# 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
module Sequel::Model::ClassMethods
Class methods for Sequel::Model
that implement basic model functionality.
-
All of the following methods have class methods created that send the method to the model’s dataset: all, as_hash, avg, count, cross_join, distinct, each, each_server, empty?, except, exclude, exclude_having, fetch_rows, filter, first, first!, for_update, from, from_self, full_join, full_outer_join, get, graph, grep, group, group_and_count, group_append, group_by, having, import, inner_join, insert, intersect, invert, join, join_table, last, left_join, left_outer_join, limit, lock_style, map, max, min, multi_insert, naked, natural_full_join, natural_join, natural_left_join, natural_right_join, offset, order, order_append, order_by, order_more, order_prepend, paged_each, qualify, reverse, reverse_order, right_join, right_outer_join, select, select_all, select_append, select_group, select_hash, select_hash_groups, select_map, select_more, select_order_map, select_prepend, server, single_record, single_record!, single_value, single_value!, sum, to_hash, to_hash_groups, truncate, unfiltered, ungraphed, ungrouped, union, unlimited, unordered, where, where_all, where_each, where_single_value, with, with_recursive, with_sql
Attributes
Whether to cache the anonymous models created by Sequel::Model(), true by default. This is required for reloading them correctly (avoiding the superclass mismatch).
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.
The Module subclass to use for dataset_module
blocks.
The default options to use for Model#set_fields. These are merged with the options given to set_fields.
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.
SQL
string fragment used for faster lookups by primary key, or nil if the optimization should not be used. For internal use only.
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.
Array
of plugin modules loaded by this class
Sequel::Model.plugins # => [Sequel::Model, Sequel::Model::Associations]
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.
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).
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.
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).
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.
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.
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.[].
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.
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.
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.
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
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 theDatabase
insource
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
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
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 the setter_methods
cache
# File lib/sequel/model/base.rb 228 def clear_setter_methods_cache 229 @setter_methods = nil unless frozen? 230 end
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
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
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
Alias of set_dataset
# File lib/sequel/model/base.rb 268 def dataset=(ds) 269 set_dataset(ds) 270 end
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
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
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
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
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
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
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
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 a model class, disallowing any further changes to it.
# 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
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
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
Clear the setter_methods
cache when a module is included, as it may contain setter methods.
# File lib/sequel/model/base.rb 458 def include(*mods) 459 clear_setter_methods_cache 460 super 461 end
Calls call
with the values hash.
# File lib/sequel/model/base.rb 473 def load(values) 474 call(values) 475 end
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
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
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}
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 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
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
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
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
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
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
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
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
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
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 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
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
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
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
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 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 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
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
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
# 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
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
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
Clear the setter_methods
cache when a setter method is added.
# 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
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
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
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
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 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 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 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 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
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