Class: DiasporaFederation::Callbacks

Inherits:
Object
  • Object
show all
Defined in:
lib/diaspora_federation/callbacks.rb

Overview

Callbacks are used to communicate with the application. They are called to fetch data and after data is received.

Instance Method Summary collapse

Constructor Details

#initialize(events) ⇒ Callbacks

Initializes a new Callbacks object with the event-keys that need to be defined

Examples:

Callbacks.new %i(
  some_event
  another_event
)

Parameters:

  • events (Hash) —

    event keys



16
17
18
19
 
# File 'lib/diaspora_federation/callbacks.rb', line 16

def initialize(events)
  @events   = events
  @handlers = {}
end

Instance Method Details

#definition_complete? ⇒ Boolean

Checks if all callbacks are defined

Returns:

  • (Boolean) 


54
55
56
 
# File 'lib/diaspora_federation/callbacks.rb', line 54

def definition_complete?
  missing_handlers.empty?
end

#missing_handlers ⇒ Hash

Returns all undefined callbacks

Returns:

  • (Hash) —

    callback keys



60
61
62
 
# File 'lib/diaspora_federation/callbacks.rb', line 60

def missing_handlers
  @events - @handlers.keys
end

#on(event, &callback) ⇒ Object

Defines a callback

Examples:

callbacks.on :some_event do |arg1|
  # do something
end

Parameters:

  • event (Symbol) —

    the event key

  • callback (Proc) —

    the callback block

Raises:

  • (ArgumentError) —

    if the event key is undefined or has already a handler



31
32
33
34
35
36
 
# File 'lib/diaspora_federation/callbacks.rb', line 31

def on(event, &callback)
  raise ArgumentError, "Undefined event #{event}" unless @events.include? event
  raise ArgumentError, "Already defined event #{event}" if @handlers.has_key? event

  @handlers[event] = callback
end

#trigger(event, *args) ⇒ Object

Triggers a callback

Examples:

callbacks.trigger :some_event, "foo"

Parameters:

  • event (Symbol) —

    the event key

Returns:

  • (Object) —

    the return-value of the callback

Raises:

  • (ArgumentError) —

    if the event key is undefined



46
47
48
49
50
 
# File 'lib/diaspora_federation/callbacks.rb', line 46

def trigger(event, *args)
  raise ArgumentError, "Undefined event #{event}" unless @events.include? event

  @handlers[event].call(*args)
end