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

#valuesObject (readonly)

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



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# File 'lib/sequel/model/base.rb', line 543

def values
  @values
end

Instance Method Details

#==(obj) ⇒ Object

Alias of eql?



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# File 'lib/sequel/model/base.rb', line 592

def ==(obj)
  eql?(obj)
end

#===(obj) ⇒ Object

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



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# File 'lib/sequel/model/base.rb', line 598

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

#[](column) ⇒ Object

Returns value of the column’s attribute.



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# File 'lib/sequel/model/base.rb', line 571

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.



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# File 'lib/sequel/model/base.rb', line 579

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_keyObject

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.



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# File 'lib/sequel/model/base.rb', line 611

def autoincrementing_primary_key
  primary_key
end

#changed_columnsObject

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



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# File 'lib/sequel/model/base.rb', line 617

def changed_columns
  @changed_columns ||= []
end

#deleteObject

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



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

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.



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# File 'lib/sequel/model/base.rb', line 634

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}" }


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# File 'lib/sequel/model/base.rb', line 642

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

#eql?(obj) ⇒ Boolean

Compares model instances by values.

Returns:

  • (Boolean)


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# File 'lib/sequel/model/base.rb', line 647

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

#errorsObject

Returns the validation errors associated with this object.



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# File 'lib/sequel/model/base.rb', line 652

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)


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

def exists?
  this.count > 0
end

#hashObject

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).



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# File 'lib/sequel/model/base.rb', line 665

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

#idObject

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



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

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.



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# File 'lib/sequel/model/base.rb', line 555

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

#inspectObject

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



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

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

#keysObject

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



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# File 'lib/sequel/model/base.rb', line 682

def keys
  @values.keys
end

#lock!Object

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



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# File 'lib/sequel/model/base.rb', line 687

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

#marshallable!Object

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



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

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.



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# File 'lib/sequel/model/base.rb', line 699

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)


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# File 'lib/sequel/model/base.rb', line 706

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

#new?Boolean

Returns true if the current instance represents a new record.

Returns:

  • (Boolean)


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

def new?
  @new
end

#pkObject

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:



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

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_hashObject

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

Model[model_instance.pk_hash] === model_instance


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# File 'lib/sequel/model/base.rb', line 726

def pk_hash
  model.primary_key_hash(pk)
end

#refreshObject

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.



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# File 'lib/sequel/model/base.rb', line 733

def refresh
  _refresh(this)
end

#reloadObject

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



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# File 'lib/sequel/model/base.rb', line 738

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



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# File 'lib/sequel/model/base.rb', line 755

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.



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

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.



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# File 'lib/sequel/model/base.rb', line 775

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.



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# File 'lib/sequel/model/base.rb', line 781

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.



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

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

#set_fields(hash, fields) ⇒ Object

For each of the fields in the given array fields, call the setter method with the value of that hash entry for the field. Returns self.



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

def set_fields(hash, fields)
  fields.each{|f| send("#{f}=", hash[f])}
  self
end

#set_only(hash, *only) ⇒ Object

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



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

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

#thisObject

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



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

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.



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# File 'lib/sequel/model/base.rb', line 810

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.



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# File 'lib/sequel/model/base.rb', line 816

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.



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# File 'lib/sequel/model/base.rb', line 822

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

#update_fields(hash, fields) ⇒ Object

Update the instances values by calling set_fields with the hash and fields, then save any changes to the record. Returns self.



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# File 'lib/sequel/model/base.rb', line 828

def update_fields(hash, fields)
  set_fields(hash, fields)
  save_changes
end

#update_only(hash, *only) ⇒ Object

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



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# File 'lib/sequel/model/base.rb', line 835

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)


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# File 'lib/sequel/model/base.rb', line 847

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

#validateObject

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. See the “Model Validations” guide. for details about validation.



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# File 'lib/sequel/model/base.rb', line 843

def validate
end