module Sequel::Model::ClassMethods

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

Attributes

cache_anonymous_models[RW]

Whether to cache the anonymous models created by Sequel::Model(), true by default. This is required for reloading them correctly (avoiding the superclass mismatch).

dataset_method_modules[R]

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.

dataset_module_class[R]

The Module subclass to use for dataset_module blocks.

default_set_fields_options[RW]

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

fast_instance_delete_sql[R]

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.

fast_pk_lookup_sql[R]

SQL string fragment used for faster lookups by primary key, or nil if the optimization should not be used. For internal use only.

instance_dataset[R]

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.

plugins[R]

Array of plugin modules loaded by this class

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

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.

raise_on_save_failure[RW]

Whether to raise an error instead of returning nil on a failure to save/create/save_changes/update/destroy due to a validation failure or a before_* hook returning false (default: true).

raise_on_typecast_failure[RW]

Whether to raise an error when unable to typecast data for a column (default: false). This should be set to true if you want to have model setter methods raise errors if the argument cannot be typecast properly.

require_modification[RW]

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).

require_valid_table[RW]

If true (the default), requires that all models have valid tables, raising exceptions if creating a model without a valid table backing it. Setting this to false will allow the creation of model classes where the underlying table doesn’t exist.

simple_pk[R]

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.

simple_table[R]

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.[].

strict_param_setting[RW]

Whether mass assigning via .create/.new/#set/#update 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.

typecast_empty_string_to_nil[RW]

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.

typecast_on_assignment[RW]

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.

use_transactions[RW]

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.

Public Instance Methods

Model(source) click to toggle source

Lets you create a Model subclass with its dataset already set. source should be an instance of one of the following classes:

Database

Sets the database for this model to source. Generally only useful when subclassing directly from the returned class, where the name of the subclass sets the table name (which is combined with the Database in source to create the dataset to use)

Dataset

Sets the dataset for this model to source.

other

Sets the table name for this model to source. The class will use the default database for model classes in order to create the dataset.

The purpose of this method is to set the dataset/database automatically for a model class, if the table name doesn’t match the default table name that Sequel would use.

When creating subclasses of Sequel::Model itself, this method is usually called on Sequel itself, using Sequel::Model(:something).

# Using a symbol
class Comment < Sequel::Model(:something)
  table_name # => :something
end

# Using a dataset
class Comment < Sequel::Model(DB1[:something])
  dataset # => DB1[:something]
end

# Using a database
class Comment < Sequel::Model(DB1)
  dataset # => DB1[:comments]
end
    # File lib/sequel/model/base.rb
179 def Model(source)
180   if cache_anonymous_models
181     cache = Sequel.synchronize{@Model_cache ||= {}}
182     if klass = Sequel.synchronize{cache[source]}
183       return klass
184     end
185   end
186 
187   klass = Class.new(self)
188 
189   if source.is_a?(::Sequel::Database)
190     klass.db = source
191   else
192     klass.set_dataset(source)
193   end
194 
195   if cache_anonymous_models
196     Sequel.synchronize{cache[source] = klass}
197   end
198 
199   klass
200 end
[](*args) click to toggle source

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', ...}>
    # File lib/sequel/model/base.rb
212 def [](*args)
213   args = args.first if args.size <= 1
214   args.is_a?(Hash) ? first(args) : (primary_key_lookup(args) unless args.nil?)
215 end
call(values) click to toggle source

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.

    # File lib/sequel/model/base.rb
221 def call(values)
222   o = allocate
223   o.instance_variable_set(:@values, values)
224   o
225 end
clear_setter_methods_cache() click to toggle source

Clear the setter_methods cache

    # File lib/sequel/model/base.rb
228 def clear_setter_methods_cache
229   @setter_methods = nil unless frozen?
230 end
columns() click to toggle source

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]
    # File lib/sequel/model/base.rb
239 def columns
240   return @columns if @columns
241   return nil if frozen?
242   set_columns(dataset.naked.columns)
243 end
create(values = OPTS, &block) click to toggle source

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')
    # File lib/sequel/model/base.rb
253 def create(values = OPTS, &block)
254   new(values, &block).save
255 end
dataset() click to toggle source

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
    # File lib/sequel/model/base.rb
263 def dataset
264   @dataset || raise(Error, "No dataset associated with #{self}")
265 end
dataset=(ds) click to toggle source

