1.7.0

1.7.0

Released: August 30, 2021

changed

• [changed] [installation] Alembic 1.7 now supports Python 3.6 and above; support for prior versions
  including Python 2.7 has been dropped.

• [changed] [installation] Make the python-dateutil library an optional dependency.
  This library is only required if the timezone option
  is used in the Alembic configuration.
  An extra require named tz is available with
  pip install alembic[tz] to install it.

  References: #674

• [changed] [installation] The dependency on pkg_resources which is part of setuptools has
  been removed, so there is no longer any runtime dependency on
  setuptools. The functionality has been replaced with
  importlib.metadata and importlib.resources which are both part of
  Python std.lib, or via pypy dependency importlib-metadata for Python
  version < 3.8 and importlib-resources for Python version < 3.9
  (while importlib.resources was added to Python in 3.7, it did not include
  the "files" API until 3.9).

  References: #885

feature

• [feature] [environment] Enhance version_locations parsing to handle paths containing spaces.
  The new configuration option version_path_separator specifies the
  character to use when splitting the version_locations string. The
  default for new configurations is version_path_separator = os,
  which will use os.pathsep (e.g., ; on Windows).

  References: #842

• [feature] [tests] Created a "test suite" similar to the one for SQLAlchemy, allowing
  developers of third-party dialects to test their code against a set of
  Alembic tests that have been specially selected to exercise
  back-end database operations. At the time of release,
  third-party dialects that have adopted the Alembic test suite to verify
  compatibility include
  CockroachDB and
  SAP ASE (Sybase).

  References: #855

• [feature] [general] pep-484 type annotations have been added throughout the library.
  Additionally, stub .pyi files have been added for the "dynamically"
  generated Alembic modules alembic.op and alembic.config, which
  include complete function signatures and docstrings, so that the functions
  in these namespaces will have both IDE support (vscode, pycharm, etc) as
  well as support for typing tools like Mypy. The files themselves are
  statically generated from their source functions within the source tree.

usecase

• [usecase] [batch] Named CHECK constraints are now supported by batch mode, and will
  automatically be part of the recreated table assuming they are named. They
  also can be explicitly dropped using op.drop_constraint(). For
  "unnamed" CHECK constraints, these are still skipped as they cannot be
  distinguished from the CHECK constraints that are generated by the
  Boolean and Enum datatypes.

  Note that this change may require adjustments to migrations that drop or
  rename columns which feature an associated named check constraint, such
  that an additional op.drop_constraint() directive should be added for
  that named constraint as there will no longer be an associated column
  for it; for the Boolean and Enum datatypes, an existing_type
  keyword may be passed to BatchOperations.drop_constraint as well.

  References: #884

bug

• [bug] [operations] Fixed regression due to #803 where the .info and .comment
  attributes of Table would be lost inside of the DropTableOp
  class, which when "reversed" into a CreateTableOp would then have
  lost these elements. Pull request courtesy Nicolas CANIART.

  References: #879

• [bug] [batch] [sqlite] Batch "auto" mode will now select for "recreate" if the add_column()
  operation is used on SQLite, and the column itself meets the criteria for
  SQLite where ADD COLUMN is not allowed, in this case a functional or
  parenthesized SQL expression or a Computed (i.e. generated) column.

  References: #883

• [bug] [commands] Re-implemented the python-editor dependency as a small internal
  function to avoid the need for external dependencies.

  References: #856

• [bug] [postgresql] Fixed issue where usage of the PostgreSQL postgresql_include option
  within a Operations.create_index() would raise a KeyError, as the
  additional column(s) need to be added to the table object used by the
  construct internally. The issue is equivalent to the SQL Server issue fixed
  in #513. Pull request courtesy Steven Bronson.

  References: #874

1.6.5

1.6.5

Released: May 27, 2021

bug

• [bug] [autogenerate] Fixed issue where dialect-specific keyword arguments within the
  DropIndex operation directive would not render in the
  autogenerated Python code. As support was improved for adding dialect
  specific arguments to directives as part of #803, in particular
  arguments such as "postgresql_concurrently" which apply to the actual
  create/drop of the index, support was needed for these to render even in a
  drop index operation. Pull request courtesy Jet Zhou.

  References: #849

1.6.4

1.6.4

Released: May 24, 2021

bug

• [bug] [op directives] [regression] Fixed regression caused by just fixed #844 that scaled back the
  filter for unique=True/index=True too far such that these directives no
  longer worked for the op.create_table() op, this has been fixed.

  References: #848

1.6.3

1.6.3

Released: May 21, 2021

bug

• [bug] [autogenerate] [regression] Fixed 1.6-series regression where UniqueConstraint and to a lesser
  extent Index objects would be doubled up in the generated model when
  the unique=True / index=True flags were used.

  References: #844

• [bug] [autogenerate] Fixed a bug where paths defined in post-write hook options
  would be wrongly escaped in non posix environment (Windows).

