Module: Sequel::Model::ClassMethods

Included in:
Sequel::Model
Defined in:
lib/sequel/model/base.rb

Overview

Class methods for Sequel::Model that implement basic model functionality.

  • All of the method names in Model::DATASET_METHODS have class methods created that call the Model’s dataset with the method of the same name with the given arguments.

Instance Attribute Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#allowed_columns ⇒ Object (readonly)

Which columns should be the only columns allowed in a call to a mass assignment method (e.g. set) (default: not set, so all columns not otherwise restricted are allowed).



13
14
15
 
# File 'lib/sequel/model/base.rb', line 13

def allowed_columns
  @allowed_columns
end

#dataset_method_modules ⇒ Object (readonly)

Array of modules that extend this model’s dataset. Stored so that if the model’s dataset is changed, it will be extended with all of these modules.



28
29
30
 
# File 'lib/sequel/model/base.rb', line 28

def dataset_method_modules
  @dataset_method_modules
end

#default_set_fields_options ⇒ Object

The default options to use for Model#set_fields. These are merged with the options given to set_fields.



32
33
34
 
# File 'lib/sequel/model/base.rb', line 32

def default_set_fields_options
  @default_set_fields_options
end

#fast_instance_delete_sql ⇒ Object (readonly)

SQL string fragment used for faster DELETE statement creation when deleting/destroying model instances, or nil if the optimization should not be used. For internal use only.



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

def fast_instance_delete_sql
  @fast_instance_delete_sql
end

#instance_dataset ⇒ Object (readonly)

The dataset that instance datasets (#this) are based on. Generally a naked version of the model’s dataset limited to one row. For internal use only.



40
41
42
 
# File 'lib/sequel/model/base.rb', line 40

def instance_dataset
  @instance_dataset
end

#plugins ⇒ Object (readonly)

Array of plugin modules loaded by this class

Sequel::Model.plugins
# => [Sequel::Model, Sequel::Model::Associations]



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

def plugins
  @plugins
end

#primary_key ⇒ Object (readonly)

The primary key for the class. Sequel can determine this automatically for many databases, but not all, so you may need to set it manually. If not determined automatically, the default is :id.



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

def primary_key
  @primary_key
end

#raise_on_save_failure ⇒ Object

Whether to raise an error instead of returning nil on a failure to save/create/save_changes/etc due to a validation failure or a before_* hook returning false.



56
57
58
 
# File 'lib/sequel/model/base.rb', line 56

def raise_on_save_failure
  @raise_on_save_failure
end

#raise_on_typecast_failure ⇒ Object

Whether to raise an error when unable to typecast data for a column (default: true). This should be set to false if you want to use validations to display nice error messages to the user (e.g. most web applications). You can use the validates_schema_types validation (from the validation_helpers plugin) in connection with this setting to check for typecast failures during validation.



64
65
66
 
# File 'lib/sequel/model/base.rb', line 64

def raise_on_typecast_failure
  @raise_on_typecast_failure
end

#require_modification ⇒ Object

Whether to raise an error if an UPDATE or DELETE query related to a model instance does not modify exactly 1 row. If set to false, Sequel will not check the number of rows modified (default: true).



69
70
71
 
# File 'lib/sequel/model/base.rb', line 69

def require_modification
  @require_modification
end

#simple_pk ⇒ Object

Should be the literal primary key column name if this Model’s table has a simple primary key, or nil if the model has a compound primary key or no primary key.



82
83
84
 
# File 'lib/sequel/model/base.rb', line 82

def simple_pk
  @simple_pk
end

#simple_table ⇒ Object

Should be the literal table name if this Model’s dataset is a simple table (no select, order, join, etc.), or nil otherwise. This and simple_pk are used for an optimization in Model.[].



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

def simple_table
  @simple_table
end

#strict_param_setting ⇒ Object

Whether new/set/update and their variants should raise an error if an invalid key is used. A key is invalid if no setter method exists for that key or the access to the setter method is restricted (e.g. due to it being a primary key field). If set to false, silently skip any key where the setter method doesn’t exist or access to it is restricted.