Alias of set_dataset

    # File lib/sequel/model/base.rb
268 def dataset=(ds)
269   set_dataset(ds)
270 end
dataset_module(mod = nil, &block) click to toggle source

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 given 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
Album.dataset_module Sequel::ColumnsIntrospection

# Usage with anonymous module
Album.dataset_module do
  def foo
    :bar
  end
end
Album.dataset.foo
# => :bar
Album.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, which defines a dataset method that adds a filter. There are also a number of other methods with the same names as the dataset methods, which can use to define named dataset methods:

Album.dataset_module do
  where(:released, Sequel[:release_date] <= Sequel::CURRENT_DATE)
  order :by_release_date, :release_date
  select :for_select_options, :id, :name, :release_date
end
Album.released.sql
# => "SELECT * FROM artists WHERE (release_date <= CURRENT_DATE)"
Album.by_release_date.sql
# => "SELECT * FROM artists ORDER BY release_date"
Album.for_select_options.sql
# => "SELECT id, name, release_date FROM artists"
Album.released.by_release_date.for_select_options.sql
# => "SELECT id, name, release_date FROM artists WHERE (release_date <= CURRENT_DATE) ORDER BY release_date"

The following methods are supported: distinct, eager, exclude, exclude_having, grep, group, group_and_count, group_append, having, limit, offset, order, order_append, order_prepend, select, select_all, select_append, select_group, where, and server.

The advantage of using these DatasetModule methods to define your dataset methods is that they can take advantage of dataset caching to improve performance.

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.

    # File lib/sequel/model/base.rb
327 def dataset_module(mod = nil, &block)
328   if mod
329     raise Error, "can't provide both argument and block to Model.dataset_module" if block
330     dataset_extend(mod)
331     mod
332   else
333     @dataset_module ||= dataset_module_class.new(self)
334     @dataset_module.module_eval(&block) if block
335     dataset_extend(@dataset_module)
336     @dataset_module
337   end
338 end
db() click to toggle source

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
    # File lib/sequel/model/base.rb
350 def db
351   return @db if @db
352   @db = self == Model ? Sequel.synchronize{DATABASES.first} : superclass.db
353   raise(Error, "No database associated with #{self}: have you called Sequel.connect or #{self}.db= ?") unless @db
354   @db
355 end
db=(db) click to toggle source

Sets the database associated with the Model class. Should only be used if the Model class currently does not have a dataset defined.

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 = Class.new(Sequel::Model)
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, or consider using separate model classes per Database.

    # File lib/sequel/model/base.rb
371 def db=(db)
372   raise Error, "Cannot use Sequel::Model.db= on model with existing dataset.  Use Sequel::Model.dataset= instead." if @dataset
373   @db = db
374 end
db_schema() click to toggle source

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, ...}}
    # File lib/sequel/model/base.rb
384 def db_schema
385   return @db_schema if @db_schema
386   return nil if frozen?
387   @db_schema = get_db_schema
388 end
def_Model(mod) click to toggle source

Define a Model method on the given module that calls the Model method on the receiver. This is how the Sequel::Model() method is defined, and allows you to define Model() methods on other modules, making it easier to have custom model settings for all models under a namespace. Example:

module Foo
  Model = Class.new(Sequel::Model)
  Model.def_Model(self)
  DB = Model.db = Sequel.connect(ENV['FOO_DATABASE_URL'])
  Model.plugin :prepared_statements

  class Bar < Model
    # Uses Foo::DB[:bars]
  end

  class Baz < Model(:my_baz)
    # Uses Foo::DB[:my_baz]
  end
end
    # File lib/sequel/model/base.rb
137 def def_Model(mod)
138   model = self
139   mod.define_singleton_method(:Model) do |source|
140     model.Model(source)
141   end
142 end
def_column_alias(meth, column) click to toggle source

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

    # File lib/sequel/model/base.rb
392 def def_column_alias(meth, column)
393   clear_setter_methods_cache
394   overridable_methods_module.module_eval do
395     define_method(meth){self[column]}
396     define_method("#{meth}="){|v| self[column] = v}
397   end
398 end
find(*args, &block) click to toggle source

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
    # File lib/sequel/model/base.rb
408 def find(*args, &block)
409   first(*args, &block)
410 end
find_or_create(cond, &block) click to toggle source

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')
    # File lib/sequel/model/base.rb
424 def find_or_create(cond, &block)
425   find(cond) || create(cond, &block)
426 end
freeze() click to toggle source

Freeze a model class, disallowing any further changes to it.

