1.2.3

Released: February 16, 2018

• [bug] [postgresql] Added "SSL SYSCALL error: Operation timed out" to the list
  of messages that trigger a "disconnect" scenario for the
  psycopg2 driver. Pull request courtesy André Cruz.

  This change is also backported to: 1.1.16

• [bug] [orm] Fixed issue in post_update feature where an UPDATE is emitted
  when the parent object has been deleted but the dependent object
  is not. This issue has existed for a long time however
  since 1.2 now asserts rows matched for post_update, this
  was raising an error.

  This change is also backported to: 1.1.16

  References: #4187

• [bug] [orm] Fixed regression caused by fix for issue #4116 affecting versions
  1.2.2 as well as 1.1.15, which had the effect of mis-calculation of the
  "owning class" of an AssociationProxy as the NoneType class
  in some declarative mixin/inheritance situations as well as if the
  association proxy were accessed off of an un-mapped class. The "figure out
  the owner" logic has been replaced by an in-depth routine that searches
  through the complete mapper hierarchy assigned to the class or subclass to
  determine the correct (we hope) match; will not assign the owner if no
  match is found. An exception is now raised if the proxy is used
  against an un-mapped instance.

  This change is also backported to: 1.1.16

  References: #4185

• [bug] [postgresql] Added "TRUNCATE" to the list of keywords accepted by the
  PostgreSQL dialect as an "autocommit"-triggering keyword.
  Pull request courtesy Jacob Hayes.

  This change is also backported to: 1.1.16

• [bug] [pool] Fixed a fairly serious connection pool bug where a connection that is
  acquired after being refreshed as a result of a user-defined
  DisconnectionError or due to the 1.2-released "pre_ping" feature
  would not be correctly reset if the connection were returned to the pool by
  weakref cleanup (e.g. the front-facing object is garbage collected); the
  weakref would still refer to the previously invalidated DBAPI connection
  which would have the reset operation erroneously called upon it instead.
  This would lead to stack traces in the logs and a connection being checked
  into the pool without being reset, which can cause locking issues.

  This change is also backported to: 1.1.16

  References: #4184

• [bug] [oracle] Fixed bug in cx_Oracle disconnect detection, used by pre_ping and other
  features, where an error could be raised as DatabaseError which includes a
  numeric error code; previously we weren't checking in this case for a
  disconnect code.

  References: #4182

• [bug] [sqlite] Fixed the import error raised when a platform
  has neither pysqlite2 nor sqlite3 installed, such
  that the sqlite3-related import error is raised,
  not the pysqlite2 one which is not the actual
  failure mode. Pull request courtesy Robin.

• [bug] [orm] Fixed bug where the Bundle object did not
  correctly report upon the primary Mapper object
  represented by the bundle, if any. An immediate
  side effect of this issue was that the new selectinload
  loader strategy wouldn't work with the horizontal sharding
  extension.

  References: #4175

• [bug] [sql] Fixed bug where the Enum type wouldn't handle
  enum "aliases" correctly, when more than one key refers to the
  same value. Pull request courtesy Daniel Knell.

  References: #4180

• [bug] [engine] Fixed bug where events associated with an Engine
  at the class level would be doubled when the
  Engine.execution_options() method were used. To
  achieve this, the semi-private class OptionEngine
  no longer accepts events directly at the class level
  and will raise an error; the class only propagates class-level
  events from its parent Engine. Instance-level
  events continue to work as before.

  References: #4181

• [bug] [tests] A test added in 1.2 thought to confirm a Python 2.7 behavior turns out to
  be confirming the behavior only as of Python 2.7.8. Python bug #8743 still
  impacts set comparison in Python 2.7.7 and earlier, so the test in question
  involving AssociationSet no longer runs for these older Python 2.7
  versions.

  References: #3265

• [feature] [oracle] The ON DELETE options for foreign keys are now part of
  Oracle reflection. Oracle does not support ON UPDATE
  cascades. Pull request courtesy Miroslav Shubernetskiy.

• [bug] [orm] Fixed bug in concrete inheritance mapping where user-defined
  attributes such as hybrid properties that mirror the names
  of mapped attributes from sibling classes would be overwritten by
  the mapper as non-accessible at the instance level. Additionally
  ensured that user-bound descriptors are not implicitly invoked at the class
  level during the mapper configuration stage.

  References: #4188

• [bug] [orm] Fixed bug where the orm.reconstructor() event
  helper would not be recognized if it were applied to the
  __init__() method of the mapped class.

  References: #4178

• [bug] [engine] The URL object now allows query keys to be specified multiple
  times where their values will be joined into a list. This is to support
  the plugins feature documented at CreateEnginePlugin which
  documents that "plugin" can be passed multiple times. Additionally, the
  plugin names can be passed to create_engine() outside of the URL
  using the new create_engine.plugins parameter.

  References: #4170

• [feature] [sql] Added support for Enum to persist the values of the enumeration,
  rather than the keys, when using a Python pep-435 style enumerated object.
  The user supplies a callable function that will return the string values to
  be persisted. This allows enumerations against non-string values to be
  value-persistable as well. Pull request courtesy Jon Snyder.

  References: #3906

• [feature] [orm] Added new argument attributes.set_attribute.inititator
  to the attributes.set_attribute() function, allowing an
  event token received from a listener function to be propagated
  to subsequent set events.