93
94
95
 
# File 'lib/sequel/model/base.rb', line 93

def strict_param_setting
  @strict_param_setting
end

#typecast_empty_string_to_nil ⇒ Object

Whether to typecast the empty string (”) to nil for columns that are not string or blob. In most cases the empty string would be the way to specify a NULL SQL value in string form (nil.to_s == ”), and an empty string would not usually be typecast correctly for other types, so the default is true.



100
101
102
 
# File 'lib/sequel/model/base.rb', line 100

def typecast_empty_string_to_nil
  @typecast_empty_string_to_nil
end

#typecast_on_assignment ⇒ Object

Whether to typecast attribute values on assignment (default: true). If set to false, no typecasting is done, so it will be left up to the database to typecast the value correctly.



105
106
107
 
# File 'lib/sequel/model/base.rb', line 105

def typecast_on_assignment
  @typecast_on_assignment
end

#use_after_commit_rollback ⇒ Object

Whether to enable the after_commit and after_rollback hooks when saving/destroying instances. On by default, can be turned off for performance reasons or when using prepared transactions (which aren’t compatible with after commit/rollback).



110
111
112
 
# File 'lib/sequel/model/base.rb', line 110

def use_after_commit_rollback
  @use_after_commit_rollback
end

#use_transactions ⇒ Object

Whether to use a transaction by default when saving/deleting records (default: true). If you are sending database queries in before_* or after_* hooks, you shouldn’t change the default setting without a good reason.



115
116
117
 
# File 'lib/sequel/model/base.rb', line 115

def use_transactions
  @use_transactions
end

Instance Method Details

#[](*args) ⇒ Object

Returns the first record from the database matching the conditions. If a hash is given, it is used as the conditions. If another object is given, it finds the first record whose primary key(s) match the given argument(s). If no object is returned by the dataset, returns nil.

Artist[1] # SELECT * FROM artists WHERE id = 1
# => #<Artist {:id=>1, ...}>

Artist[:name=>'Bob'] # SELECT * FROM artists WHERE (name = 'Bob') LIMIT 1
# => #<Artist {:name=>'Bob', ...}>



127
128
129
130
 
# File 'lib/sequel/model/base.rb', line 127

def [](*args)
  args = args.first if args.size <= 1
  args.is_a?(Hash) ? dataset[args] : (primary_key_lookup(args) unless args.nil?)
end

#_restricted_columns ⇒ Object 



76
77
78
 
# File 'lib/sequel/model/base.rb', line 76

def _restricted_columns
  @restricted_columns
end

#cache_anonymous_models ⇒ Object

REMOVE40



16
17
18
19
 
# File 'lib/sequel/model/base.rb', line 16

def cache_anonymous_models
  Sequel::Deprecation.deprecate('Model.cache_anonymous_models', 'Please switch to Sequel.cache_anonymous_models')
  Sequel.cache_anonymous_models
end

#cache_anonymous_models=(v) ⇒ Object 



20
21
22
23
 
# File 'lib/sequel/model/base.rb', line 20

def cache_anonymous_models=(v)
  Sequel::Deprecation.deprecate('Model.cache_anonymous_models=', 'Please switch to Sequel.cache_anonymous_models=')
  Sequel.cache_anonymous_models = v
end

#call(values) ⇒ Object

Initializes a model instance as an existing record. This constructor is used by Sequel to initialize model instances when fetching records. Requires that values be a hash where all keys are symbols. It probably should not be used by external code.



136
137
138
139
140
141
 
# File 'lib/sequel/model/base.rb', line 136

def call(values)
  o = allocate
  o.set_values(values)
  o.after_initialize
  o
end

#clear_setter_methods_cache ⇒ Object

Clear the setter_methods cache



144
145
146
 
# File 'lib/sequel/model/base.rb', line 144

def clear_setter_methods_cache
  @setter_methods = nil
end

#columns ⇒ Object

Returns the columns in the result set in their original order. Generally, this will use the columns determined via the database schema, but in certain cases (e.g. models that are based on a joined dataset) it will use Dataset#columns to find the columns.

