A barebones session store which duck-types with the default session store but bypasses Active Record and issues SQL directly. This is an example session model class meant as a basis for your own classes.

The database connection, table name, and session id and data columns are configurable class attributes. Marshaling and unmarshaling are implemented as class methods that you may override. By default, marshaling data is

ActiveSupport::Base64.encode64(Marshal.dump(data))

and unmarshaling data is

Marshal.load(ActiveSupport::Base64.decode64(data))

This marshaling behavior is intended to store the widest range of binary session data in a text column. For higher performance, store in a blob column instead and forgo the Base64 encoding.

Methods
Attributes
[R] session_id
[R] new_record
[R] new_record?
[W] data
Public Class methods
connection

Use the ActiveRecord::Base.connection by default.

[ show source ]

  # File activerecord/lib/active_record/session_store.rb, line 183
cattr_accessor :connection
data_column

The data field defaults to ‘data’.

This method is also aliased as data_column_name

[ show source ]

  # File activerecord/lib/active_record/session_store.rb, line 200
cattr_accessor :data_column
find_by_session_id(session_id)

Look up a session by id and unmarshal its data if found.

[ show source ]

  # File activerecord/lib/active_record/session_store.rb, line 212
def find_by_session_id(session_id)
  if record = connection.select_one("SELECT * FROM #{@@table_name} WHERE #{@@session_id_column}=#{connection.quote(session_id)}")
    new(:session_id => session_id, :marshaled_data => record['data'])
  end
end
new(attributes)

Look for normal and marshaled data, self.find_by_session_id’s way of telling us to postpone unmarshaling until the data is requested. We need to handle a normal data attribute in case of a new record.

[ show source ]

  # File activerecord/lib/active_record/session_store.rb, line 227
def initialize(attributes)
  @session_id     = attributes[:session_id]
  @data           = attributes[:data]
  @marshaled_data = attributes[:marshaled_data]
  @new_record     = @marshaled_data.nil?
end
session_id_column

The session id field defaults to ‘session_id’.

[ show source ]

  # File activerecord/lib/active_record/session_store.rb, line 194
cattr_accessor :session_id_column
table_name

The table name defaults to ‘sessions’.

[ show source ]

  # File activerecord/lib/active_record/session_store.rb, line 188
cattr_accessor :table_name
Public Instance methods
data()

Lazy-unmarshal session state.

[ show source ]

  # File activerecord/lib/active_record/session_store.rb, line 235
def data
  unless @data
    if @marshaled_data
      @data, @marshaled_data = self.class.unmarshal(@marshaled_data) || {}, nil
    else
      @data = {}
    end
  end
  @data
end
destroy()

[ show source ]

  # File activerecord/lib/active_record/session_store.rb, line 274
def destroy
  return if @new_record

  connect = connection
  connect.delete           DELETE FROM #{table_name}          WHERE #{connect.quote_column_name(session_id_column)}=#{connect.quote(session_id)}, 'Destroy session'
end
loaded?()

[ show source ]

  # File activerecord/lib/active_record/session_store.rb, line 246
def loaded?
  @data
end
save()

[ show source ]

  # File activerecord/lib/active_record/session_store.rb, line 250
def save
  return false unless loaded?
  marshaled_data = self.class.marshal(data)
  connect        = connection

  if @new_record
    @new_record = false
    connect.update             INSERT INTO #{table_name} (              #{connect.quote_column_name(session_id_column)},              #{connect.quote_column_name(data_column)} )            VALUES (              #{connect.quote(session_id)},              #{connect.quote(marshaled_data)} ), 'Create session'
  else
    connect.update             UPDATE #{table_name}            SET #{connect.quote_column_name(data_column)}=#{connect.quote(marshaled_data)}            WHERE #{connect.quote_column_name(session_id_column)}=#{connect.quote(session_id)}, 'Update session'
  end
end