Module: Sequel::Model::InstanceMethods

Defined in:
lib/sequel/model/base.rb

Overview

Sequel::Model instance methods that implement basic model functionality.

  • All of the methods in HOOKS create instance methods that are called by Sequel when the appropriate action occurs. For example, when destroying a model object, Sequel will call before_destroy, do the destroy, and then call after_destroy.

  • The following instance_methods all call the class method of the same name: columns, dataset, db, primary_key, db_schema.

  • The following instance methods allow boolean flags to be set on a per-object basis: raise_on_save_failure, raise_on_typecast_failure, require_modification, strict_param_setting, typecast_empty_string_to_nil, typecast_on_assignment, use_transactions. If they are not used, the object will default to whatever the model setting is.

Instance Attribute Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#values ⇒ Object (readonly)

The hash of attribute values. Keys are symbols with the names of the underlying database columns.



531
532
533
 
# File 'lib/sequel/model/base.rb', line 531

def values
  @values
end

Instance Method Details

#==(obj) ⇒ Object Also known as: eql?

Compares model instances by values.



580
581
582
 
# File 'lib/sequel/model/base.rb', line 580

def ==(obj)
  (obj.class == model) && (obj.values == @values)
end

#===(obj) ⇒ Object

If pk is not nil, true only if the objects have the same class and pk. If pk is nil, false.



587
588
589
 
# File 'lib/sequel/model/base.rb', line 587

def ===(obj)
  pk.nil? ? false : (obj.class == model) && (obj.pk == pk)
end

#[](column) ⇒ Object

Returns value of the column’s attribute.



559
560
561
 
# File 'lib/sequel/model/base.rb', line 559

def [](column)
  @values[column]
end

#[]=(column, value) ⇒ Object

Sets the value for the given column. If typecasting is enabled for this object, typecast the value based on the column’s type. If this a a new record or the typecasted value isn’t the same as the current value for the column, mark the column as changed.



567
568
569
570
571
572
573
574
575
576
577
 
# File 'lib/sequel/model/base.rb', line 567

def []=(column, value)
  # If it is new, it doesn't have a value yet, so we should
  # definitely set the new value.
  # If the column isn't in @values, we can't assume it is
  # NULL in the database, so assume it has changed.
  v = typecast_value(column, value)
  if new? || !@values.include?(column) || v != @values[column]
    changed_columns << column unless changed_columns.include?(column)
    @values[column] = v
  end
end

#autoincrementing_primary_key ⇒ Object

The autoincrementing primary key for this model object. Should be overridden if you have a composite primary key with one part of it being autoincrementing.



600
601
602
 
# File 'lib/sequel/model/base.rb', line 600

def autoincrementing_primary_key
  primary_key
end

#changed_columns ⇒ Object

The columns that have been updated. This isn’t completely accurate, see Model#[]=.



606
607
608
 
# File 'lib/sequel/model/base.rb', line 606

def changed_columns
  @changed_columns ||= []
end

#delete ⇒ Object

Deletes and returns self. Does not run destroy hooks. Look into using destroy instead.



612
613
614
615
 
# File 'lib/sequel/model/base.rb', line 612

def delete
  _delete
  self
end

#destroy(opts = {}) ⇒ Object

Like delete but runs hooks before and after delete. If before_destroy returns false, returns false without deleting the object the the database. Otherwise, deletes the item from the database and returns self. Uses a transaction if use_transactions is true or if the :transaction option is given and true.



623
624
625
 
# File 'lib/sequel/model/base.rb', line 623

def destroy(opts = {})
  checked_save_failure{checked_transaction(opts){_destroy(opts)}}
end

#each(&block) ⇒ Object

Iterates through all of the current values using each.

Example:

Ticket.find(7).each { |k, v| puts "#{k} => #{v}" }



631
632
633
 
# File 'lib/sequel/model/base.rb', line 631

def each(&block)
  @values.each(&block)
end

#errors ⇒ Object

Returns the validation errors associated with this object.



636
637
638
 
# File 'lib/sequel/model/base.rb', line 636

def errors
  @errors ||= Errors.new
end

#exists? ⇒ Boolean

Returns true when current instance exists, false otherwise. Generally an object that isn’t new will exist unless it has been deleted.

