Class: Sequel::Model::Associations::AssociationReflection

Inherits:
Hash
  • Object
show all
Includes:
Inflections
Defined in:
lib/sequel/model/associations.rb

Overview

AssociationReflection is a Hash subclass that keeps information on Sequel::Model associations. It provides methods to reduce internal code duplication. It should not be instantiated by the user.

Constant Summary

Constants included from Inflections

Inflections::CAMELIZE_CONVERT_REGEXP, Inflections::CAMELIZE_MODULE_REGEXP, Inflections::DASH, Inflections::DEMODULIZE_CONVERT_REGEXP, Inflections::EMPTY_STRING, Inflections::SLASH, Inflections::UNDERSCORE, Inflections::UNDERSCORE_CONVERT_REGEXP1, Inflections::UNDERSCORE_CONVERT_REGEXP2, Inflections::UNDERSCORE_CONVERT_REPLACE, Inflections::UNDERSCORE_MODULE_REGEXP, Inflections::VALID_CONSTANT_NAME_REGEXP

Instance Method Summary collapse

Methods included from Inflections

clear, irregular, plural, singular, uncountable

Methods inherited from Hash

#&, #case, #hstore, #pg_json, #sql_expr, #sql_negate, #sql_or, #|, #~

Instance Method Details

#_add_method ⇒ Object

Name symbol for the _add internal association method



21
22
23
 
# File 'lib/sequel/model/associations.rb', line 21

def _add_method
  :"_add_#{singularize(self[:name])}"
end

#_remove_all_method ⇒ Object

Name symbol for the _remove_all internal association method



26
27
28
 
# File 'lib/sequel/model/associations.rb', line 26

def _remove_all_method
  :"_remove_all_#{self[:name]}"
end

#_remove_method ⇒ Object

Name symbol for the _remove internal association method



31
32
33
 
# File 'lib/sequel/model/associations.rb', line 31

def _remove_method
  :"_remove_#{singularize(self[:name])}"
end

#_setter_method ⇒ Object

Name symbol for the _setter association method



36
37
38
 
# File 'lib/sequel/model/associations.rb', line 36

def _setter_method
  :"_#{self[:name]}="
end

#add_method ⇒ Object

Name symbol for the add association method



41
42
43
 
# File 'lib/sequel/model/associations.rb', line 41

def add_method
  :"add_#{singularize(self[:name])}"
end

#apply_dataset_changes(ds) ⇒ Object

Apply all non-instance specific changes to the given dataset and return it.



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

def apply_dataset_changes(ds)
  ds.extend(AssociationDatasetMethods)
  ds.association_reflection = self
  self[:extend].each{|m| ds.extend(m)}
  ds = ds.select(*select) if select
  if c = self[:conditions]
    ds = (c.is_a?(Array) && !Sequel.condition_specifier?(c)) ? ds.where(*c) : ds.where(c)
  end
  ds = ds.order(*self[:order]) if self[:order]
  ds = ds.limit(*self[:limit]) if self[:limit]
  ds = ds.limit(1) if !returns_array? && self[:key]
  ds = ds.eager(*self[:eager]) if self[:eager]
  ds = ds.distinct if self[:distinct]
  ds
end

#associated_class ⇒ Object

The class associated to the current model class via this association



51
52
53
 
# File 'lib/sequel/model/associations.rb', line 51

def associated_class
  cached_fetch(:class){constantize(self[:class_name])}
end

#associated_dataset ⇒ Object

The dataset associated via this association, with the non-instance specific changes already applied.



57
58
59
 
# File 'lib/sequel/model/associations.rb', line 57

def associated_dataset
  cached_fetch(:_dataset){apply_dataset_changes(associated_class.dataset.clone)}
end

#association_method ⇒ Object

Name symbol for association method, the same as the name of the association.



46
47
48
 
# File 'lib/sequel/model/associations.rb', line 46

def association_method
  self[:name]
end

#can_have_associated_objects?(obj) ⇒ Boolean

Whether this association can have associated objects, given the current object. Should be false if obj cannot have associated objects because the necessary key columns are NULL.



