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- # ### this file stubs are generated by tools/write_pyi.py - do not edit ###
- # ### imports are manually managed
- from __future__ import annotations
- from typing import Any
- from typing import Callable
- from typing import Collection
- from typing import Dict
- from typing import Iterable
- from typing import List
- from typing import Literal
- from typing import Mapping
- from typing import MutableMapping
- from typing import Optional
- from typing import overload
- from typing import Sequence
- from typing import TextIO
- from typing import Tuple
- from typing import TYPE_CHECKING
- from typing import Union
- from typing_extensions import ContextManager
- if TYPE_CHECKING:
- from sqlalchemy.engine.base import Connection
- from sqlalchemy.engine.url import URL
- from sqlalchemy.sql import Executable
- from sqlalchemy.sql.schema import Column
- from sqlalchemy.sql.schema import FetchedValue
- from sqlalchemy.sql.schema import MetaData
- from sqlalchemy.sql.schema import SchemaItem
- from sqlalchemy.sql.type_api import TypeEngine
- from .autogenerate.api import AutogenContext
- from .config import Config
- from .operations.ops import MigrationScript
- from .runtime.migration import _ProxyTransaction
- from .runtime.migration import MigrationContext
- from .runtime.migration import MigrationInfo
- from .script import ScriptDirectory
- ### end imports ###
- def begin_transaction() -> (
- Union[_ProxyTransaction, ContextManager[None, Optional[bool]]]
- ):
- """Return a context manager that will
- enclose an operation within a "transaction",
- as defined by the environment's offline
- and transactional DDL settings.
- e.g.::
- with context.begin_transaction():
- context.run_migrations()
- :meth:`.begin_transaction` is intended to
- "do the right thing" regardless of
- calling context:
- * If :meth:`.is_transactional_ddl` is ``False``,
- returns a "do nothing" context manager
- which otherwise produces no transactional
- state or directives.
- * If :meth:`.is_offline_mode` is ``True``,
- returns a context manager that will
- invoke the :meth:`.DefaultImpl.emit_begin`
- and :meth:`.DefaultImpl.emit_commit`
- methods, which will produce the string
- directives ``BEGIN`` and ``COMMIT`` on
- the output stream, as rendered by the
- target backend (e.g. SQL Server would
- emit ``BEGIN TRANSACTION``).
- * Otherwise, calls :meth:`sqlalchemy.engine.Connection.begin`
- on the current online connection, which
- returns a :class:`sqlalchemy.engine.Transaction`
- object. This object demarcates a real
- transaction and is itself a context manager,
- which will roll back if an exception
- is raised.
- Note that a custom ``env.py`` script which
- has more specific transactional needs can of course
- manipulate the :class:`~sqlalchemy.engine.Connection`
- directly to produce transactional state in "online"
- mode.