Calls superclass method
    # File lib/sequel/model/base.rb
429 def freeze
430   return self if frozen?
431   dataset_module.freeze
432   overridable_methods_module.freeze
433 
434   if @dataset
435     db_schema.freeze.each_value(&:freeze)
436     columns.freeze
437     setter_methods.freeze
438   else
439     @setter_methods = [].freeze
440   end
441 
442   @dataset_method_modules.freeze
443   @default_set_fields_options.freeze
444   @plugins.freeze
445 
446   super
447 end
has_dataset?() click to toggle source

Whether the model has a dataset. True for most model classes, but can be false if the model class is an abstract model class designed for subclassing, such as Sequel::Model itself.

    # File lib/sequel/model/base.rb
452 def has_dataset?
453   !@dataset.nil?
454 end
implicit_table_name() click to toggle source

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
    # File lib/sequel/model/base.rb
468 def implicit_table_name
469   pluralize(underscore(demodulize(name))).to_sym
470 end
include(*mods) click to toggle source

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

Calls superclass method
    # File lib/sequel/model/base.rb
458 def include(*mods)
459   clear_setter_methods_cache
460   super
461 end
load(values) click to toggle source

Calls call with the values hash.

    # File lib/sequel/model/base.rb
473 def load(values)
474   call(values)
475 end
no_primary_key() click to toggle source

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
    # File lib/sequel/model/base.rb
483 def no_primary_key
484   clear_setter_methods_cache
485   self.simple_pk = @primary_key = nil
486 end
plugin(plugin, *args, &block) click to toggle source

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 sequel/plugins/#{plugin} and then attempt to load the module using a the camelized plugin name under Sequel::Plugins.

    # File lib/sequel/model/base.rb
492 def plugin(plugin, *args, &block)
493   m = plugin.is_a?(Module) ? plugin : plugin_module(plugin)
494 
495   if !m.respond_to?(:apply) && !m.respond_to?(:configure) && (!args.empty? || block)
496     Deprecation.deprecate("Plugin #{plugin} accepts no arguments or block, and passing arguments/block to it", "Remove arguments and block when loading the plugin")
497   end
498 
499   unless @plugins.include?(m)
500     @plugins << m
501     m.apply(self, *args, &block) if m.respond_to?(:apply)
502     extend(m::ClassMethods) if m.const_defined?(:ClassMethods, false)
503     include(m::InstanceMethods) if m.const_defined?(:InstanceMethods, false)
504     if m.const_defined?(:DatasetMethods, false)
505       dataset_extend(m::DatasetMethods, :create_class_methods=>false)
506     end
507   end
508 
509   m.configure(self, *args, &block) if m.respond_to?(:configure)
510 end
primary_key_hash(value) click to toggle source

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}
    # File lib/sequel/model/base.rb
523 def primary_key_hash(value)
524   case key = @primary_key
525   when Symbol
526     {key => value}
527   when Array
528     hash = {}
529     key.zip(Array(value)){|k,v| hash[k] = v}
530     hash
531   else
532     raise(Error, "#{self} does not have a primary key")
533   end
534 end
qualified_primary_key_hash(value, qualifier=table_name) click to toggle source

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.where(Artist.qualified_primary_key_hash(1))
# SELECT * FROM artists WHERE (artists.id = 1)
    # File lib/sequel/model/base.rb
543 def qualified_primary_key_hash(value, qualifier=table_name)
544   case key = @primary_key
545   when Symbol
546     {SQL::QualifiedIdentifier.new(qualifier, key) => value}
547   when Array
548     hash = {}
549     key.zip(Array(value)){|k,v| hash[SQL::QualifiedIdentifier.new(qualifier, k)] = v}
550     hash
551   else
552     raise(Error, "#{self} does not have a primary key")
553   end
554 end
restrict_primary_key() click to toggle source

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.

    # File lib/sequel/model/base.rb
559 def restrict_primary_key
560   clear_setter_methods_cache
561   @restrict_primary_key = true
562 end
restrict_primary_key?() click to toggle source

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

    # File lib/sequel/model/base.rb
566 def restrict_primary_key?
567   @restrict_primary_key
568 end
set_dataset(ds, opts=OPTS) click to toggle source

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.