Returns:

  • (Boolean) 


643
644
645
 
# File 'lib/sequel/model/base.rb', line 643

def exists?
  this.count > 0
end

#hash ⇒ Object

Value that should be unique for objects with the same class and pk (if pk is not nil), or the same class and values (if pk is nil).



649
650
651
 
# File 'lib/sequel/model/base.rb', line 649

def hash
  [model, pk.nil? ? @values.sort_by{|k,v| k.to_s} : pk].hash
end

#id ⇒ Object

Returns value for the :id attribute, even if the primary key is not id. To get the primary key value, use #pk.



655
656
657
 
# File 'lib/sequel/model/base.rb', line 655

def id
  @values[:id]
end

#initialize(values = {}, from_db = false) ⇒ Object

Creates new instance and passes the given values to set. If a block is given, yield the instance to the block unless from_db is true. This method runs the after_initialize hook after it has optionally yielded itself to the block.

Arguments:

  • values - should be a hash to pass to set.

  • from_db - should only be set by Model.load, forget it exists.



543
544
545
546
547
548
549
550
551
552
553
554
555
556
 
# File 'lib/sequel/model/base.rb', line 543

def initialize(values = {}, from_db = false)
  if from_db
    @new = false
    set_values(values)
  else
    @values = {}
    @new = true
    @modified = true
    set(values)
    changed_columns.clear 
    yield self if block_given?
  end
  after_initialize
end

#inspect ⇒ Object

Returns a string representation of the model instance including the class name and values.



661
662
663
 
# File 'lib/sequel/model/base.rb', line 661

def inspect
  "#<#{model.name} @values=#{inspect_values}>"
end

#keys ⇒ Object

Returns the keys in values. May not include all column names.



666
667
668
 
# File 'lib/sequel/model/base.rb', line 666

def keys
  @values.keys
end

#lock! ⇒ Object

Refresh this record using for_update unless this is a new record. Returns self.



671
672
673
 
# File 'lib/sequel/model/base.rb', line 671

def lock!
  new? ? self : _refresh(this.for_update)
end

#marshallable! ⇒ Object

Remove elements of the model object that make marshalling fail. Returns self.



676
677
678
679
 
# File 'lib/sequel/model/base.rb', line 676

def marshallable!
  @this = nil
  self
end

#modified! ⇒ Object

Explicitly mark the object as modified, so save_changes/update will run callbacks even if no columns have changed.



683
684
685
 
# File 'lib/sequel/model/base.rb', line 683

def modified!
  @modified = true
end

#modified? ⇒ Boolean

Whether this object has been modified since last saved, used by save_changes to determine whether changes should be saved. New values are always considered modified.

Returns:

  • (Boolean) 


690
691
692
 
# File 'lib/sequel/model/base.rb', line 690

def modified?
  @modified || !changed_columns.empty?
end

#new? ⇒ Boolean

Returns true if the current instance represents a new record.

Returns:

  • (Boolean) 


695
696
697
 
# File 'lib/sequel/model/base.rb', line 695

def new?
  @new
end

#pk ⇒ Object

Returns the primary key value identifying the model instance. Raises an error if this model does not have a primary key. If the model has a composite primary key, returns an array of values.

Raises:



702
703
704
705
 
# File 'lib/sequel/model/base.rb', line 702

def pk
  raise(Error, "No primary key is associated with this model") unless key = primary_key
  key.is_a?(Array) ? key.map{|k| @values[k]} : @values[key]
end

#pk_hash ⇒ Object

Returns a hash identifying the model instance. It should be true that:

Model[model_instance.pk_hash] === model_instance



710
711
712
 
# File 'lib/sequel/model/base.rb', line 710

def pk_hash
  model.primary_key_hash(pk)
end

#refresh ⇒ Object

Reloads attributes from database and returns self. Also clears all cached association and changed_columns information. Raises an Error if the record no longer exists in the database.



717
718
719
 
# File 'lib/sequel/model/base.rb', line 717

def refresh
  _refresh(this)
end

#reload ⇒ Object

Alias of refresh, but not aliased directly to make overriding in a plugin easier.



