:mod:`compileall` --- Byte-compile Python libraries =================================================== .. module:: compileall :synopsis: Tools for byte-compiling all Python source files in a directory tree. **Source code:** :source:`Lib/compileall.py` -------------- This module provides some utility functions to support installing Python libraries. These functions compile Python source files in a directory tree. This module can be used to create the cached byte-code files at library installation time, which makes them available for use even by users who don't have write permission to the library directories. Command-line use ---------------- This module can work as a script (using :program:`python -m compileall`) to compile Python sources. .. program:: compileall .. cmdoption:: directory ... file ... Positional arguments are files to compile or directories that contain source files, traversed recursively. If no argument is given, behave as if the command line was ``-l ``. .. cmdoption:: -l Do not recurse into subdirectories, only compile source code files directly contained in the named or implied directories. .. cmdoption:: -f Force rebuild even if timestamps are up-to-date. .. cmdoption:: -q Do not print the list of files compiled. If passed once, error messages will still be printed. If passed twice (``-qq``), all output is suppressed. .. cmdoption:: -d destdir Directory prepended to the path to each file being compiled. This will appear in compilation time tracebacks, and is also compiled in to the byte-code file, where it will be used in tracebacks and other messages in cases where the source file does not exist at the time the byte-code file is executed. .. cmdoption:: -s strip_prefix .. cmdoption:: -p prepend_prefix Remove (``-s``) or append (``-p``) the given prefix of paths recorded in the ``.pyc`` files. Cannot be combined with ``-d``. .. cmdoption:: -x regex regex is used to search the full path to each file considered for compilation, and if the regex produces a match, the file is skipped. .. cmdoption:: -i list Read the file ``list`` and add each line that it contains to the list of files and directories to compile. If ``list`` is ``-``, read lines from ``stdin``. .. cmdoption:: -b Write the byte-code files to their legacy locations and names, which may overwrite byte-code files created by another version of Python. The default is to write files to their :pep:`3147` locations and names, which allows byte-code files from multiple versions of Python to coexist. .. cmdoption:: -r Control the maximum recursion level for subdirectories. If this is given, then ``-l`` option will not be taken into account. :program:`python -m compileall -r 0` is equivalent to :program:`python -m compileall -l`. .. cmdoption:: -j N Use *N* workers to compile the files within the given directory. If ``0`` is used, then the result of :func:`os.cpu_count()` will be used. .. cmdoption:: --invalidation-mode [timestamp|checked-hash|unchecked-hash] Control how the generated byte-code files are invalidated at runtime. The ``timestamp`` value, means that ``.pyc`` files with the source timestamp and size embedded will be generated. The ``checked-hash`` and ``unchecked-hash`` values cause hash-based pycs to be generated. Hash-based pycs embed a hash of the source file contents rather than a timestamp. See :ref:`pyc-invalidation` for more information on how Python validates bytecode cache files at runtime. The default is ``timestamp`` if the :envvar:`SOURCE_DATE_EPOCH` environment variable is not set, and ``checked-hash`` if the ``SOURCE_DATE_EPOCH`` environment variable is set. .. cmdoption:: -o level Compile with the given optimization level. May be used multiple times to compile for multiple levels at a time (for example, ``compileall -o 1 -o 2``). .. cmdoption:: -e dir Ignore symlinks pointing outside the given directory. .. cmdoption:: --hardlink-dupes If two ``.pyc`` files with different optimization level have the same content, use hard links to consolidate duplicate files. .. versionchanged:: 3.2 Added the ``-i``, ``-b`` and ``-h`` options. .. versionchanged:: 3.5 Added the ``-j``, ``-r``, and ``-qq`` options. ``-q`` option was changed to a multilevel value. ``-b`` will always produce a byte-code file ending in ``.pyc``, never ``.pyo``. .. versionchanged:: 3.7 Added the ``--invalidation-mode`` option. .. versionchanged:: 3.9 Added the ``-s``, ``-p``, ``-e`` and ``--hardlink-dupes`` options. Raised the default recursion limit from 10 to :py:func:`sys.getrecursionlimit()`. Added the possibility to specify the ``-o`` option multiple times. There is no command-line option to control the optimization level used by the :func:`compile` function, because the Python interpreter itself already provides the option: :program:`python -O -m compileall`. Similarly, the :func:`compile` function respects the :attr:`sys.pycache_prefix` setting. The generated bytecode cache will only be useful if :func:`compile` is run with the same :attr:`sys.pycache_prefix` (if any) that will be used at runtime. Public functions ---------------- .. function:: compile_dir(dir, maxlevels=sys.getrecursionlimit(), ddir=None, force=False, rx=None, quiet=0, legacy=False, optimize=-1, workers=1, invalidation_mode=None, *, stripdir=None, prependdir=None, limit_sl_dest=None, hardlink_dupes=False) Recursively descend the directory tree named by *dir*, compiling all :file:`.py` files along the way. Return a true value if all the files compiled successfully, and a false value otherwise. The *maxlevels* parameter is used to limit the depth of the recursion; it defaults to ``sys.getrecursionlimit()``. If *ddir* is given, it is prepended to the path to each file being compiled for use in compilation time tracebacks, and is also compiled in to the byte-code file, where it will be used in tracebacks and other messages in cases where the source file does not exist at the time the byte-code file is executed. If *force* is true, modules are re-compiled even if the timestamps are up to date. If *rx* is given, its search method is called on the