Class: ActiveSnapshot::Snapshot

Inherits:
ActiveRecord::Base
  • Object
show all
Defined in:
lib/active_snapshot/models/snapshot.rb

Instance Method Summary collapse

Instance Method Details

#build_snapshot_item(instance, child_group_name: nil) ⇒ Object 



48
49
50
51
52
53
54
55
 
# File 'lib/active_snapshot/models/snapshot.rb', line 48

def build_snapshot_item(instance, child_group_name: nil)
  self.snapshot_items.new({
    object: instance.attributes,
    item_id: instance.id,
    item_type: instance.class.name,
    child_group_name: child_group_name,
  })
end

#fetch_reified_items ⇒ Object 



99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
 
# File 'lib/active_snapshot/models/snapshot.rb', line 99

def fetch_reified_items
  reified_children_hash = {}.with_indifferent_access

  reified_parent = nil

  snapshot_items.each do |si|
    reified_item = si.item_type.constantize.new(si.object)

    reified_item.readonly!

    key = si.child_group_name

    if key
      reified_children_hash[key] ||= []

      reified_children_hash[key] << reified_item

    elsif self.item_id == si.item_id && (self.item_type == si.item_type || si.item_type.constantize.new.is_a?(self.item_type.constantize))
      reified_parent = reified_item
    end
  end

  return [reified_parent, reified_children_hash]
end

#metadata ⇒ Object 



18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
 
# File 'lib/active_snapshot/models/snapshot.rb', line 18

def metadata
  return @metadata if @metadata

  if ActiveSnapshot.config.storage_method_json?
    @metadata = JSON.parse(self[:metadata])
  elsif ActiveSnapshot.config.storage_method_yaml?
    yaml_method = "unsafe_load"

    if !YAML.respond_to?("unsafe_load")
      yaml_method = "load"
    end

    @metadata = YAML.send(yaml_method, self[:metadata])
  elsif ActiveSnapshot.config.storage_method_native_json?
    @metadata = self[:metadata]
  end
end

#metadata=(h) ⇒ Object 



36
37
38
39
40
41
42
43
44
45
46
 
# File 'lib/active_snapshot/models/snapshot.rb', line 36

def metadata=(h)
  @metadata = nil

  if ActiveSnapshot.config.storage_method_json?
    self[:metadata] = h.to_json
  elsif ActiveSnapshot.config.storage_method_yaml?
    self[:metadata] = YAML.dump(h)
  elsif ActiveSnapshot.config.storage_method_native_json?
    self[:metadata] = h
  end
end

#restore! ⇒ Object 



57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
 
# File 'lib/active_snapshot/models/snapshot.rb', line 57

def restore!
  ActiveRecord::Base.transaction do
    ### Cache the child snapshots in a variable for re-use
    cached_snapshot_items = snapshot_items.includes(:item)

    existing_snapshot_children = item ? item.children_to_snapshot : []

    if existing_snapshot_children.any?
      children_to_keep = Set.new

      cached_snapshot_items.each do |snapshot_item|
        key = "#{snapshot_item.item_type} #{snapshot_item.item_id}"

        children_to_keep << key
      end

      ### Destroy or Detach Items not included in this Snapshot's Items
      ### We do this first in case you later decide to validate children in ItemSnapshot#restore_item! method
      existing_snapshot_children.each do |child_group_name, h|
        delete_method = h[:delete_method] || ->(child_record){ child_record.destroy! }

        h[:records].each do |child_record|
          child_record_id = child_record.send(child_record.class.send(:primary_key))

          key = "#{child_record.class.name} #{child_record_id}"

          if children_to_keep.exclude?(key)
            delete_method.call(child_record)
          end
        end
      end
    end

    ### Create or Update Items from Snapshot Items
    cached_snapshot_items.each do |snapshot_item|
      snapshot_item.restore_item!
    end
  end

  return true
end