couchrest_model/lib/couchrest/model/persistence.rb
2011-05-31 16:31:37 -06:00

169 lines
5.3 KiB
Ruby

module CouchRest
module Model
module Persistence
extend ActiveSupport::Concern
# Create the document. Validation is enabled by default and will return
# false if the document is not valid. If all goes well, the document will
# be returned.
def create(options = {})
return false unless perform_validations(options)
_run_create_callbacks do
_run_save_callbacks do
set_unique_id if new? && self.respond_to?(:set_unique_id)
result = database.save_doc(self)
ret = (result["ok"] == true) ? self : false
@changed_attributes.clear if ret && @changed_attributes
ret
end
end
end
# Creates the document in the db. Raises an exception
# if the document is not created properly.
def create!(options = {})
self.class.fail_validate!(self) unless self.create(options)
end
# Trigger the callbacks (before, after, around)
# only if the document isn't new
def update(options = {})
raise "Calling #{self.class.name}#update on document that has not been created!" if self.new?
return false unless perform_validations(options)
return true if !self.disable_dirty && !self.changed?
_run_update_callbacks do
_run_save_callbacks do
result = database.save_doc(self)
ret = result["ok"] == true
@changed_attributes.clear if ret && @changed_attributes
ret
end
end
end
# Trigger the callbacks (before, after, around) and save the document
def save(options = {})
self.new? ? create(options) : update(options)
end
# Saves the document to the db using save. Raises an exception
# if the document is not saved properly.
def save!
self.class.fail_validate!(self) unless self.save
true
end
# Deletes the document from the database. Runs the :destroy callbacks.
# Removes the <tt>_id</tt> and <tt>_rev</tt> fields, preparing the
# document to be saved to a new <tt>_id</tt> if required.
def destroy
_run_destroy_callbacks do
result = database.delete_doc(self)
if result['ok']
self.delete('_rev')
self.delete('_id')
end
result['ok']
end
end
# Update the document's attributes and save. For example:
#
# doc.update_attributes :name => "Fred"
# Is the equivilent of doing the following:
#
# doc.attributes = { :name => "Fred" }
# doc.save
#
def update_attributes(hash)
update_attributes_without_saving hash
save
end
# Reloads the attributes of this object from the database.
# It doesn't override custom instance variables.
#
# Returns self.
def reload
merge!(self.class.get(id))
self
end
protected
def perform_validations(options = {})
perform_validation = case options
when Hash
options[:validate] != false
else
options
end
perform_validation ? valid? : true
end
module ClassMethods
# Creates a new instance, bypassing attribute protection
#
# ==== Returns
# a document instance
#
def build_from_database(doc = {})
base = (doc[model_type_key].blank? || doc[model_type_key] == self.to_s) ? self : doc[model_type_key].constantize
base.new(doc, :directly_set_attributes => true)
end
# Defines an instance and save it directly to the database
#
# ==== Returns
# returns the reloaded document
def create(attributes = {}, &block)
instance = new(attributes, &block)
instance.create
instance
end
# Defines an instance and save it directly to the database
#
# ==== Returns
# returns the reloaded document or raises an exception
def create!(attributes = {}, &block)
instance = new(attributes, &block)
instance.create!
instance
end
# Name a method that will be called before the document is first saved,
# which returns a string to be used for the document's <tt>_id</tt>.
#
# Because CouchDB enforces a constraint that each id must be unique,
# this can be used to enforce eg: uniq usernames. Note that this id
# must be globally unique across all document types which share a
# database, so if you'd like to scope uniqueness to this class, you
# should use the class name as part of the unique id.
def unique_id(method = nil, &block)
if method
define_method :set_unique_id do
self['_id'] ||= self.send(method)
end
elsif block
define_method :set_unique_id do
uniqid = block.call(self)
raise ArgumentError, "unique_id block must not return nil" if uniqid.nil?
self['_id'] ||= uniqid
end
end
end
# Raise an error if validation failed.
def fail_validate!(document)
raise Errors::Validations.new(document)
end
end
end
end
end