It also attempts to determine the database schema for the model, based on the given dataset.

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, or creating a separate Model class per dataset

You should avoid calling this method directly if possible. Instead you should set the table name or dataset when creating the model class:

# table name
class Artist < Sequel::Model(:tbl_artists)
end

# dataset
class Artist < Sequel::Model(DB[:tbl_artists])
end
    # File lib/sequel/model/base.rb
596 def set_dataset(ds, opts=OPTS)
597   inherited = opts[:inherited]
598   @dataset = convert_input_dataset(ds)
599   @require_modification = @dataset.provides_accurate_rows_matched? if require_modification.nil?
600   if inherited
601     self.simple_table = superclass.simple_table
602     @columns = superclass.instance_variable_get(:@columns)
603     @db_schema = superclass.instance_variable_get(:@db_schema)
604   else
605     @dataset = @dataset.with_extend(*@dataset_method_modules.reverse)
606     @db_schema = get_db_schema
607   end
608 
609   @fast_pk_lookup_sql = @fast_instance_delete_sql = nil unless @dataset.supports_placeholder_literalizer?
610   reset_instance_dataset
611   self
612 end
set_primary_key(key) click to toggle source

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
    # File lib/sequel/model/base.rb
628 def set_primary_key(key)
629   clear_setter_methods_cache
630   if key.is_a?(Array)
631     if key.length < 2
632       key = key.first
633     else
634       key = key.dup.freeze
635     end
636   end
637   self.simple_pk = if key && !key.is_a?(Array)
638     (@dataset || db).literal(key).freeze
639   end
640   @primary_key = key
641 end
setter_methods() click to toggle source

Cache of setter methods to allow by default, in order to speed up mass assignment.

    # File lib/sequel/model/base.rb
644 def setter_methods
645   @setter_methods || (@setter_methods = get_setter_methods)
646 end
table_name() click to toggle source

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(Sequel[:foo].as(:bar)).table_name # => :bar
    # File lib/sequel/model/base.rb
654 def table_name
655   dataset.first_source_alias
656 end
unrestrict_primary_key() click to toggle source

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
    # File lib/sequel/model/base.rb
664 def unrestrict_primary_key
665   clear_setter_methods_cache
666   @restrict_primary_key = false
667 end
with_pk(pk) click to toggle source

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

    # File lib/sequel/model/base.rb
670 def with_pk(pk)
671   primary_key_lookup(pk)
672 end
with_pk!(pk) click to toggle source

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

    # File lib/sequel/model/base.rb
675 def with_pk!(pk)
676   with_pk(pk) || raise(NoMatchingRow.new(dataset))
677 end

Private Instance Methods

check_non_connection_error(do_raise=require_valid_table) { || ... } click to toggle source

Yield to the passed block and if do_raise is false, swallow Sequel::Errors other than DatabaseConnectionError and DatabaseDisconnectError.

    # File lib/sequel/model/base.rb
686 def check_non_connection_error(do_raise=require_valid_table)
687   db.transaction(:savepoint=>:only){yield}
688 rescue Sequel::DatabaseConnectionError, Sequel::DatabaseDisconnectError
689   raise
690 rescue Sequel::Error
691   raise if do_raise
692 end
convert_input_dataset(ds) click to toggle source

Convert the given object to a Dataset that should be used as this model’s dataset.

    # File lib/sequel/model/base.rb
696 def convert_input_dataset(ds)
697   case ds
698   when Symbol, SQL::Identifier, SQL::QualifiedIdentifier
699     self.simple_table = db.literal(ds).freeze
700     ds = db.from(ds)
701   when SQL::AliasedExpression, LiteralString
702     self.simple_table = nil
703     ds = db.from(ds)
704   when Dataset
705     ds = ds.from_self(:alias=>ds.first_source) if ds.joined_dataset?
706 
707     self.simple_table = if ds.send(:simple_select_all?)
708       ds.literal(ds.first_source_table).freeze
709     end
710     @db = ds.db
711   else
712     raise(Error, "Model.set_dataset takes one of the following classes as an argument: Symbol, LiteralString, SQL::Identifier, SQL::QualifiedIdentifier, SQL::AliasedExpression, Dataset")
713   end
714 
715   set_dataset_row_proc(ds.clone(:model=>self))
716 end
dataset_extend(mod, opts=OPTS) click to toggle source

Add the module to the class’s dataset_method_modules. Extend the dataset with the module if the model has a dataset. Add dataset methods to the class for all public dataset methods.