Artist.columns
# => [:id, :name]



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

def columns
  @columns || set_columns(dataset.naked.columns)
end

#create(values = {}, &block) ⇒ Object

Creates instance using new with the given values and block, and saves it.

Artist.create(:name=>'Bob')
# INSERT INTO artists (name) VALUES ('Bob')

Artist.create do |a|
  a.name = 'Jim'
end # INSERT INTO artists (name) VALUES ('Jim')



167
168
169
 
# File 'lib/sequel/model/base.rb', line 167

def create(values = {}, &block)
  new(values, &block).save
end

#dataset ⇒ Object

Returns the dataset associated with the Model class. Raises an Error if there is no associated dataset for this class. In most cases, you don’t need to call this directly, as Model proxies many dataset methods to the underlying dataset.

Artist.dataset.all # SELECT * FROM artists



177
178
179
 
# File 'lib/sequel/model/base.rb', line 177

def dataset
  @dataset || raise(Error, "No dataset associated with #{self}")
end

#dataset=(ds) ⇒ Object

Alias of set_dataset



182
183
184
 
# File 'lib/sequel/model/base.rb', line 182

def dataset=(ds)
  set_dataset(ds)
end

#dataset_module(mod = nil) ⇒ Object

Extend the dataset with a module, similar to adding a plugin with the methods defined in DatasetMethods. This is the recommended way to add methods to model datasets.

If an argument, it should be a module, and is used to extend the underlying dataset. Otherwise an anonymous module is created, and if a block is given, it is module_evaled, allowing you do define dataset methods directly using the standard ruby def syntax. Returns the module given or the anonymous module created.

# Usage with existing module
Artist.dataset_module Sequel::ColumnsIntrospection

# Usage with anonymous module
Artist.dataset_module do
  def foo
    :bar
  end
end
Artist.dataset.foo
# => :bar
Artist.foo
# => :bar

Any anonymous modules created are actually instances of Sequel::Model::DatasetModule (a Module subclass), which allows you to call the subset method on them:

Artist.dataset_module do
  subset :released, Sequel.identifier(release_date) > Sequel::CURRENT_DATE
end

Any public methods in the dataset module will have class methods created that call the method on the dataset, assuming that the class method is not already defined.



220
221
222
223
224
225
226
227
228
229
230
231
 
# File 'lib/sequel/model/base.rb', line 220

def dataset_module(mod = nil)
  if mod
    raise Error, "can't provide both argument and block to Model.dataset_module" if block_given?
    dataset_extend(mod)
    mod
  else
    @dataset_module ||= DatasetModule.new(self)
    @dataset_module.module_eval(&Proc.new) if block_given?
    dataset_extend(@dataset_module)
    @dataset_module
  end
end

#db ⇒ Object

Returns the database associated with the Model class. If this model doesn’t have a database associated with it, assumes the superclass’s database, or the first object in Sequel::DATABASES. If no Sequel::Database object has been created, raises an error.

Artist.db.transaction do # BEGIN
  Artist.create(:name=>'Bob')
  # INSERT INTO artists (name) VALUES ('Bob')
end # COMMIT

Raises:



243
244
245
246
247
248
 
# File 'lib/sequel/model/base.rb', line 243

def db
  return @db if @db
  @db = self == Model ? Sequel.synchronize{DATABASES.first} : superclass.db
  raise(Error, "No database associated with #{self}: have you called Sequel.connect or #{self}.db= ?") unless @db
  @db
end

#db=(db) ⇒ Object

Sets the database associated with the Model class. If the model has an associated dataset, sets the model’s dataset to a dataset on the new database with the same options used by the current dataset. This can be used directly on Sequel::Model to set the default database to be used by subclasses, or to override the database used for specific models:

Sequel::Model.db = DB1
Artist.db = DB2

Note that you should not use this to change the model’s database at runtime. If you have that need, you should look into Sequel’s sharding support.