- """
- config: Config
- def configure(
- connection: Optional[Connection] = None,
- url: Union[str, URL, None] = None,
- dialect_name: Optional[str] = None,
- dialect_opts: Optional[Dict[str, Any]] = None,
- transactional_ddl: Optional[bool] = None,
- transaction_per_migration: bool = False,
- output_buffer: Optional[TextIO] = None,
- starting_rev: Optional[str] = None,
- tag: Optional[str] = None,
- template_args: Optional[Dict[str, Any]] = None,
- render_as_batch: bool = False,
- target_metadata: Union[MetaData, Sequence[MetaData], None] = None,
- include_name: Optional[
- Callable[
- [
- Optional[str],
- Literal[
- "schema",
- "table",
- "column",
- "index",
- "unique_constraint",
- "foreign_key_constraint",
- ],
- MutableMapping[
- Literal[
- "schema_name",
- "table_name",
- "schema_qualified_table_name",
- ],
- Optional[str],
- ],
- ],
- bool,
- ]
- ] = None,
- include_object: Optional[
- Callable[
- [
- SchemaItem,
- Optional[str],
- Literal[
- "schema",
- "table",
- "column",
- "index",
- "unique_constraint",
- "foreign_key_constraint",
- ],
- bool,
- Optional[SchemaItem],
- ],
- bool,
- ]
- ] = None,
- include_schemas: bool = False,
- process_revision_directives: Optional[
- Callable[
- [
- MigrationContext,
- Union[str, Iterable[Optional[str]], Iterable[str]],
- List[MigrationScript],
- ],
- None,
- ]
- ] = None,
- compare_type: Union[
- bool,
- Callable[
- [
- MigrationContext,
- Column[Any],
- Column[Any],
- TypeEngine[Any],
- TypeEngine[Any],
- ],
- Optional[bool],
- ],
- ] = True,
- compare_server_default: Union[
- bool,
- Callable[
- [
- MigrationContext,
- Column[Any],
- Column[Any],
- Optional[str],
- Optional[FetchedValue],
- Optional[str],
- ],
- Optional[bool],
- ],
- ] = False,
- render_item: Optional[
- Callable[[str, Any, AutogenContext], Union[str, Literal[False]]]
- ] = None,
- literal_binds: bool = False,
- upgrade_token: str = "upgrades",
- downgrade_token: str = "downgrades",
- alembic_module_prefix: str = "op.",
- sqlalchemy_module_prefix: str = "sa.",
- user_module_prefix: Optional[str] = None,
- on_version_apply: Optional[
- Callable[
- [
- MigrationContext,
- MigrationInfo,
- Collection[Any],
- Mapping[str, Any],
- ],
- None,
- ]
- ] = None,
- **kw: Any,
- ) -> None:
- """Configure a :class:`.MigrationContext` within this
- :class:`.EnvironmentContext` which will provide database
- connectivity and other configuration to a series of
- migration scripts.
- Many methods on :class:`.EnvironmentContext` require that
- this method has been called in order to function, as they
- ultimately need to have database access or at least access
- to the dialect in use. Those which do are documented as such.
- The important thing needed by :meth:`.configure` is a
- means to determine what kind of database dialect is in use.
- An actual connection to that database is needed only if
- the :class:`.MigrationContext` is to be used in
- "online" mode.
- If the :meth:`.is_offline_mode` function returns ``True``,
- then no connection is needed here. Otherwise, the
- ``connection`` parameter should be present as an
- instance of :class:`sqlalchemy.engine.Connection`.
- This function is typically called from the ``env.py``
- script within a migration environment. It can be called
- multiple times for an invocation. The most recent
- :class:`~sqlalchemy.engine.Connection`
- for which it was called is the one that will be operated upon
- by the next call to :meth:`.run_migrations`.
- General parameters:
- :param connection: a :class:`~sqlalchemy.engine.Connection`
- to use
- for SQL execution in "online" mode. When present, is also
- used to determine the type of dialect in use.
- :param url: a string database url, or a
- :class:`sqlalchemy.engine.url.URL` object.
- The type of dialect to be used will be derived from this if
- ``connection`` is not passed.
- :param dialect_name: string name of a dialect, such as
- "postgresql", "mssql", etc.
- The type of dialect to be used will be derived from this if
- ``connection`` and ``url`` are not passed.
- :param dialect_opts: dictionary of options to be passed to dialect
- constructor.
- :param transactional_ddl: Force the usage of "transactional"
- DDL on or off;
- this otherwise defaults to whether or not the dialect in
- use supports it.
- :param transaction_per_migration: if True, nest each migration script
- in a transaction rather than the full series of migrations to
- run.
- :param output_buffer: a file-like object that will be used
- for textual output
- when the ``--sql`` option is used to generate SQL scripts.
- Defaults to
- ``sys.stdout`` if not passed here and also not present on
- the :class:`.Config`
- object. The value here overrides that of the :class:`.Config`
- object.
- :param output_encoding: when using ``--sql`` to generate SQL
- scripts, apply this encoding to the string output.