81
82
83
 
# File 'lib/sequel/model/associations.rb', line 81

def can_have_associated_objects?(obj)
  true
end

#dataset_method ⇒ Object

Name symbol for the dataset association method



86
87
88
 
# File 'lib/sequel/model/associations.rb', line 86

def dataset_method
  :"#{self[:name]}_dataset"
end

#dataset_need_primary_key? ⇒ Boolean

Whether the dataset needs a primary key to function, true by default.



91
92
93
 
# File 'lib/sequel/model/associations.rb', line 91

def dataset_need_primary_key?
  true
end

#eager_graph_lazy_dataset? ⇒ Boolean

Whether to eagerly graph a lazy dataset, true by default. If this is false, the association won't respect the :eager_graph option when loading the association for a single record.



135
136
137
 
# File 'lib/sequel/model/associations.rb', line 135

def eager_graph_lazy_dataset?
  true
end

#eager_limit_strategy ⇒ Object

The eager limit strategy to use for this dataset.



96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
 
# File 'lib/sequel/model/associations.rb', line 96

def eager_limit_strategy
  cached_fetch(:_eager_limit_strategy) do
    if self[:limit]
      case s = cached_fetch(:eager_limit_strategy){self[:model].default_eager_limit_strategy || :ruby}
      when true
        ds = associated_class.dataset
        if ds.supports_window_functions?
          :window_function
        else
          :ruby
        end
      else
        s
      end
    else
      nil
    end
  end
end

#eager_loader_key ⇒ Object

The key to use for the key hash when eager loading



117
118
119
 
# File 'lib/sequel/model/associations.rb', line 117

def eager_loader_key
  self[:eager_loader_key]
end

#eager_loading_predicate_key ⇒ Object

Alias of predicate_key, only for backwards compatibility.



128
129
130
 
# File 'lib/sequel/model/associations.rb', line 128

def eager_loading_predicate_key
  predicate_key
end

#eager_loading_use_associated_key? ⇒ Boolean

By default associations do not need to select a key in an associated table to eagerly load.



123
124
125
 
# File 'lib/sequel/model/associations.rb', line 123

def eager_loading_use_associated_key?
  false
end

#limit_and_offset ⇒ Object

The limit and offset for this association (returned as a two element array).



140
141
142
143
144
145
146
 
# File 'lib/sequel/model/associations.rb', line 140

def limit_and_offset
  if (v = self[:limit]).is_a?(Array)
    v
  else
    [v, nil]
  end
end

#need_associated_primary_key? ⇒ Boolean

Whether the associated object needs a primary key to be added/removed, false by default.



150
151
152
 
# File 'lib/sequel/model/associations.rb', line 150

def need_associated_primary_key?
  false
end

#predicate_keys ⇒ Object

The keys to use for loading of the regular dataset, as an array.



155
156
157
 
# File 'lib/sequel/model/associations.rb', line 155

def predicate_keys
  cached_fetch(:predicate_keys){Array(predicate_key)}
end

#qualify(table, col) ⇒ Object

Qualify col with the given table name. If col is an array of columns, return an array of qualified columns. Only qualifies Symbols and SQL::Identifier values, other values are not modified.



162
163
164
165
166
167
168
169
170
171
 
# File 'lib/sequel/model/associations.rb', line 162

def qualify(table, col)
  transform(col) do |k|
    case k
    when Symbol, SQL::Identifier
      SQL::QualifiedIdentifier.new(table, k)
    else
      Sequel::Qualifier.new(self[:model].dataset, table).transform(k)
    end
  end
end

#qualify_assoc(col) ⇒ Object

Qualify col with the associated model's table name.



174
175
176
 
# File 'lib/sequel/model/associations.rb', line 174

def qualify_assoc(col)
  qualify(associated_class.table_name, col)
end

#qualify_cur(col) ⇒ Object

Qualify col with the current model's table name.