    # File lib/sequel/model/base.rb
721 def dataset_extend(mod, opts=OPTS)
722   @dataset = @dataset.with_extend(mod) if @dataset
723   reset_instance_dataset
724   dataset_method_modules << mod
725   unless opts[:create_class_methods] == false
726     mod.public_instance_methods.each{|meth| def_model_dataset_method(meth)}
727   end
728 end
def_bad_column_accessor(column) click to toggle source

Create a column accessor for a column with a method name that is hard to use in ruby code.

    # File lib/sequel/model/base.rb
731 def def_bad_column_accessor(column)
732   im = instance_methods
733   overridable_methods_module.module_eval do
734     meth = :"#{column}="
735     unless im.include?(column)
736       define_method(column){self[column]}
737       alias_method(column, column)
738     end
739     unless im.include?(meth)
740       define_method(meth){|v| self[column] = v}
741       alias_method(meth, meth)
742     end
743   end
744 end
def_column_accessor(*columns) click to toggle source

Create the column accessors. For columns that can be used as method names directly in ruby code, use a string to define the method for speed. For other columns names, use a block.

    # File lib/sequel/model/base.rb
748 def def_column_accessor(*columns)
749   clear_setter_methods_cache
750   columns, bad_columns = columns.partition{|x| /\A[A-Za-z_][A-Za-z0-9_]*\z/.match(x.to_s)}
751   bad_columns.each{|x| def_bad_column_accessor(x)}
752   im = instance_methods
753   columns.each do |column|
754     meth = :"#{column}="
755     unless im.include?(column)
756       overridable_methods_module.module_eval("def #{column}; self[:#{column}] end", __FILE__, __LINE__)
757       overridable_methods_module.send(:alias_method, column, column)
758     end
759     unless im.include?(meth)
760       overridable_methods_module.module_eval("def #{meth}(v); self[:#{column}] = v end", __FILE__, __LINE__)
761       overridable_methods_module.send(:alias_method, meth, meth)
762     end
763   end
764 end
def_model_dataset_method(meth) click to toggle source

Define a model method that calls the dataset method with the same name, only used for methods with names that can’t be represented directly in ruby code.

    # File lib/sequel/model/base.rb
769 def def_model_dataset_method(meth)
770   return if respond_to?(meth, true)
771 
772   if meth.to_s =~ /\A[A-Za-z_][A-Za-z0-9_]*\z/
773     instance_eval("def #{meth}(*args, &block); dataset.#{meth}(*args, &block) end", __FILE__, __LINE__)
774   else
775     define_singleton_method(meth){|*args, &block| dataset.public_send(meth, *args, &block)}
776   end
777   singleton_class.send(:alias_method, meth, meth)
778   # :nocov:
779   singleton_class.send(:ruby2_keywords, meth) if respond_to?(:ruby2_keywords, true)
780   # :nocov:
781 end
get_db_schema(reload = reload_db_schema?) click to toggle source

Get the schema from the database, fall back on checking the columns via the database if that will return inaccurate results or if it raises an error.

    # File lib/sequel/model/base.rb
786 def get_db_schema(reload = reload_db_schema?)
787   set_columns(nil)
788   return nil unless @dataset
789   schema_hash = {}
790   ds_opts = dataset.opts
791   get_columns = proc{check_non_connection_error{columns} || []}
792   schema_array = get_db_schema_array(reload) if db.supports_schema_parsing?
793   if schema_array
794     schema_array.each{|k,v| schema_hash[k] = v}
795 
796     # Set the primary key(s) based on the schema information,
797     # if the schema information includes primary key information
798     if schema_array.all?{|k,v| v.has_key?(:primary_key)}
799       pks = schema_array.map{|k,v| k if v[:primary_key]}.compact
800       pks.length > 0 ? set_primary_key(pks) : no_primary_key
801     end
802 
803     if (select = ds_opts[:select]) && !(select.length == 1 && select.first.is_a?(SQL::ColumnAll))
804       # We don't remove the columns from the schema_hash,
805       # as it's possible they will be used for typecasting
806       # even if they are not selected.
807       cols = get_columns.call
808       cols.each{|c| schema_hash[c] ||= {}}
809       def_column_accessor(*schema_hash.keys)
810     else
811       # Dataset is for a single table with all columns,
812       # so set the columns based on the order they were
813       # returned by the schema.
814       cols = schema_array.map{|k,v| k}
815       set_columns(cols)
816       # Also set the columns for the dataset, so the dataset
817       # doesn't have to do a query to get them.
818       dataset.send(:columns=, cols)
819     end
820   else
821     # If the dataset uses multiple tables or custom sql or getting
822     # the schema raised an error, just get the columns and
823     # create an empty schema hash for it.
824     get_columns.call.each{|c| schema_hash[c] = {}}
825   end
826   schema_hash
827 end
get_db_schema_array(reload) click to toggle source

