Class: CanCan::ModelAdapters::ActiveRecordAdapter

Inherits:
AbstractAdapter show all
Defined in:
lib/cancan/model_adapters/active_record_adapter.rb

Direct Known Subclasses

ActiveRecord4Adapter

Instance Attribute Summary collapse

Attributes inherited from AbstractAdapter

#model_class

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from AbstractAdapter

adapter_class, find, for_class?, inherited, matches_condition?, matches_conditions_hash?, override_condition_matching?, override_conditions_hash_matching?

Constructor Details

#initialize(model_class, rules) ⇒ ActiveRecordAdapter

Returns a new instance of ActiveRecordAdapter.


16
17
18
19
20
21
# File 'lib/cancan/model_adapters/active_record_adapter.rb', line 16

def initialize(model_class, rules)
  super
  @compressed_rules = RulesCompressor.new(@rules.reverse).rules_collapsed.reverse
  StiNormalizer.normalize(@compressed_rules)
  ConditionsNormalizer.normalize(model_class, @compressed_rules)
end

Instance Attribute Details

#compressed_rulesObject (readonly)

Returns the value of attribute compressed_rules.


14
15
16
# File 'lib/cancan/model_adapters/active_record_adapter.rb', line 14

def compressed_rules
  @compressed_rules
end

Class Method Details

.nested_subject_matches_conditions?(parent, child, all_conditions) ⇒ Boolean

parent_id condition can be an array of integer or one integer, we check the parent against this

Returns:

  • (Boolean)

31
32
33
34
35
36
37
# File 'lib/cancan/model_adapters/active_record_adapter.rb', line 31

def nested_subject_matches_conditions?(parent, child, all_conditions)
  id_condition = parent_child_conditions(parent, child, all_conditions)
  return id_condition.include?(parent.id) if id_condition.is_a? Array
  return id_condition == parent.id if id_condition.is_a? Integer

  false
end

.override_nested_subject_conditions_matching?(parent, child, all_conditions) ⇒ Boolean

When belongs_to parent_id is a condition for a model, we want to check the parent when testing ability for a hash => model

Returns:

  • (Boolean)

26
27
28
# File 'lib/cancan/model_adapters/active_record_adapter.rb', line 26

def override_nested_subject_conditions_matching?(parent, child, all_conditions)
  parent_child_conditions(parent, child, all_conditions).present?
end

.parent_child_conditions(parent, child, all_conditions) ⇒ Object


39
40
41
42
43
44
45
# File 'lib/cancan/model_adapters/active_record_adapter.rb', line 39

def parent_child_conditions(parent, child, all_conditions)
  child_class = child.is_a?(Class) ? child : child.class
  foreign_key = child_class.reflect_on_all_associations(:belongs_to).find do |association|
                  association.klass == parent.class
                end&.foreign_key&.to_sym
  foreign_key.nil? ? nil : all_conditions[foreign_key]
end

.version_greater_or_equal?(version) ⇒ Boolean

Returns:

  • (Boolean)

6
7
8
# File 'lib/cancan/model_adapters/active_record_adapter.rb', line 6

def self.version_greater_or_equal?(version)
  Gem::Version.new(ActiveRecord.version).release >= Gem::Version.new(version)
end

.version_lower?(version) ⇒ Boolean

Returns:

  • (Boolean)

10
11
12
# File 'lib/cancan/model_adapters/active_record_adapter.rb', line 10

def self.version_lower?(version)
  Gem::Version.new(ActiveRecord.version).release < Gem::Version.new(version)
end

Instance Method Details

#build_relation(*where_conditions) ⇒ Object


89
90
91
92
93
94
95
# File 'lib/cancan/model_adapters/active_record_adapter.rb', line 89

def build_relation(*where_conditions)
  relation = @model_class.where(*where_conditions)
  return relation unless joins.present?

  # subclasses must implement `build_joins_relation`
  build_joins_relation(relation, *where_conditions)
end

#conditionsObject

Returns conditions intended to be used inside a database query. Normally you will not call this method directly, but instead go through ModelAdditions#accessible_by.

If there is only one “can” definition, a hash of conditions will be returned matching the one defined.

can :manage, User, :id => 1
query(:manage, User).conditions # => { :id => 1 }

If there are multiple “can” definitions, a SQL string will be returned to handle complex cases.

can :manage, User, :id => 1
can :manage, User, :manager_id => 1
cannot :manage, User, :self_managed => true
query(:manage, User).conditions # => "not (self_managed = 't') AND ((manager_id = 1) OR (id = 1))"

63
64
65
66
67
68
69
70
71
# File 'lib/cancan/model_adapters/active_record_adapter.rb', line 63

def conditions
  conditions_extractor = ConditionsExtractor.new(@model_class)
  if @compressed_rules.size == 1 && @compressed_rules.first.base_behavior
    # Return the conditions directly if there's just one definition
    conditions_extractor.tableize_conditions(@compressed_rules.first.conditions).dup
  else
    extract_multiple_conditions(conditions_extractor, @compressed_rules)
  end
end

#database_recordsObject


79
80
81
82
83
84
85
86
87
# File 'lib/cancan/model_adapters/active_record_adapter.rb', line 79

def database_records
  if override_scope
    @model_class.where(nil).merge(override_scope)
  elsif @model_class.respond_to?(:where) && @model_class.respond_to?(:joins)
    build_relation(conditions)
  else
    @model_class.all(conditions: conditions, joins: joins)
  end
end

#extract_multiple_conditions(conditions_extractor, rules) ⇒ Object


73
74
75
76
77
# File 'lib/cancan/model_adapters/active_record_adapter.rb', line 73

def extract_multiple_conditions(conditions_extractor, rules)
  rules.reverse.inject(false_sql) do |sql, rule|
    merge_conditions(sql, conditions_extractor.tableize_conditions(rule.conditions).dup, rule.base_behavior)
  end
end

#joinsObject

Returns the associations used in conditions for the :joins option of a search. See ModelAdditions#accessible_by


99
100
101
102
103
104
105
# File 'lib/cancan/model_adapters/active_record_adapter.rb', line 99

def joins
  joins_hash = {}
  @compressed_rules.reverse_each do |rule|
    deep_merge(joins_hash, rule.associations_hash)
  end
  deep_clean(joins_hash) unless joins_hash.empty?
end