179
180
181
 
# File 'lib/sequel/model/associations.rb', line 179

def qualify_cur(col)
  qualify(self[:model].table_name, col)
end

#reciprocal ⇒ Object

Returns the reciprocal association variable, if one exists. The reciprocal association is the association in the associated class that is the opposite of the current association. For example, Album.many_to_one :artist and Artist.one_to_many :albums are reciprocal associations. This information is to populate reciprocal associations. For example, when you do this_artist.add_album(album) it sets album.artist to this_artist.



189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
 
# File 'lib/sequel/model/associations.rb', line 189

def reciprocal
  cached_fetch(:reciprocal) do
    possible_recips = []
    fallback_recips = []

    associated_class.all_association_reflections.each do |assoc_reflect|
      if reciprocal_association?(assoc_reflect)
        if deprecated_reciprocal_association?(assoc_reflect)
          fallback_recips << assoc_reflect
        else
          possible_recips << assoc_reflect
        end
      end
    end

    Sequel::Deprecation.deprecate("Multiple reciprocal association candidates found for #{self[:name]} association (#{possible_recips.map{|r| r[:name]}.join(', ')}).  Choosing the first candidate is", "Please explicitly specify the reciprocal option for the #{self[:name]} association") if possible_recips.size >= 2
    if possible_recips.empty? && !fallback_recips.empty?
      possible_recips = fallback_recips
      Sequel::Deprecation.deprecate("All reciprocal association candidates found for #{self[:name]} association have conditions, blocks, or differing primary keys (#{possible_recips.map{|r| r[:name]}.join(', ')}).  Automatic choosing of an reciprocal association with conditions or blocks is", "Please explicitly specify the reciprocal option for the #{self[:name]} association")
    end

    unless possible_recips.empty?
      cached_set(:reciprocal_type, possible_recips.first[:type]) if reciprocal_type.is_a?(Array)
      possible_recips.first[:name]
    end
  end
end

#reciprocal_array? ⇒ Boolean

Whether the reciprocal of this association returns an array of objects instead of a single object, true by default.



219
220
221
 
# File 'lib/sequel/model/associations.rb', line 219

def reciprocal_array?
  true
end

#remove_all_method ⇒ Object

Name symbol for the remove_all_ association method



224
225
226
 
# File 'lib/sequel/model/associations.rb', line 224

def remove_all_method
  :"remove_all_#{self[:name]}"
end

#remove_before_destroy? ⇒ Boolean

Whether associated objects need to be removed from the association before being destroyed in order to preserve referential integrity.



230
231
232
 
# File 'lib/sequel/model/associations.rb', line 230

def remove_before_destroy?
  true
end

#remove_method ⇒ Object

Name symbol for the remove_ association method



235
236
237
 
# File 'lib/sequel/model/associations.rb', line 235

def remove_method
  :"remove_#{singularize(self[:name])}"
end

#remove_should_check_existing? ⇒ Boolean

Whether to check that an object to be disassociated is already associated to this object, false by default.



240
241
242
 
# File 'lib/sequel/model/associations.rb', line 240

def remove_should_check_existing?
  false
end

#returns_array? ⇒ Boolean

Whether this association returns an array of objects instead of a single object, true by default.



246
247
248
 
# File 'lib/sequel/model/associations.rb', line 246

def returns_array?
  true
end

#select ⇒ Object

The columns to select when loading the association.



251
252
253
 
# File 'lib/sequel/model/associations.rb', line 251

def select
  self[:select]
end

#set_reciprocal_to_self? ⇒ Boolean

Whether to set the reciprocal association to self when loading associated records, false by default.



257
258
259
 
# File 'lib/sequel/model/associations.rb', line 257

def set_reciprocal_to_self?
  false
end

#setter_method ⇒ Object

Name symbol for the setter association method



262
263
264
 
# File 'lib/sequel/model/associations.rb', line 262

def setter_method
  :"#{self[:name]}="
end