264
265
266
267
 
# File 'lib/sequel/model/base.rb', line 264

def db=(db)
  @db = db
  set_dataset(db.dataset.clone(@dataset.opts)) if @dataset
end

#db_schema ⇒ Object

Returns the cached schema information if available or gets it from the database. This is a hash where keys are column symbols and values are hashes of information related to the column. See Database#schema.

Artist.db_schema
# {:id=>{:type=>:integer, :primary_key=>true, ...},
#  :name=>{:type=>:string, :primary_key=>false, ...}}



277
278
279
 
# File 'lib/sequel/model/base.rb', line 277

def db_schema
  @db_schema ||= get_db_schema
end

#def_column_alias(meth, column) ⇒ Object

Create a column alias, where the column methods have one name, but the underlying storage uses a different name.



283
284
285
286
287
288
289
 
# File 'lib/sequel/model/base.rb', line 283

def def_column_alias(meth, column)
  clear_setter_methods_cache
  overridable_methods_module.module_eval do
    define_method(meth){self[column]}
    define_method("#{meth}="){|v| self[column] = v}
  end
end

#def_dataset_method(*args, &block) ⇒ Object

If a block is given, define a method on the dataset (if the model currently has an dataset) with the given argument name using the given block. Also define a class method on the model that calls the dataset method. Stores the method name and block so that it can be reapplied if the model’s dataset changes.

If a block is not given, just define a class method on the model for each argument that calls the dataset method of the same argument name.

It is recommended that you define methods inside a block passed to #dataset_module instead of using this method, as #dataset_module allows you to use normal ruby def syntax.

# Add new dataset method and class method that calls it
Artist.def_dataset_method(:by_name){order(:name)}
Artist.filter(:name.like('A%')).by_name
Artist.by_name.filter(:name.like('A%'))

# Just add a class method that calls an existing dataset method
Artist.def_dataset_method(:server!)
Artist.server!(:server1)

Raises:



311
312
313
314
315
316
317
318
319
320
 
# File 'lib/sequel/model/base.rb', line 311

def def_dataset_method(*args, &block)
  raise(Error, "No arguments given") if args.empty?

  if block
    raise(Error, "Defining a dataset method using a block requires only one argument") if args.length > 1
    dataset_module{define_method(args.first, &block)}
  else
    args.each{|arg| def_model_dataset_method(arg)}
  end
end

#find(*args, &block) ⇒ Object

Finds a single record according to the supplied filter. You are encouraged to use Model.[] or Model.first instead of this method.

Artist.find(:name=>'Bob')
# SELECT * FROM artists WHERE (name = 'Bob') LIMIT 1

Artist.find{name > 'M'}
# SELECT * FROM artists WHERE (name > 'M') LIMIT 1



330
331
332
 
# File 'lib/sequel/model/base.rb', line 330

def find(*args, &block)
  filter(*args, &block).first
end

#find_or_create(cond, &block) ⇒ Object

Like find but invokes create with given conditions when record does not exist. Unlike find in that the block used in this method is not passed to find, but instead is passed to create only if find does not return an object.

Artist.find_or_create(:name=>'Bob')
# SELECT * FROM artists WHERE (name = 'Bob') LIMIT 1
# INSERT INTO artists (name) VALUES ('Bob')

Artist.find_or_create(:name=>'Jim'){|a| a.hometown = 'Sactown'}
# SELECT * FROM artists WHERE (name = 'Jim') LIMIT 1
# INSERT INTO artists (name, hometown) VALUES ('Jim', 'Sactown')



346
347
348
 
# File 'lib/sequel/model/base.rb', line 346

def find_or_create(cond, &block)
  find(cond) || create(cond, &block)
end

#implicit_table_name ⇒ Object

Returns the implicit table name for the model class, which is the demodulized, underscored, pluralized name of the class.

