Class: Settings::DBStore

Inherits:
ValueStore show all
Defined in:
lib/iron/settings/db_store.rb

Overview

Implements database-backed value storage for dynamic settings. This value store is appropriate for both class-level and instance-level settings storage. This store takes no special options on creation, however it is critical that the proper :reload option be set for your use-case.

For class-level settings, the proper option (and default) will often be to use a synchronization file by specifying :reload => ‘<some path>’ during initialization. This will cause the value store to touch the given file on saving changes, and reload values when the timestamp on the file is newer than the last reload.

For example, in Rails (with long-running, multi-instance operations), this will allow you to have your settings loaded once on load, then once per instance when changes are saved to the database.

For instance-level settings, the proper value is often :reload => false, as the values will be loaded on initilization of the instance, then thrown away with the instance. This will be ideal for Models in Rails, for example. If you have long-running instances that need reloads, you can use a shared timestamp as above, causing all instances to reload when any instance changes (feasible for a small number of instances or when settings do not change frequently), or you can set a timeout in seconds using :reload => <num seconds> to cause instances to reload after that time has elapsed.

Instance Method Summary collapse

Methods inherited from ValueStore

#get_value, #has_value?, #need_reload?, #read_only?, #reload_if_needed, #set_value

Constructor Details

#initialize(root, context, options = {}) ⇒ DBStore

Returns a new instance of DBStore.



24
25
26
27
28
29
30
31
32
 
# File 'lib/iron/settings/db_store.rb', line 24

def initialize(root, context, options = {})
  options = {
    :reload => false
  }.merge(options)
  @context = context

  # Let our base class at it
  super(root, options)
end

Instance Method Details

#load ⇒ Object 



34
35
36
37
38
39
40
41
 
# File 'lib/iron/settings/db_store.rb', line 34

def load
  super
  
  # Load up the values from DB, store in internal values hash by full key
  Settings::DBValue.for_context(@context).each do |val|
    @values[val.full_key] = val.value
  end
end

#save ⇒ Object 



43
44
45
46
47
48
49
50
51
52
53
 
# File 'lib/iron/settings/db_store.rb', line 43

def save
  # Clear any old settings
  Settings::DBValue.for_context(@context).delete_all
  
  # Create new settings
  @values.each_pair do |key, val|
    Settings::DBValue.create(context: @context, full_key: key, value: val)
  end
  
  super
end