class ActionDispatch::Session::ActiveRecordStore
Active Record Session Store¶ ↑
A session store backed by an Active Record class. A default class is
provided, but any object duck-typing to an Active Record Session class with text session_id
and data
attributes is sufficient.
The default assumes a sessions
tables with columns:
+id+ (numeric primary key), +session_id+ (string, usually varchar; maximum length is 255), and +data+ (text or longtext; careful if your session data exceeds 65KB).
The session_id
column should always be indexed for speedy
lookups. Session data is marshaled to the
data
column in Base64 format. If the data you write is larger
than the column's size limit, ActionController::SessionOverflowError
will be raised.
You may configure the table name, primary key, and data column. For
example, at the end of config/application.rb
:
ActiveRecord::SessionStore::Session.table_name = 'legacy_session_table' ActiveRecord::SessionStore::Session.primary_key = 'session_id' ActiveRecord::SessionStore::Session.data_column_name = 'legacy_session_data'
Note that setting the primary key to the session_id
frees you
from having a separate id
column if you don't want it.
However, you must set session.model.id = session.session_id
by
hand! A before filter on ApplicationController is a good place.
Since the default class is a simple Active Record, you get timestamps for
free if you add created_at
and updated_at
datetime columns to the sessions
table, making periodic
session expiration a snap.
You may provide your own session class implementation, whether a feature-packed Active Record or a bare-metal high-performance SQL store, by setting
ActionDispatch::Session::ActiveRecordStore.session_class = MySessionClass
You must implement these methods:
self.find_by_session_id(session_id) initialize(hash_of_session_id_and_data, options_hash = {}) attr_reader :session_id attr_accessor :data save destroy
The example SqlBypass class is a generic SQL session store. You may use it as a basis for high-performance database-specific stores.
Constants
- ENV_SESSION_OPTIONS_KEY
- SESSION_RECORD_KEY
Private Instance Methods
# File lib/action_dispatch/session/active_record_store.rb, line 94 def destroy_session(env, session_id, options) logger.silence_logger do if sid = current_session_id(env) get_session_model(env, sid).destroy env[SESSION_RECORD_KEY] = nil end generate_sid unless options[:drop] end end
# File lib/action_dispatch/session/active_record_store.rb, line 113 def find_session(id) @@session_class.find_by_session_id(id) || @@session_class.new(:session_id => id, :data => {}) end
# File lib/action_dispatch/session/active_record_store.rb, line 64 def get_session(env, sid) logger.silence_logger do unless sid and session = @@session_class.find_by_session_id(sid) # If the sid was nil or if there is no pre-existing session under the sid, # force the generation of a new sid and associate a new session associated with the new sid sid = generate_sid session = @@session_class.new(:session_id => sid, :data => {}) end env[SESSION_RECORD_KEY] = session [sid, session.data] end end
# File lib/action_dispatch/session/active_record_store.rb, line 105 def get_session_model(env, sid) if env[ENV_SESSION_OPTIONS_KEY][:id].nil? env[SESSION_RECORD_KEY] = find_session(sid) else env[SESSION_RECORD_KEY] ||= find_session(sid) end end
# File lib/action_dispatch/session/active_record_store.rb, line 118 def logger ActiveRecord::Base.logger || ActiveRecord::SessionStore::NilLogger end
# File lib/action_dispatch/session/active_record_store.rb, line 77 def set_session(env, sid, session_data, options) logger.silence_logger do record = get_session_model(env, sid) record.data = session_data return false unless record.save session_data = record.data if session_data && session_data.respond_to?(:each_value) session_data.each_value do |obj| obj.clear_association_cache if obj.respond_to?(:clear_association_cache) end end sid end end