Artist.implicit_table_name # => :artists
Foo::ArtistAlias.implicit_table_name # => :artist_aliases



407
408
409
 
# File 'lib/sequel/model/base.rb', line 407

def implicit_table_name
  pluralize(underscore(demodulize(name))).to_sym
end

#include(mod) ⇒ Object

Clear the setter_methods cache when a module is included, as it may contain setter methods.



352
353
354
355
356
357
 
# File 'lib/sequel/model/base.rb', line 352

def include(mod)
  clear_setter_methods_cache
  check_deprecated_after_initialize(mod.instance_methods) unless allowed_after_initialize_implementation?(mod)
  Sequel::Deprecation.deprecate('Model#set_values', 'Please override Model.call, Model#_refresh_set_values, and/or Model#_create_set_values depending on the type of behavior you want to change') if mod.public_instance_methods.map{|x| x.to_s}.include?('set_values') && mod.name.to_s !~ /\ASequel::(Model|Model::Associations|Plugins::(ForceEncoding|Serialization|TypecastOnLoad|Composition|PreparedStatementsSafe|Dirty|PgTypecastOnLoad))::InstanceMethods\z/
  super
end

#inherited(subclass) ⇒ Object

If possible, set the dataset for the model subclass as soon as it is created. Also, make sure the inherited class instance variables are copied into the subclass.

Sequel queries the database to get schema information as soon as a model class is created:

class Artist < Sequel::Model # Causes schema query
end



368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
 
# File 'lib/sequel/model/base.rb', line 368

def inherited(subclass)
  super
  ivs = subclass.instance_variables.collect{|x| x.to_s}
  inherited_instance_variables.each do |iv, dup|
    next if ivs.include?(iv.to_s)
    if (sup_class_value = instance_variable_get(iv)) && dup
      sup_class_value = case dup
      when :dup
        sup_class_value.dup
      when :hash_dup
        h = {}
        sup_class_value.each{|k,v| h[k] = v.dup}
        h
      when Proc
        dup.call(sup_class_value)
      else
        raise Error, "bad inherited instance variable type: #{dup.inspect}"
      end
    end
    subclass.instance_variable_set(iv, sup_class_value)
  end
  unless ivs.include?("@dataset")
    if self == Model || !@dataset
      n = subclass.name
      unless n.nil? || n.empty?
        db
        subclass.set_dataset(subclass.implicit_table_name) rescue nil
      end
    elsif @dataset
      subclass.set_dataset(@dataset.clone, :inherited=>true) rescue nil
    end
  end
end

#load(values) ⇒ Object

Calls #call with the values hash. Only for backwards compatibility.



412
413
414
 
# File 'lib/sequel/model/base.rb', line 412

def load(values)
  call(values)
end

#method_added(meth) ⇒ Object

Clear the setter_methods cache when a setter method is added



417
418
419
420
421
422
 
# File 'lib/sequel/model/base.rb', line 417

def method_added(meth)
  clear_setter_methods_cache if meth.to_s =~ SETTER_METHOD_REGEXP
  check_deprecated_after_initialize(meth)
  Sequel::Deprecation.deprecate('Model#set_values', 'Please override Model.call, Model#_refresh_set_values, and/or Model#_create_set_values depending on the type of behavior you want to change') if meth.to_s == 'set_values'
  super
end

#no_primary_key ⇒ Object

Mark the model as not having a primary key. Not having a primary key can cause issues, among which is that you won’t be able to update records.

Artist.primary_key # => :id
Artist.no_primary_key
Artist.primary_key # => nil



430
431
432
433
 
# File 'lib/sequel/model/base.rb', line 430

def no_primary_key
  clear_setter_methods_cache
  self.simple_pk = @primary_key = nil
end

#plugin(plugin, *args, &block) ⇒ Object

Loads a plugin for use with the model class, passing optional arguments to the plugin. If the plugin is a module, load it directly. Otherwise, require the plugin from either sequel/plugins/##plugin or sequel_##plugin, and then attempt to load the module using a the camelized plugin name under Sequel::Plugins.