Get the array of schema information for the dataset. Returns nil if the schema information cannot be determined.

    # File lib/sequel/model/base.rb
831 def get_db_schema_array(reload)
832   check_non_connection_error(false){db.schema(dataset, :reload=>reload)}
833 end
get_setter_methods() click to toggle source

Uncached version of setter_methods, to be overridden by plugins that want to modify the methods used.

    # File lib/sequel/model/base.rb
837 def get_setter_methods
838   meths = instance_methods.map(&:to_s).select{|l| l.end_with?('=')} - RESTRICTED_SETTER_METHODS
839   meths -= Array(primary_key).map{|x| "#{x}="} if primary_key && restrict_primary_key?
840   meths
841 end
inherited(subclass) click to toggle source

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
Calls superclass method
    # File lib/sequel/model/base.rb
852 def inherited(subclass)
853   super
854   ivs = subclass.instance_variables
855   inherited_instance_variables.each do |iv, dup|
856     if (sup_class_value = instance_variable_get(iv)) && dup
857       sup_class_value = case dup
858       when :dup
859         sup_class_value.dup
860       when :hash_dup
861         h = {}
862         sup_class_value.each{|k,v| h[k] = v.dup}
863         h
864       when Proc
865         dup.call(sup_class_value)
866       else
867         raise Error, "bad inherited instance variable type: #{dup.inspect}"
868       end
869     end
870     subclass.instance_variable_set(iv, sup_class_value)
871   end
872 
873   unless ivs.include?(:@dataset)
874     if @dataset && self != Model
875       subclass.set_dataset(@dataset.clone, :inherited=>true)
876     elsif (n = subclass.name) && !n.to_s.empty?
877       db
878       subclass.set_dataset(subclass.implicit_table_name)
879     end
880   end
881 end
inherited_instance_variables() click to toggle source

A hash of instance variables to automatically set up in subclasses. Keys are instance variable symbols, values should be:

nil

Assign directly from superclass to subclass (frozen objects)

:dup

Dup object when assigning from superclass to subclass (mutable objects)

:hash_dup

Assign hash with same keys, but dup all the values

Proc

Call with subclass to do the assignment

    # File lib/sequel/model/base.rb
889 def inherited_instance_variables
890   {
891     :@cache_anonymous_models=>nil,
892     :@dataset_method_modules=>:dup,
893     :@dataset_module_class=>nil,
894     :@db=>nil,
895     :@default_set_fields_options=>:dup,
896     :@fast_instance_delete_sql=>nil,
897     :@fast_pk_lookup_sql=>nil,
898     :@plugins=>:dup,
899     :@primary_key=>nil,
900     :@raise_on_save_failure=>nil,
901     :@raise_on_typecast_failure=>nil,
902     :@require_modification=>nil,
903     :@require_valid_table=>nil,
904     :@restrict_primary_key=>nil,
905     :@setter_methods=>nil,
906     :@simple_pk=>nil,
907     :@simple_table=>nil,
908     :@strict_param_setting=>nil,
909     :@typecast_empty_string_to_nil=>nil,
910     :@typecast_on_assignment=>nil,
911     :@use_transactions=>nil
912   }
913 end
late_binding_class_option(opts, default) click to toggle source

For the given opts hash and default name or :class option, add a :class_name option unless already present which contains the name of the class to use as a string. The purpose is to allow late binding to the class later using constantize.

