Class: Deltacloud::DSL::Task

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

Instance Attribute Summary (collapse)

Instance Method Summary (collapse)

Constructor Details

- (Task) initialize(name, &block)

A new instance of Task



11
12
13
14
15
16
 
# File 'lib/task.rb', line 11

def initialize(name, &block)
  @name = name
  @state_machine = {}
  @log = Logger.new(STDERR)
  define &block
end

Dynamic Method Handling

This class handles dynamic methods through the method_missing method

- (Object) method_missing(name, *args)

Declare a set of methods dynamically:

find_instances_by_ => returns InstanceDefinition objects that

match the value of attribute provided in method name

[driver]_instances => return InstanceDefinition objects that correspond

to given driver

[driver]_instance => return Instance object that match with name

eg. mock_instance 'test-mock-1' will find this
instance.

instances_ => return Instance objects with corresponding state



62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
 
# File 'lib/task.rb', line 62

def method_missing(name, *args)
  if name.to_s =~ /^find_instances_by_([\w_]+)$/
    @instances.select { |i| i.configuration.respond_to?($1.intern) && args.include?(i.configuration.send($1.intern)) }
  elsif name.to_s =~ /^(\w+)_instances$/
    find_instances_by_driver($1.intern)
  elsif name.to_s =~ /^(\w+)_instance$/
    inst = find_instances_by_driver($1.intern).map { |instances| instances.find { |i| args.include?(i.name) } }.flatten.compact.first
    yield inst if block_given?
    inst
  elsif name.to_s =~ /^instances_(\w+)\?$/
    @instances.any? { |d| d.map { |i| (i.update! rescue true) && i.instance_state == $1.intern }.include? true }
  else
    super
  end
end

Instance Attribute Details

- (Object) log (readonly)

Returns the value of attribute log



9
10
11
 
# File 'lib/task.rb', line 9

def log
  @log
end

- (Object) name (readonly)

Returns the value of attribute name



9
10
11
 
# File 'lib/task.rb', line 9

def name
  @name
end

- (Object) state_machine (readonly)

Returns the value of attribute state_machine



9
10
11
 
# File 'lib/task.rb', line 9

def state_machine
  @state_machine
end

Instance Method Details

- (Object) define(&block) 



18
19
20
 
# File 'lib/task.rb', line 18

def define(&block)
  instance_eval(&block) if block_given?
end

- (Object) instances(configuration = {}, &block)

Configure group of instances that would be launched using specified configuration.

Configuration:

:driver - Deltacloud API driver to use (default: mock) :provider - API_PROVIDER (eg. URL to RHEV-M API) :username - API key (default: mockuser) :password - API secret (default: mockpassword) :url - Deltacloud API url (default: localhost:3001/api)

The block should define single instances:

instances(:driver => :ec2, :username => API_KEY, :password => API_SECRET) do

instance 'instance-1' do
  # instance configuration here
end

end



41
42
43
44
45
46
 
# File 'lib/task.rb', line 41

def instances(configuration={}, &block)
  return find_instances_by_driver(configuration) if configuration.kind_of? Symbol
  @instances ||= []
  @instances << Deltacloud::DSL::Instances(configuration, &block) if block_given?
  @instances
end

- (Object) on(state, &block)

Handler for callback definition:

on(:running) do end

on(:instance_started) do |instance| end



122
123
124
 
# File 'lib/task.rb', line 122

def on(state, &block)
  @state_machine[state] = block if block_given?
end

- (Object) perform(s, item = nil)

Syntax sugar for performing callbacks



134
135
136
137
 
# File 'lib/task.rb', line 134

def perform(s, item=nil)
  return unless @state_machine.keys.include?(s)
  state(s).call(item)
end

- (Object) start!

Start executing given task.

This method will try to start all instances defined for all drivers. Then it will wait for instances to become running.

Various callback can be provided for different state:

on(:running) callback is triggered when all instances are running on(:instance_started) callback is triggered for every instance when become running



88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
 
# File 'lib/task.rb', line 88

def start!
  task = self
  EventMachine::run do
    inst_arr = []
    task.instances.each do |definition|
      inst_arr += definition.instances
      definition.instances.each do |instance|
        Thread.new do
          begin
            instance.create(definition).wait_for_running!
            perform(:instance_started, instance)
            log.info "Instance #{instance.name}[#{definition.configuration.driver}] successfully started."
          rescue => e
            log.error "ERROR: #{e.message}"
          ensure
            inst_arr.delete(instance)
          end
        end
      end
    end
    until inst_arr.empty?; end
    perform(:running)
    EM.stop
  end
end

- (Object) state(state)

Syntax sugar for @state_machine callbacks



128
129
130
 
# File 'lib/task.rb', line 128

def state(state)
  @state_machine[state]
end