440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
 
# File 'lib/sequel/model/base.rb', line 440

def plugin(plugin, *args, &block)
  m = plugin.is_a?(Module) ? plugin : plugin_module(plugin)
  unless @plugins.include?(m)
    @plugins << m
    m.apply(self, *args, &block) if m.respond_to?(:apply)
    include(m::InstanceMethods) if plugin_module_defined?(m, :InstanceMethods)
    extend(m::ClassMethods)if plugin_module_defined?(m, :ClassMethods)
    if plugin_module_defined?(m, :DatasetMethods)
      dataset_extend(m::DatasetMethods, :create_class_methods=>false)
      # REMOVE40
      m::DatasetMethods.public_instance_methods.each do |meth|
        unless respond_to?(meth, true)
          (class << self; self; end).send(:define_method, meth) do |*args, &block|
            Sequel::Deprecation.deprecate('Automatically defining Model class methods for plugin public dataset methods', "Please modify the plugin to use Plugins.def_dataset_method for #{meth}")
            dataset.send(meth, *args, &block)
          end
        end
      end
    end
  end
  m.configure(self, *args, &block) if m.respond_to?(:configure)
end

#primary_key_hash(value) ⇒ Object

Returns primary key attribute hash. If using a composite primary key value such be an array with values for each primary key in the correct order. For a standard primary key, value should be an object with a compatible type for the key. If the model does not have a primary key, raises an Error.

Artist.primary_key_hash(1) # => {:id=>1}
Artist.primary_key_hash([1, 2]) # => {:id1=>1, :id2=>2}

Raises:



471
472
473
474
475
476
477
478
479
480
481
 
# File 'lib/sequel/model/base.rb', line 471

def primary_key_hash(value)
  raise(Error, "#{self} does not have a primary key") unless key = @primary_key
  case key
  when Array
    hash = {}
    key.each_with_index{|k,i| hash[k] = value[i]}
    hash
  else
    {key => value}
  end
end

#qualified_primary_key_hash(value, qualifier = table_name) ⇒ Object

Return a hash where the keys are qualified column references. Uses the given qualifier if provided, or the table_name otherwise. This is useful if you plan to join other tables to this table and you want the column references to be qualified.

Artist.filter(Artist.qualified_primary_key_hash(1))
# SELECT * FROM artists WHERE (artists.id = 1)



490
491
492
493
494
 
# File 'lib/sequel/model/base.rb', line 490

def qualified_primary_key_hash(value, qualifier=table_name)
  h = primary_key_hash(value)
  h.to_a.each{|k,v| h[SQL::QualifiedIdentifier.new(qualifier, k)] = h.delete(k)}
  h
end

#restrict_primary_key ⇒ Object

Restrict the setting of the primary key(s) when using mass assignment (e.g. set). Because this is the default, this only make sense to use in a subclass where the parent class has used unrestrict_primary_key.



499
500
501
502
 
# File 'lib/sequel/model/base.rb', line 499

def restrict_primary_key
  clear_setter_methods_cache
  @restrict_primary_key = true
end

#restrict_primary_key? ⇒ Boolean

Whether or not setting the primary key(s) when using mass assignment (e.g. set) is restricted, true by default.

Returns:

  • (Boolean) 


506
507
508
 
# File 'lib/sequel/model/base.rb', line 506

def restrict_primary_key?
  @restrict_primary_key
end

#restricted_columns ⇒ Object

REMOVE40



72
73
74
75
 
# File 'lib/sequel/model/base.rb', line 72

def restricted_columns
  Sequel::Deprecation.deprecate('Model.restricted_columns', 'Please load the blacklist_security plugin to continue using it')
  @restricted_columns
end

#set_allowed_columns(*cols) ⇒ Object

Set the columns to allow when using mass assignment (e.g. set). Using this means that any columns not listed here will not be modified. If you have any virtual setter methods (methods that end in =) that you want to be used during mass assignment, they need to be listed here as well (without the =).