- :param literal_binds: when using ``--sql`` to generate SQL
- scripts, pass through the ``literal_binds`` flag to the compiler
- so that any literal values that would ordinarily be bound
- parameters are converted to plain strings.
- .. warning:: Dialects can typically only handle simple datatypes
- like strings and numbers for auto-literal generation. Datatypes
- like dates, intervals, and others may still require manual
- formatting, typically using :meth:`.Operations.inline_literal`.
- .. note:: the ``literal_binds`` flag is ignored on SQLAlchemy
- versions prior to 0.8 where this feature is not supported.
- .. seealso::
- :meth:`.Operations.inline_literal`
- :param starting_rev: Override the "starting revision" argument
- when using ``--sql`` mode.
- :param tag: a string tag for usage by custom ``env.py`` scripts.
- Set via the ``--tag`` option, can be overridden here.
- :param template_args: dictionary of template arguments which
- will be added to the template argument environment when
- running the "revision" command. Note that the script environment
- is only run within the "revision" command if the --autogenerate
- option is used, or if the option "revision_environment=true"
- is present in the alembic.ini file.
- :param version_table: The name of the Alembic version table.
- The default is ``'alembic_version'``.
- :param version_table_schema: Optional schema to place version
- table within.
- :param version_table_pk: boolean, whether the Alembic version table
- should use a primary key constraint for the "value" column; this
- only takes effect when the table is first created.
- Defaults to True; setting to False should not be necessary and is
- here for backwards compatibility reasons.
- :param on_version_apply: a callable or collection of callables to be
- run for each migration step.
- The callables will be run in the order they are given, once for
- each migration step, after the respective operation has been
- applied but before its transaction is finalized.
- Each callable accepts no positional arguments and the following
- keyword arguments:
- * ``ctx``: the :class:`.MigrationContext` running the migration,
- * ``step``: a :class:`.MigrationInfo` representing the
- step currently being applied,
- * ``heads``: a collection of version strings representing the
- current heads,
- * ``run_args``: the ``**kwargs`` passed to :meth:`.run_migrations`.
- Parameters specific to the autogenerate feature, when
- ``alembic revision`` is run with the ``--autogenerate`` feature:
- :param target_metadata: a :class:`sqlalchemy.schema.MetaData`
- object, or a sequence of :class:`~sqlalchemy.schema.MetaData`
- objects, that will be consulted during autogeneration.
- The tables present in each :class:`~sqlalchemy.schema.MetaData`
- will be compared against
- what is locally available on the target
- :class:`~sqlalchemy.engine.Connection`
- to produce candidate upgrade/downgrade operations.
- :param compare_type: Indicates type comparison behavior during
- an autogenerate
- operation. Defaults to ``True`` turning on type comparison, which
- has good accuracy on most backends. See :ref:`compare_types`
- for an example as well as information on other type
- comparison options. Set to ``False`` which disables type
- comparison. A callable can also be passed to provide custom type
- comparison, see :ref:`compare_types` for additional details.
- .. versionchanged:: 1.12.0 The default value of
- :paramref:`.EnvironmentContext.configure.compare_type` has been
- changed to ``True``.
- .. seealso::
- :ref:`compare_types`
- :paramref:`.EnvironmentContext.configure.compare_server_default`
- :param compare_server_default: Indicates server default comparison
- behavior during
- an autogenerate operation. Defaults to ``False`` which disables
- server default
- comparison. Set to ``True`` to turn on server default comparison,
- which has
- varied accuracy depending on backend.
- To customize server default comparison behavior, a callable may
- be specified
- which can filter server default comparisons during an
- autogenerate operation.
- defaults during an autogenerate operation. The format of this
- callable is::
- def my_compare_server_default(context, inspected_column,
- metadata_column, inspected_default, metadata_default,
- rendered_metadata_default):
- # return True if the defaults are different,
- # False if not, or None to allow the default implementation
- # to compare these defaults
- return None
- context.configure(
- # ...