722
723
724
 
# File 'lib/sequel/model/base.rb', line 722

def reload
  refresh
end

#save(*columns) ⇒ Object

Creates or updates the record, after making sure the record is valid. If the record is not valid, or before_save, before_create (if new?), or before_update (if !new?) return false, returns nil unless raise_on_save_failure is true (if it is true, it raises an error). Otherwise, returns self. You can provide an optional list of columns to update, in which case it only updates those columns.

Takes the following options:

  • :changed - save all changed columns, instead of all columns or the columns given

  • :transaction - set to false not to use a transaction

  • :validate - set to false not to validate the model before saving



739
740
741
742
743
744
745
746
 
# File 'lib/sequel/model/base.rb', line 739

def save(*columns)
  opts = columns.last.is_a?(Hash) ? columns.pop : {}
  if opts[:validate] != false and !valid?
    raise(ValidationFailed.new(errors)) if raise_on_save_failure
    return
  end
  checked_save_failure{checked_transaction(opts){_save(columns, opts)}}
end

#save_changes(opts = {}) ⇒ Object

Saves only changed columns if the object has been modified. If the object has not been modified, returns nil. If unable to save, returns false unless raise_on_save_failure is true.



751
752
753
 
# File 'lib/sequel/model/base.rb', line 751

def save_changes(opts={})
  save(opts.merge(:changed=>true)) || false if modified? 
end

#set(hash) ⇒ Object

Updates the instance with the supplied values with support for virtual attributes, raising an exception if a value is used that doesn’t have a setter method (or ignoring it if strict_param_setting = false). Does not save the record.



759
760
761
 
# File 'lib/sequel/model/base.rb', line 759

def set(hash)
  set_restricted(hash, nil, nil)
end

#set_all(hash) ⇒ Object

Set all values using the entries in the hash, ignoring any setting of allowed_columns or restricted columns in the model.



765
766
767
 
# File 'lib/sequel/model/base.rb', line 765

def set_all(hash)
  set_restricted(hash, false, false)
end

#set_except(hash, *except) ⇒ Object

Set all values using the entries in the hash, except for the keys given in except.



771
772
773
 
# File 'lib/sequel/model/base.rb', line 771

def set_except(hash, *except)
  set_restricted(hash, false, except.flatten)
end

#set_only(hash, *only) ⇒ Object

Set the values using the entries in the hash, only if the key is included in only.



777
778
779
 
# File 'lib/sequel/model/base.rb', line 777

def set_only(hash, *only)
  set_restricted(hash, only.flatten, false)
end

#this ⇒ Object

Returns (naked) dataset that should return only this instance.



782
783
784
 
# File 'lib/sequel/model/base.rb', line 782

def this
  @this ||= model.dataset.filter(pk_hash).limit(1).naked
end

#update(hash) ⇒ Object

Runs set with the passed hash and then runs save_changes.



787
788
789
 
# File 'lib/sequel/model/base.rb', line 787

def update(hash)
  update_restricted(hash, nil, nil)
end

#update_all(hash) ⇒ Object

Update all values using the entries in the hash, ignoring any setting of allowed_columns or restricted columns in the model.



793
794
795
 
# File 'lib/sequel/model/base.rb', line 793

def update_all(hash)
  update_restricted(hash, false, false)
end

#update_except(hash, *except) ⇒ Object

Update all values using the entries in the hash, except for the keys given in except.



799
800
801
 
# File 'lib/sequel/model/base.rb', line 799

def update_except(hash, *except)
  update_restricted(hash, false, except.flatten)
end

#update_only(hash, *only) ⇒ Object

Update the values using the entries in the hash, only if the key is included in only.



805
806
807
 
# File 'lib/sequel/model/base.rb', line 805

def update_only(hash, *only)
  update_restricted(hash, only.flatten, false)
end

#valid? ⇒ Boolean

Validates the object and returns true if no errors are reported.

Returns:

  • (Boolean) 


816
817
818
819
820
821
822
823
824
825
 
# File 'lib/sequel/model/base.rb', line 816

def valid?
  errors.clear
  if before_validation == false
    save_failure(:validation) if raise_on_save_failure
    return false
  end
  validate
  after_validation
  errors.empty?
end

#validate ⇒ Object

Validates the object. If the object is invalid, errors should be added to the errors attribute. By default, does nothing, as all models are valid by default.



812
813
 
# File 'lib/sequel/model/base.rb', line 812

def validate
end