block)
  @operations << [__method__, args, block]
end
insert_before(*args, &block)
Also aliased as: insert

Source: show | on GitHub 

# File railties/lib/rails/configuration.rb, line 43
def insert_before(*args, &block)
  @operations << [__method__, args, block]
end
swap(*args, &block)

Source: show | on GitHub 

# File railties/lib/rails/configuration.rb, line 53
def swap(*args, &block)
  @operations << [__method__, args, block]
end
unshift(*args, &block)

Source: show | on GitHub 

# File railties/lib/rails/configuration.rb, line 65
def unshift(*args, &block)
  @operations << [__method__, args, block]
end
use(*args, &block)

Source: show | on GitHub 

# File railties/lib/rails/configuration.rb, line 57
def use(*args, &block)
  @operations << [__method__, args, block]
end
Instance Protected methods
delete_operations()

Source: show | on GitHub 

# File railties/lib/rails/configuration.rb, line 86
def delete_operations
  @delete_operations
end
operations()

Source: show | on GitHub 

# File railties/lib/rails/configuration.rb, line 82
def operations
  @operations
end