Class: Utopia::Controller

Inherits:
Object
  • Object
show all
Defined in:
lib/utopia/controller.rb,
lib/utopia/controller/base.rb,
lib/utopia/controller/actions.rb,
lib/utopia/controller/respond.rb,
lib/utopia/controller/rewrite.rb,
lib/utopia/controller/variables.rb

Overview

A middleware which loads controller classes and invokes functionality based on the requested path.

Defined Under Namespace

Modules: Actions, Respond, Rewrite Classes: Base, Variables

Constant Summary collapse

CONTROLLER_RB =

The controller filename.

'controller.rb'.freeze
CONTENT_TYPE = 
HTTP::CONTENT_TYPE

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(app, root: Utopia::default_root, base: Controller::Base) ⇒ Controller

Returns a new instance of Controller.

Parameters:

  • root (String) (defaults to: Utopia::default_root) —

    The content root where controllers will be loaded from.

  • base (Class) (defaults to: Controller::Base) —

    The base class for controllers.



47
48
49
50
51
52
53
54
 
# File 'lib/utopia/controller.rb', line 47

def initialize(app, root: Utopia::default_root, base: Controller::Base)
	@app = app
	@root = root
	
	@controller_cache = Concurrent::Map.new
	
	@base = base
end

Instance Attribute Details

#app ⇒ Object (readonly)

Returns the value of attribute app.



56
57
58
 
# File 'lib/utopia/controller.rb', line 56

def app
  @app
end

Class Method Details

.[](request) ⇒ Object 



41
42
43
 
# File 'lib/utopia/controller.rb', line 41

def self.[] request
	request.env[VARIABLES_KEY]
end

Instance Method Details

#call(env) ⇒ Object 



141
142
143
144
145
146
147
148
149
150
151
 
# File 'lib/utopia/controller.rb', line 141

def call(env)
	env[VARIABLES_KEY] ||= Variables.new
	
	request = Rack::Request.new(env)
	
	if result = invoke_controllers(request)
		return result
	end
	
	return @app.call(env)
end

#freeze ⇒ Object 



58
59
60
61
62
63
64
65
 
# File 'lib/utopia/controller.rb', line 58

def freeze
	return self if frozen?
	
	@root.freeze
	@base.freeze
	
	super
end

#invoke_controllers(request) ⇒ Object

Invoke the controller layer for a given request. The request path may be rewritten.

Raises:

  • (ArgumentError) 


105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
 
# File 'lib/utopia/controller.rb', line 105

def invoke_controllers(request)
	request_path = Path.from_string(request.path_info)
	
	# The request path must be absolute. We could handle this internally but it is probably better for this to be an error:
	raise ArgumentError.new("Invalid request path #{request_path}") unless request_path.absolute?
	
	# The controller path contains the current complete path being evaluated:
	controller_path = Path.new
	
	# Controller instance variables which eventually get processed by the view:
	variables = request.env[VARIABLES_KEY]
	
	while request_path.components.any?
		# We copy one path component from the relative path to the controller path at a time. The controller, when invoked, can modify the relative path (by assigning to relative_path.components). This allows for controller-relative rewrites, but only the remaining path postfix can be modified.
		controller_path.components << request_path.components.shift
		
		if controller = lookup_controller(controller_path)
			# Don't modify the original controller:
			controller = controller.clone
			
			# Append the controller to the set of controller variables, updates the controller with all current instance variables.
			variables << controller
			
			if result = controller.process!(request, request_path)
				return result
			end
		end
	end
	
	# Controllers can directly modify relative_path, which is copied into controller_path. The controllers may have rewriten the path so we update the path info:
	request.env[Rack::PATH_INFO] = controller_path.to_s
	
	# No controller gave a useful result:
	return nil
end

#load_controller_file(uri_path) ⇒ Object

Loads the controller file for the given relative url_path.



75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
 
# File 'lib/utopia/controller.rb', line 75

def load_controller_file(uri_path)
	base_path = File.join(@root, uri_path.components)
	
	controller_path = File.join(base_path, CONTROLLER_RB)
	# puts "load_controller_file(#{path.inspect}) => #{controller_path}"
	
	if File.exist?(controller_path)
		klass = Class.new(@base)
		
		# base_path is expected to be a string representing a filesystem path:
		klass.const_set(:BASE_PATH, base_path.freeze)
		
		# uri_path is expected to be an instance of Path:
		klass.const_set(:URI_PATH, uri_path.dup.freeze)
		
		klass.const_set(:CONTROLLER, self)
		
		klass.class_eval(File.read(controller_path), controller_path)
		
		# We lock down the controller class to prevent unsafe modifications:
		klass.freeze
		
		# Create an instance of the controller:
		return klass.new
	else
		return nil
	end
end

#lookup_controller(path) ⇒ Object

Fetch the controller for the given relative path. May be cached.



68
69
70
71
72
 
# File 'lib/utopia/controller.rb', line 68

def lookup_controller(path)
	@controller_cache.fetch_or_store(path.to_s) do
		load_controller_file(path)
	end
end