It may be better to use a method such as set_only or set_fields that lets you specify the allowed fields per call.

Artist.set_allowed_columns(:name, :hometown)
Artist.set(:name=>'Bob', :hometown=>'Sactown') # No Error
Artist.set(:name=>'Bob', :records_sold=>30000) # Error



521
522
523
524
 
# File 'lib/sequel/model/base.rb', line 521

def set_allowed_columns(*cols)
  clear_setter_methods_cache
  @allowed_columns = cols
end

#set_dataset(ds, opts = {}) ⇒ Object

Sets the dataset associated with the Model class. ds can be a Symbol, LiteralString, SQL::Identifier, SQL::QualifiedIdentifier, SQL::AliasedExpression (all specifying a table name in the current database), or a Dataset. If a dataset is used, the model’s database is changed to the database of the given dataset. If a dataset is not used, a dataset is created from the current database with the table name given. Other arguments raise an Error. Returns self.

This changes the row_proc of the dataset to return model objects and extends the dataset with the dataset_method_modules. It also attempts to determine the database schema for the model, based on the given dataset.

Artist.set_dataset(:tbl_artists)
Artist.set_dataset(DB[:artists])

Note that you should not use this to change the model’s dataset at runtime. If you have that need, you should look into Sequel’s sharding support.



546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
 
# File 'lib/sequel/model/base.rb', line 546

def set_dataset(ds, opts={})
  inherited = opts[:inherited]
  case ds
  when Symbol, SQL::Identifier, SQL::QualifiedIdentifier, SQL::AliasedExpression, LiteralString
    self.simple_table = db.literal(ds)
    ds = db.from(ds)
  when Dataset
    self.simple_table = if ds.send(:simple_select_all?)
      ds.literal(ds.first_source_table)
    else
      nil
    end
    @db = ds.db
  else
    raise(Error, "Model.set_dataset takes one of the following classes as an argument: Symbol, LiteralString, SQL::Identifier, SQL::QualifiedIdentifier, SQL::AliasedExpression, Dataset")
  end
  set_dataset_row_proc(ds)
  @dataset = ds
  @require_modification = Sequel::Model.require_modification.nil? ? @dataset.provides_accurate_rows_matched? : Sequel::Model.require_modification
  if inherited
    self.simple_table = superclass.simple_table
    @columns = @dataset.columns rescue nil
  else
    @dataset_method_modules.each{|m| @dataset.extend(m)} if @dataset_method_modules
  end
  @dataset.model = self if @dataset.respond_to?(:model=)
  check_non_connection_error{@db_schema = (inherited ? superclass.db_schema : get_db_schema)}
  reset_instance_dataset
  self
end

#set_primary_key(*key) ⇒ Object

Sets the primary key for this model. You can use either a regular or a composite primary key. To not use a primary key, set to nil or use no_primary_key. On most adapters, Sequel can automatically determine the primary key to use, so this method is not needed often.

class Person < Sequel::Model
  # regular key
  set_primary_key :person_id
end

class Tagging < Sequel::Model
  # composite key
  set_primary_key [:taggable_id, :tag_id]
end



591
592
593
594
595
596
597
598
599
600
601
602
603
 
# File 'lib/sequel/model/base.rb', line 591

def set_primary_key(*key)
  Sequel::Deprecation.deprecate('Calling set_primary_key without arguments is deprecated and will raise an exception in Sequel 4. Please use no_primary_key to mark the model as not having a primary key.') if key.length == 0
  Sequel::Deprecation.deprecate('Calling set_primary_key with multiple arguments is deprecated and will raise an exception in Sequel 4. Please pass an array of keys to setup a composite primary key.') if key.length > 1
  
  clear_setter_methods_cache
  key = key.flatten
  self.simple_pk = if key.length == 1
    (@dataset || db).literal(key.first)
  else 
    nil 
  end
  @primary_key = (key.length == 1) ? key[0] : key
end

#set_restricted_columns(*cols) ⇒ Object

Set the columns to restrict when using mass assignment (e.g. set). Using this means that attempts to call setter methods for the columns listed here will cause an exception or be silently skipped (based on the strict_param_setting setting). If you have any virtual setter methods (methods that end in =) that you want not to be used during mass assignment, they need to be listed here as well (without the =).