  References: #839

• [bug] [regression] [versioning] Fixed regression where a revision file that contained its own down revision
  as a dependency would cause an endless loop in the traversal logic.

  References: #843

1.6.2

1.6.2

Released: May 6, 2021

bug

• [bug] [regression] [versioning] Fixed additional regression nearly the same as that of #838 just
  released in 1.6.1 but within a slightly different codepath, where "alembic
  downgrade head" (or equivalent) would fail instead of iterating no
  revisions.

  References: #839

1.6.1

1.6.1

Released: May 6, 2021

bug

• [bug] [regression] [versioning] Fixed regression in new revisioning traversal where "alembic downgrade
  base" would fail if the database itself were clean and unversioned;
  additionally repairs the case where downgrade would fail if attempting
  to downgrade to the current head that is already present.

  References: #838

1.6.0

1.6.0

Released: May 3, 2021

feature

• [feature] [autogenerate] Fix the documentation regarding the default command-line argument position of
  the revision script filename within the post-write hook arguments. Implement a
  REVISION_SCRIPT_FILENAME token, enabling the position to be changed. Switch
  from str.split() to shlex.split() for more robust command-line argument
  parsing.

  References: #819

• [feature] Implement a .cwd (current working directory) suboption for post-write hooks
  (of type console_scripts). This is useful for tools like pre-commit, which
  rely on the working directory to locate the necessary config files. Add
  pre-commit as an example to the documentation. Minor change: rename some variables
  from ticket #819 to improve readability.

  References: #822

bug

• [bug] [autogenerate] Refactored the implementation of MigrateOperation constructs such
  as CreateIndexOp, CreateTableOp, etc. so that they no
  longer rely upon maintaining a persistent version of each schema object
  internally; instead, the state variables of each operation object will be
  used to produce the corresponding construct when the operation is invoked.
  The rationale is so that environments which make use of
  operation-manipulation schemes such as those those discussed in
  autogen_rewriter are better supported, allowing end-user code to
  manipulate the public attributes of these objects which will then be
  expressed in the final output, an example is
  some_create_index_op.kw["postgresql_concurrently"] = True.

  Previously, these objects when generated from autogenerate would typically
  hold onto the original, reflected element internally without honoring the
  other state variables of each construct, preventing the public API from
  working.

  References: #803

• [bug] [environment] Fixed regression caused by the SQLAlchemy 1.4/2.0 compatibility switch
  where calling .rollback() or .commit() explicitly within the
  context.begin_transaction() context manager would cause it to fail when
  the block ended, as it did not expect that the transaction was manually
  closed.

  References: #829

• [bug] [autogenerate] Improved the rendering of op.add_column() operations when adding
  multiple columns to an existing table, so that the order of these
  statements matches the order in which the columns were declared in the
  application's table metadata. Previously the added columns were being
  sorted alphabetically.

  References: #827

• [bug] [versioning] The algorithm used for calculating downgrades/upgrades/iterating
  revisions has been rewritten, to resolve ongoing issues of branches
  not being handled consistently particularly within downgrade operations,
  as well as for overall clarity and maintainability. This change includes
  that a deprecation warning is emitted if an ambiguous command such
  as "downgrade -1" when multiple heads are present is given.

  In particular, the change implements a long-requested use case of allowing
  downgrades of a single branch to a branchpoint.

  Huge thanks to Simon Bowly for their impressive efforts in successfully
  tackling this very difficult problem.

  References: #464, #765

• [bug] [batch] Added missing batch_op.create_table_comment(),
  batch_op.drop_table_comment() directives to batch ops.

  References: #799

1.5.8

1.5.8

Released: March 23, 2021

bug

• [bug] [environment] Fixed regression caused by SQLAlchemy 1.4 where the "alembic current"
  command would fail due to changes in the URL object.

  References: #816

1.5.7

1.5.7

Released: March 11, 2021

bug

• [bug] [autogenerate] Adjusted the recently added
  EnvironmentContext.configure.include_name hook to accommodate
  for additional object types such as "views" that don't have a parent table,
  to support third party recipes and extensions. Pull request courtesy Oliver
  Rice.

  References: #813

1.5.6

1.5.6

Released: March 5, 2021

bug

• [bug] [mssql] [operations] Fixed bug where the "existing_type" parameter, which the MSSQL dialect
  requires in order to change the nullability of a column in the absence of
  also changing the column type, would cause an ALTER COLUMN operation to
  incorrectly render a second ALTER statement without the nullability if a
  new type were also present, as the MSSQL-specific contract did not
  anticipate all three of "nullability", "type_" and "existing_type" being
  sent at the same time.

  References: #812

misc

• [template] Add async template to Alembic to bootstrap environments that use
  async DBAPI. Updated the cookbook to include a migration guide
  on how to adapt an existing enviroment for use with DBAPI drivers.