Datamapper DataMapper → 0.10.2

Json type fails migration with the following error:

 ~ Column length too big for column 'data' (max = 21845); use BLOB or TEXT instead (code: 1074, sql state: 42000, query: CREATE TABLE "temp_payments" ("session_id" VARCHAR(32) NOT NULL, "data" VARCHAR(65535), "created_at" DATETIME NOT NULL, "updated_at" DATETIME NOT NULL, PRIMARY KEY("session_id")) ENGINE = InnoDB CHARACTER SET utf8 COLLATE utf8_general_ci, uri: mysql://root@localhostcyr_dev?socket=/tmp/mysql.sock)
rake aborted!
Column length too big for column 'data' (max = 21845); use BLOB or TEXT instead
/opt/local/lib/ruby/gems/1.8/gems/dm-core-0.10.0/lib/dm-core/migrations.rb:151:in execute_non_query'
/opt/local/lib/ruby/gems/1.8/gems/dm-core-0.10.0/lib/dm-core/migrations.rb:151:increate_model_storage'
/opt/local/lib/ruby/gems/1.8/gems/dm-core-0.10.0/lib/dm-core/adapters/data_objects_adapter.rb:263:in with_connection'
/opt/local/lib/ruby/gems/1.8/gems/dm-core-0.10.0/lib/dm-core/migrations.rb:148:increate_model_storage'
/opt/local/lib/ruby/gems/1.8/gems/dm-core-0.10.0/lib/dm-core/migrations.rb:669:in create_model_storage'
/opt/local/lib/ruby/gems/1.8/gems/dm-core-0.10.0/lib/dm-core/migrations.rb:769:inauto_migrate_up!'
/opt/local/lib/ruby/gems/1.8/gems/dm-core-0.10.0/lib/dm-core/migrations.rb:51:in send'
/opt/local/lib/ruby/gems/1.8/gems/dm-core-0.10.0/lib/dm-core/migrations.rb:51:inrepository_execute'

Sample model:

class Book
  property :json_data, Json
end

Tried this patch, but it DID NOT WORK.

# dm-types-0.10.0/lib/dm-types/json.rb







module DataMapper
  module Types

class Json < DataMapper::Types::Text
  #primitive String
  #length    65535
  #lazy      true

  ...</code>

Attempted patch resulted in:

+type+ was DataMapper::Types::Json, which is not a supported type
/opt/local/lib/ruby/gems/1.8/gems/dm-core-0.10.0/lib/dm-core/property.rb:815:in initialize'
/opt/local/lib/ruby/gems/1.8/gems/dm-core-0.10.0/lib/dm-core/model/property.rb:55:innew'
/opt/local/lib/ruby/gems/1.8/gems/dm-core-0.10.0/lib/dm-core/model/property.rb:55:in property'</code>
</pre>