Class: Capistrano::ConsulKvLock::Latch

Inherits:
Object
  • Object
show all
Defined in:
lib/capistrano/consul_kv_lock/latch.rb

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(consul_url, options = {}) ⇒ Latch

Returns a new instance of Latch.



34
35
36
37
38
 
# File 'lib/capistrano/consul_kv_lock/latch.rb', line 34

def initialize(consul_url, options={})
  Diplomat.configuration.url = consul_url
  @lock_key = options[:consul_lock_key] || 'deployment/locked'
  @session_id = nil
end

Instance Attribute Details

#lock_key ⇒ Object (readonly)

Returns the value of attribute lock_key.



39
40
41
 
# File 'lib/capistrano/consul_kv_lock/latch.rb', line 39

def lock_key
  @lock_key
end

Class Method Details

.instance ⇒ Object 



26
27
28
 
# File 'lib/capistrano/consul_kv_lock/latch.rb', line 26

def self.instance
  @_instance
end

.logger ⇒ Object 



30
31
32
 
# File 'lib/capistrano/consul_kv_lock/latch.rb', line 30

def self.logger
  @_logger ||= SSHKittyLogger.new
end

.set_instance(consul_url, options = {}) ⇒ Object 



20
21
22
23
24
 
# File 'lib/capistrano/consul_kv_lock/latch.rb', line 20

def self.set_instance(consul_url, options={})
  @_instance ||= new(consul_url, options)
  logger.debug "Registered latch instance: #{@_instance.inspect}"
  @_instance
end

Instance Method Details

#create_session ⇒ Object 



63
64
65
66
 
# File 'lib/capistrano/consul_kv_lock/latch.rb', line 63

def create_session
  logger.debug "Session request: #{session_request.inspect}"
  @session_id = Diplomat::Session.create(session_request)
end

#delete_session ⇒ Object 



68
69
70
71
72
73
 
# File 'lib/capistrano/consul_kv_lock/latch.rb', line 68

def delete_session
  with_session {
    Diplomat::Session.destroy(@session_id)
  }
  @session_id = nil
end

#lock ⇒ Object 



75
76
77
 
# File 'lib/capistrano/consul_kv_lock/latch.rb', line 75

def lock
  with_session { Diplomat::Lock.acquire(lock_key, @session_id, "true") }
end

#locked? ⇒ Boolean

Returns:

  • (Boolean) 


52
53
54
55
56
57
58
59
60
61
 
# File 'lib/capistrano/consul_kv_lock/latch.rb', line 52

def locked?
  !!(Diplomat::Kv.get(lock_key) =~ /\A(t(rue)?|1|y(es)?)\z/)
rescue => e
  # in case of 404
  if e.message.include?('404')
    return false
  else
    raise e
  end
end

#logger ⇒ Object 



41
42
43
 
# File 'lib/capistrano/consul_kv_lock/latch.rb', line 41

def logger
  self.class.logger
end

#session_request ⇒ Object 



45
46
47
48
49
50
 
# File 'lib/capistrano/consul_kv_lock/latch.rb', line 45

def session_request
  {
    "LockDelay" => 15,
    "Name" => "lock-for-#{lock_key.tr("/", "-")}",
  }
end

#unlock ⇒ Object 



79
80
81
 
# File 'lib/capistrano/consul_kv_lock/latch.rb', line 79

def unlock
  with_session { Diplomat::Lock.release(lock_key, @session_id) }
end