- compare_server_default = my_compare_server_default
- )
- ``inspected_column`` is a dictionary structure as returned by
- :meth:`sqlalchemy.engine.reflection.Inspector.get_columns`, whereas
- ``metadata_column`` is a :class:`sqlalchemy.schema.Column` from
- the local model environment.
- A return value of ``None`` indicates to allow default server default
- comparison
- to proceed. Note that some backends such as Postgresql actually
- execute
- the two defaults on the database side to compare for equivalence.
- .. seealso::
- :paramref:`.EnvironmentContext.configure.compare_type`
- :param include_name: A callable function which is given
- the chance to return ``True`` or ``False`` for any database reflected
- object based on its name, including database schema names when
- the :paramref:`.EnvironmentContext.configure.include_schemas` flag
- is set to ``True``.
- The function accepts the following positional arguments:
- * ``name``: the name of the object, such as schema name or table name.
- Will be ``None`` when indicating the default schema name of the
- database connection.
- * ``type``: a string describing the type of object; currently
- ``"schema"``, ``"table"``, ``"column"``, ``"index"``,
- ``"unique_constraint"``, or ``"foreign_key_constraint"``
- * ``parent_names``: a dictionary of "parent" object names, that are
- relative to the name being given. Keys in this dictionary may
- include: ``"schema_name"``, ``"table_name"`` or
- ``"schema_qualified_table_name"``.
- E.g.::
- def include_name(name, type_, parent_names):
- if type_ == "schema":
- return name in ["schema_one", "schema_two"]
- else:
- return True
- context.configure(
- # ...
- include_schemas = True,
- include_name = include_name
- )
- .. seealso::
- :ref:`autogenerate_include_hooks`
- :paramref:`.EnvironmentContext.configure.include_object`
- :paramref:`.EnvironmentContext.configure.include_schemas`
- :param include_object: A callable function which is given
- the chance to return ``True`` or ``False`` for any object,
- indicating if the given object should be considered in the
- autogenerate sweep.
- The function accepts the following positional arguments:
- * ``object``: a :class:`~sqlalchemy.schema.SchemaItem` object such
- as a :class:`~sqlalchemy.schema.Table`,
- :class:`~sqlalchemy.schema.Column`,
- :class:`~sqlalchemy.schema.Index`
- :class:`~sqlalchemy.schema.UniqueConstraint`,
- or :class:`~sqlalchemy.schema.ForeignKeyConstraint` object
- * ``name``: the name of the object. This is typically available
- via ``object.name``.
- * ``type``: a string describing the type of object; currently
- ``"table"``, ``"column"``, ``"index"``, ``"unique_constraint"``,
- or ``"foreign_key_constraint"``
- * ``reflected``: ``True`` if the given object was produced based on
- table reflection, ``False`` if it's from a local :class:`.MetaData`
- object.
- * ``compare_to``: the object being compared against, if available,
- else ``None``.
- E.g.::
- def include_object(object, name, type_, reflected, compare_to):
- if (type_ == "column" and
- not reflected and
- object.info.get("skip_autogenerate", False)):
- return False
- else:
- return True
- context.configure(
- # ...
- include_object = include_object
- )
- For the use case of omitting specific schemas from a target database
- when :paramref:`.EnvironmentContext.configure.include_schemas` is
- set to ``True``, the :attr:`~sqlalchemy.schema.Table.schema`
- attribute can be checked for each :class:`~sqlalchemy.schema.Table`
- object passed to the hook, however it is much more efficient
- to filter on schemas before reflection of objects takes place
- using the :paramref:`.EnvironmentContext.configure.include_name`
- hook.
- .. seealso::
- :ref:`autogenerate_include_hooks`
- :paramref:`.EnvironmentContext.configure.include_name`
- :paramref:`.EnvironmentContext.configure.include_schemas`
- :param render_as_batch: if True, commands which alter elements
- within a table will be placed under a ``with batch_alter_table():``
- directive, so that batch migrations will take place.