    # File lib/sequel/model/base.rb
919 def late_binding_class_option(opts, default)
920   case opts[:class]
921     when String, Symbol
922       # Delete :class to allow late binding
923       class_name = opts.delete(:class).to_s
924 
925       if (namespace = opts[:class_namespace]) && !class_name.start_with?('::')
926         class_name = "::#{namespace}::#{class_name}"
927       end
928 
929       opts[:class_name] ||= class_name
930     when Class
931       opts[:class_name] ||= opts[:class].name
932   end
933 
934   opts[:class_name] ||= '::' + ((name || '').split("::")[0..-2] + [camelize(default)]).join('::')
935 end
method_added(meth) click to toggle source

Clear the setter_methods cache when a setter method is added.

Calls superclass method
    # File lib/sequel/model/base.rb
938 def method_added(meth)
939   clear_setter_methods_cache if meth.to_s.end_with?('=')
940   super
941 end
overridable_methods_module() click to toggle source

Module that the class includes that holds methods the class adds for column accessors and associations so that the methods can be overridden with super.

    # File lib/sequel/model/base.rb
945 def overridable_methods_module
946   include(@overridable_methods_module = Module.new) unless @overridable_methods_module
947   @overridable_methods_module
948 end
plugin_module(plugin) click to toggle source

Returns the module for the specified plugin. If the module is not defined, the corresponding plugin required.

    # File lib/sequel/model/base.rb
952 def plugin_module(plugin)
953   module_name = plugin.to_s.gsub(/(^|_)(.)/){|x| x[-1..-1].upcase}
954   unless Sequel::Plugins.const_defined?(module_name, false)
955     require "sequel/plugins/#{plugin}"
956   end
957   Sequel::Plugins.const_get(module_name)
958 end
primary_key_lookup(pk) click to toggle source

Find the row in the dataset that matches the primary key. Uses a static SQL optimization if the table and primary key are simple.

This method should not be called with a nil primary key, in case it is overridden by plugins which assume that the passed argument is valid.

    # File lib/sequel/model/base.rb
966 def primary_key_lookup(pk)
967   if sql = @fast_pk_lookup_sql
968     sql = sql.dup
969     ds = dataset
970     ds.literal_append(sql, pk)
971     ds.fetch_rows(sql){|r| return ds.row_proc.call(r)}
972     nil
973   else
974     dataset.first(primary_key_hash(pk))
975   end
976 end
reload_db_schema?() click to toggle source

Whether to reload the database schema by default, ignoring any cached value.

    # File lib/sequel/model/base.rb
979 def reload_db_schema?
980   false
981 end
reset_fast_pk_lookup_sql() click to toggle source

Reset the cached fast primary lookup SQL if a simple table and primary key are used, or set it to nil if not used.

    # File lib/sequel/model/base.rb
985 def reset_fast_pk_lookup_sql
986   @fast_pk_lookup_sql = if @simple_table && @simple_pk
987     "SELECT * FROM #{@simple_table} WHERE #{@simple_pk} = ".freeze
988   end
989   @fast_instance_delete_sql = if @simple_table && @simple_pk
990     "DELETE FROM #{@simple_table} WHERE #{@simple_pk} = ".freeze
991   end
992 end
reset_instance_dataset() click to toggle source

Reset the instance dataset to a modified copy of the current dataset, should be used whenever the model’s dataset is modified.

    # File lib/sequel/model/base.rb
996 def reset_instance_dataset
997   @instance_dataset = @dataset.limit(1).naked.skip_limit_check if @dataset
998 end
set_columns(new_columns) click to toggle source

Set the columns for this model and create accessor methods for each column.

     # File lib/sequel/model/base.rb
1001 def set_columns(new_columns)
1002   @columns = new_columns
1003   def_column_accessor(*new_columns) if new_columns
1004   @columns
1005 end
set_dataset_row_proc(ds) click to toggle source

Set the dataset’s row_proc to the current model.

     # File lib/sequel/model/base.rb
1008 def set_dataset_row_proc(ds)
1009   ds.with_row_proc(self)
1010 end
simple_pk=(pk) click to toggle source

Reset the fast primary key lookup SQL when the simple_pk value changes.

     # File lib/sequel/model/base.rb
1013 def simple_pk=(pk)
1014   @simple_pk = pk
1015   reset_fast_pk_lookup_sql
1016 end
simple_table=(t) click to toggle source

Reset the fast primary key lookup SQL when the simple_table value changes.

     # File lib/sequel/model/base.rb
1019 def simple_table=(t)
1020   @simple_table = t
1021   reset_fast_pk_lookup_sql
1022 end