It’s generally a bad idea to rely on a blacklist approach for security. Using a whitelist approach such as set_allowed_columns or the instance level set_only or set_fields methods is usually a better choice. So use of this method is generally a bad idea.

Artist.set_restricted_columns(:records_sold)
Artist.set(:name=>'Bob', :hometown=>'Sactown') # No Error
Artist.set(:name=>'Bob', :records_sold=>30000) # Error



618
619
620
621
622
 
# File 'lib/sequel/model/base.rb', line 618

def set_restricted_columns(*cols)
  clear_setter_methods_cache
  Sequel::Deprecation.deprecate('Model.set_restricted_columns', 'Please switch to Model.set_allowed_columns or use the blacklist_security plugin')
  @restricted_columns = cols
end

#setter_methods ⇒ Object

Cache of setter methods to allow by default, in order to speed up new/set/update instance methods.



625
626
627
628
629
630
631
632
633
634
 
# File 'lib/sequel/model/base.rb', line 625

def setter_methods
  @setter_methods ||= if allowed_columns
    allowed_columns.map{|x| "#{x}="}
  else
    meths = instance_methods.collect{|x| x.to_s}.grep(SETTER_METHOD_REGEXP) - RESTRICTED_SETTER_METHODS
    meths -= Array(primary_key).map{|x| "#{x}="} if primary_key && restrict_primary_key?
    meths -= _restricted_columns.map{|x| "#{x}="} if _restricted_columns
    meths
  end
end

#subset(name, *args, &block) ⇒ Object

Sets up a dataset method that returns a filtered dataset. Sometimes thought of as a scope, and like most dataset methods, they can be chained. For example:

Topic.subset(:joes, :username.like('%joe%'))
Topic.subset(:popular){num_posts > 100}
Topic.subset(:recent){created_on > Date.today - 7}

Allows you to do:

Topic.joes.recent.popular

to get topics with a username that includes joe that have more than 100 posts and were created less than 7 days ago.

Both the args given and the block are passed to Dataset#filter.

This method creates dataset methods that do not accept arguments. To create dataset methods that accept arguments, you should use define a method directly inside a #dataset_module block.



658
659
660
 
# File 'lib/sequel/model/base.rb', line 658

def subset(name, *args, &block)
  dataset_module.subset(name, *args, &block)
end

#table_name ⇒ Object

Returns name of primary table for the dataset. If the table for the dataset is aliased, returns the aliased name.

Artist.table_name # => :artists
Sequel::Model(:foo).table_name # => :foo
Sequel::Model(:foo___bar).table_name # => :bar



668
669
670
 
# File 'lib/sequel/model/base.rb', line 668

def table_name
  dataset.first_source_alias
end

#unrestrict_primary_key ⇒ Object

Allow the setting of the primary key(s) when using the mass assignment methods. Using this method can open up security issues, be very careful before using it.

Artist.set(:id=>1) # Error
Artist.unrestrict_primary_key
Artist.set(:id=>1) # No Error



678
679
680
681
 
# File 'lib/sequel/model/base.rb', line 678

def unrestrict_primary_key
  clear_setter_methods_cache
  @restrict_primary_key = false
end

#with_pk(pk) ⇒ Object

Return the model instance with the primary key, or nil if there is no matching record.



684
685
686
 
# File 'lib/sequel/model/base.rb', line 684

def with_pk(pk)
  primary_key_lookup(pk)
end

#with_pk!(pk) ⇒ Object

Return the model instance with the primary key, or raise NoMatchingRow if there is no matching record.



689
690
691
 
# File 'lib/sequel/model/base.rb', line 689

def with_pk!(pk)
  with_pk(pk) || raise(NoMatchingRow)
end