- .. seealso::
- :ref:`batch_migrations`
- :param include_schemas: If True, autogenerate will scan across
- all schemas located by the SQLAlchemy
- :meth:`~sqlalchemy.engine.reflection.Inspector.get_schema_names`
- method, and include all differences in tables found across all
- those schemas. When using this option, you may want to also
- use the :paramref:`.EnvironmentContext.configure.include_name`
- parameter to specify a callable which
- can filter the tables/schemas that get included.
- .. seealso::
- :ref:`autogenerate_include_hooks`
- :paramref:`.EnvironmentContext.configure.include_name`
- :paramref:`.EnvironmentContext.configure.include_object`
- :param render_item: Callable that can be used to override how
- any schema item, i.e. column, constraint, type,
- etc., is rendered for autogenerate. The callable receives a
- string describing the type of object, the object, and
- the autogen context. If it returns False, the
- default rendering method will be used. If it returns None,
- the item will not be rendered in the context of a Table
- construct, that is, can be used to skip columns or constraints
- within op.create_table()::
- def my_render_column(type_, col, autogen_context):
- if type_ == "column" and isinstance(col, MySpecialCol):
- return repr(col)
- else:
- return False
- context.configure(
- # ...
- render_item = my_render_column
- )
- Available values for the type string include: ``"column"``,
- ``"primary_key"``, ``"foreign_key"``, ``"unique"``, ``"check"``,
- ``"type"``, ``"server_default"``.
- .. seealso::
- :ref:`autogen_render_types`
- :param upgrade_token: When autogenerate completes, the text of the
- candidate upgrade operations will be present in this template
- variable when ``script.py.mako`` is rendered. Defaults to
- ``upgrades``.
- :param downgrade_token: When autogenerate completes, the text of the
- candidate downgrade operations will be present in this
- template variable when ``script.py.mako`` is rendered. Defaults to
- ``downgrades``.
- :param alembic_module_prefix: When autogenerate refers to Alembic
- :mod:`alembic.operations` constructs, this prefix will be used
- (i.e. ``op.create_table``) Defaults to "``op.``".
- Can be ``None`` to indicate no prefix.
- :param sqlalchemy_module_prefix: When autogenerate refers to
- SQLAlchemy
- :class:`~sqlalchemy.schema.Column` or type classes, this prefix
- will be used
- (i.e. ``sa.Column("somename", sa.Integer)``) Defaults to "``sa.``".
- Can be ``None`` to indicate no prefix.
- Note that when dialect-specific types are rendered, autogenerate
- will render them using the dialect module name, i.e. ``mssql.BIT()``,
- ``postgresql.UUID()``.
- :param user_module_prefix: When autogenerate refers to a SQLAlchemy
- type (e.g. :class:`.TypeEngine`) where the module name is not
- under the ``sqlalchemy`` namespace, this prefix will be used
- within autogenerate. If left at its default of
- ``None``, the ``__module__`` attribute of the type is used to
- render the import module. It's a good practice to set this
- and to have all custom types be available from a fixed module space,
- in order to future-proof migration files against reorganizations
- in modules.
- .. seealso::
- :ref:`autogen_module_prefix`
- :param process_revision_directives: a callable function that will
- be passed a structure representing the end result of an autogenerate
- or plain "revision" operation, which can be manipulated to affect
- how the ``alembic revision`` command ultimately outputs new
- revision scripts. The structure of the callable is::
- def process_revision_directives(context, revision, directives):
- pass
- The ``directives`` parameter is a Python list containing
- a single :class:`.MigrationScript` directive, which represents
- the revision file to be generated. This list as well as its
- contents may be freely modified to produce any set of commands.
- The section :ref:`customizing_revision` shows an example of
- doing this. The ``context`` parameter is the
- :class:`.MigrationContext` in use,
- and ``revision`` is a tuple of revision identifiers representing the
- current revision of the database.
- The callable is invoked at all times when the ``--autogenerate``
- option is passed to ``alembic revision``. If ``--autogenerate``
- is not passed, the callable is invoked only if the
- ``revision_environment`` variable is set to True in the Alembic
- configuration, in which case the given ``directives`` collection
- will contain empty :class:`.UpgradeOps` and :class:`.DowngradeOps`
- collections for ``.upgrade_ops`` and ``.downgrade_ops``. The
- ``--autogenerate`` option itself can be inferred by inspecting
- ``context.config.cmd_opts.autogenerate``.
- The callable function may optionally be an instance of
- a :class:`.Rewriter` object. This is a helper object that
- assists in the production of autogenerate-stream rewriter functions.
- .. seealso::
- :ref:`customizing_revision`
- :ref:`autogen_rewriter`
- :paramref:`.command.revision.process_revision_directives`
- Parameters specific to individual backends:
- :param mssql_batch_separator: The "batch separator" which will
- be placed between each statement when generating offline SQL Server
- migrations. Defaults to ``GO``. Note this is in addition to the
- customary semicolon ``;`` at the end of each statement; SQL Server
- considers the "batch separator" to denote the end of an
- individual statement execution, and cannot group certain
- dependent operations in one step.
- :param oracle_batch_separator: The "batch separator" which will
- be placed between each statement when generating offline
- Oracle migrations. Defaults to ``/``. Oracle doesn't add a
- semicolon between statements like most other backends.
- """
- def execute(
- sql: Union[Executable, str],
- execution_options: Optional[Dict[str, Any]] = None,
- ) -> None:
- """Execute the given SQL using the current change context.
- The behavior of :meth:`.execute` is the same
- as that of :meth:`.Operations.execute`. Please see that
- function's documentation for full detail including
- caveats and limitations.
- This function requires that a :class:`.MigrationContext` has
- first been made available via :meth:`.configure`.
- """
- def get_bind() -> Connection:
- """Return the current 'bind'.
- In "online" mode, this is the
- :class:`sqlalchemy.engine.Connection` currently being used
- to emit SQL to the database.
- This function requires that a :class:`.MigrationContext`
- has first been made available via :meth:`.configure`.
- """
- def get_context() -> MigrationContext:
- """Return the current :class:`.MigrationContext` object.
- If :meth:`.EnvironmentContext.configure` has not been
- called yet, raises an exception.
- """
- def get_head_revision() -> Union[str, Tuple[str, ...], None]:
- """Return the hex identifier of the 'head' script revision.
- If the script directory has multiple heads, this
- method raises a :class:`.CommandError`;
- :meth:`.EnvironmentContext.get_head_revisions` should be preferred.
- This function does not require that the :class:`.MigrationContext`
- has been configured.
- .. seealso:: :meth:`.EnvironmentContext.get_head_revisions`
- """
- def get_head_revisions() -> Union[str, Tuple[str, ...], None]:
- """Return the hex identifier of the 'heads' script revision(s).
- This returns a tuple containing the version number of all
- heads in the script directory.
- This function does not require that the :class:`.MigrationContext`
- has been configured.
- """
- def get_revision_argument() -> Union[str, Tuple[str, ...], None]:
- """Get the 'destination' revision argument.
- This is typically the argument passed to the
- ``upgrade`` or ``downgrade`` command.
- If it was specified as ``head``, the actual
- version number is returned; if specified
- as ``base``, ``None`` is returned.
- This function does not require that the :class:`.MigrationContext`
- has been configured.
- """
- def get_starting_revision_argument() -> Union[str, Tuple[str, ...], None]:
- """Return the 'starting revision' argument,
- if the revision was passed using ``start:end``.
- This is only meaningful in "offline" mode.
- Returns ``None`` if no value is available
- or was configured.
- This function does not require that the :class:`.MigrationContext`
- has been configured.
- """
- def get_tag_argument() -> Optional[str]:
- """Return the value passed for the ``--tag`` argument, if any.
- The ``--tag`` argument is not used directly by Alembic,
- but is available for custom ``env.py`` configurations that
- wish to use it; particularly for offline generation scripts
- that wish to generate tagged filenames.
- This function does not require that the :class:`.MigrationContext`
- has been configured.
- .. seealso::
- :meth:`.EnvironmentContext.get_x_argument` - a newer and more
- open ended system of extending ``env.py`` scripts via the command
- line.
- """
- @overload
- def get_x_argument(as_dictionary: Literal[False]) -> List[str]: ...
- @overload
- def get_x_argument(as_dictionary: Literal[True]) -> Dict[str, str]: ...
- @overload
- def get_x_argument(
- as_dictionary: bool = ...,
- ) -> Union[List[str], Dict[str, str]]:
- """Return the value(s) passed for the ``-x`` argument, if any.
- The ``-x`` argument is an open ended flag that allows any user-defined
- value or values to be passed on the command line, then available
- here for consumption by a custom ``env.py`` script.
- The return value is a list, returned directly from the ``argparse``
- structure. If ``as_dictionary=True`` is passed, the ``x`` arguments
- are parsed using ``key=value`` format into a dictionary that is
- then returned. If there is no ``=`` in the argument, value is an empty
- string.
- .. versionchanged:: 1.13.1 Support ``as_dictionary=True`` when
- arguments are passed without the ``=`` symbol.
- For example, to support passing a database URL on the command line,
- the standard ``env.py`` script can be modified like this::
- cmd_line_url = context.get_x_argument(
- as_dictionary=True).get('dbname')
- if cmd_line_url:
- engine = create_engine(cmd_line_url)
- else:
- engine = engine_from_config(
- config.get_section(config.config_ini_section),
- prefix='sqlalchemy.',
- poolclass=pool.NullPool)
- This then takes effect by running the ``alembic`` script as::
- alembic -x dbname=postgresql://user:pass@host/dbname upgrade head
- This function does not require that the :class:`.MigrationContext`
- has been configured.
- .. seealso::
- :meth:`.EnvironmentContext.get_tag_argument`
- :attr:`.Config.cmd_opts`
- """
- def is_offline_mode() -> bool:
- """Return True if the current migrations environment
- is running in "offline mode".
- This is ``True`` or ``False`` depending
- on the ``--sql`` flag passed.
- This function does not require that the :class:`.MigrationContext`
- has been configured.
- """
- def is_transactional_ddl() -> bool:
- """Return True if the context is configured to expect a
- transactional DDL capable backend.
- This defaults to the type of database in use, and
- can be overridden by the ``transactional_ddl`` argument
- to :meth:`.configure`
- This function requires that a :class:`.MigrationContext`
- has first been made available via :meth:`.configure`.
- """
- def run_migrations(**kw: Any) -> None:
- """Run migrations as determined by the current command line
- configuration
- as well as versioning information present (or not) in the current
- database connection (if one is present).
- The function accepts optional ``**kw`` arguments. If these are
- passed, they are sent directly to the ``upgrade()`` and
- ``downgrade()``
- functions within each target revision file. By modifying the
- ``script.py.mako`` file so that the ``upgrade()`` and ``downgrade()``
- functions accept arguments, parameters can be passed here so that
- contextual information, usually information to identify a particular
- database in use, can be passed from a custom ``env.py`` script
- to the migration functions.
- This function requires that a :class:`.MigrationContext` has
- first been made available via :meth:`.configure`.
- """
- script: ScriptDirectory
- def static_output(text: str) -> None:
- """Emit text directly to the "offline" SQL stream.
- Typically this is for emitting comments that
- start with --. The statement is not treated
- as a SQL execution, no ; or batch separator
- is added, etc.
- """
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