complete path to each file considered for compilation, and if it returns a true value, the file is skipped. If *quiet* is ``False`` or ``0`` (the default), the filenames and other information are printed to standard out. Set to ``1``, only errors are printed. Set to ``2``, all output is suppressed. If *legacy* is true, byte-code files are written to their legacy locations and names, which may overwrite byte-code files created by another version of Python. The default is to write files to their :pep:`3147` locations and names, which allows byte-code files from multiple versions of Python to coexist. *optimize* specifies the optimization level for the compiler. It is passed to the built-in :func:`compile` function. Accepts also a sequence of optimization levels which lead to multiple compilations of one :file:`.py` file in one call. The argument *workers* specifies how many workers are used to compile files in parallel. The default is to not use multiple workers. If the platform can't use multiple workers and *workers* argument is given, then sequential compilation will be used as a fallback. If *workers* is 0, the number of cores in the system is used. If *workers* is lower than ``0``, a :exc:`ValueError` will be raised. *invalidation_mode* should be a member of the :class:`py_compile.PycInvalidationMode` enum and controls how the generated pycs are invalidated at runtime. The *stripdir*, *prependdir* and *limit_sl_dest* arguments correspond to the ``-s``, ``-p`` and ``-e`` options described above. They may be specified as ``str``, ``bytes`` or :py:class:`os.PathLike`. If *hardlink_dupes* is true and two ``.pyc`` files with different optimization level have the same content, use hard links to consolidate duplicate files. .. versionchanged:: 3.2 Added the *legacy* and *optimize* parameter. .. versionchanged:: 3.5 Added the *workers* parameter. .. versionchanged:: 3.5 *quiet* parameter was changed to a multilevel value. .. versionchanged:: 3.5 The *legacy* parameter only writes out ``.pyc`` files, not ``.pyo`` files no matter what the value of *optimize* is. .. versionchanged:: 3.6 Accepts a :term:`path-like object`. .. versionchanged:: 3.7 The *invalidation_mode* parameter was added. .. versionchanged:: 3.7.2 The *invalidation_mode* parameter's default value is updated to None. .. versionchanged:: 3.8 Setting *workers* to 0 now chooses the optimal number of cores. .. versionchanged:: 3.9 Added *stripdir*, *prependdir*, *limit_sl_dest* and *hardlink_dupes* arguments. Default value of *maxlevels* was changed from ``10`` to ``sys.getrecursionlimit()`` .. function:: compile_file(fullname, ddir=None, force=False, rx=None, quiet=0, legacy=False, optimize=-1, invalidation_mode=None, *, stripdir=None, prependdir=None, limit_sl_dest=None, hardlink_dupes=False) Compile the file with path *fullname*. Return a true value if the file compiled successfully, and a false value otherwise. If *ddir* is given, it is prepended to the path to the file being compiled for use in compilation time tracebacks, and is also compiled in to the byte-code file, where it will be used in tracebacks and other messages in cases where the source file does not exist at the time the byte-code file is executed. If *rx* is given, its search method is passed the full path name to the file being compiled, and if it returns a true value, the file is not compiled and ``True`` is returned. If *quiet* is ``False`` or ``0`` (the default), the filenames and other information are printed to standard out. Set to ``1``, only errors are printed. Set to ``2``, all output is suppressed. If *legacy* is true, byte-code files are written to their legacy locations and names, which may overwrite byte-code files created by another version of Python. The default is to write files to their :pep:`3147` locations and names, which allows byte-code files from multiple versions of Python to coexist. *optimize* specifies the optimization level for the compiler. It is passed to the built-in :func:`compile` function. Accepts also a sequence of optimization levels which lead to multiple compilations of one :file:`.py` file in one call. *invalidation_mode* should be a member of the :class:`py_compile.PycInvalidationMode` enum and controls how the generated pycs are invalidated at runtime. The *stripdir*, *prependdir* and *limit_sl_dest* arguments correspond to the ``-s``, ``-p`` and ``-e`` options described above. They may be specified as ``str``, ``bytes`` or :py:class:`os.PathLike`. If *hardlink_dupes* is true and two ``.pyc`` files with different optimization level have the same content, use hard links to consolidate duplicate files. .. versionadded:: 3.2 .. versionchanged:: 3.5 *quiet* parameter was changed to a multilevel value. .. versionchanged:: 3.5 The *legacy* parameter only writes out ``.pyc`` files, not ``.pyo`` files no matter what the value of *optimize* is. .. versionchanged:: 3.7 The *invalidation_mode* parameter was added. .. versionchanged:: 3.7.2 The *invalidation_mode* parameter's default value is updated to None. .. versionchanged:: 3.9 Added *stripdir*, *prependdir*, *limit_sl_dest* and *hardlink_dupes* arguments. .. function:: compile_path(skip_curdir=True, maxlevels=0, force=False, quiet=0, legacy=False, optimize=-1, invalidation_mode=None) Byte-compile all the :file:`.py` files found along ``sys.path``. Return a true value if all the files compiled successfully, and a false value otherwise. If *skip_curdir* is true (the default), the current directory is not included in the search. All other parameters are passed to the :func:`compile_dir` function. Note that unlike the other compile functions, ``maxlevels`` defaults to ``0``. .. versionchanged:: 3.2 Added the *legacy* and *optimize* parameter. .. versionchanged:: 3.5 *quiet* parameter was changed to a multilevel value. .. versionchanged:: 3.5 The *legacy* parameter only writes out ``.pyc`` files, not ``.pyo`` files no matter what the value of *optimize* is. .. versionchanged:: 3.7 The *invalidation_mode* parameter was added. .. versionchanged:: 3.7.2 The *invalidation_mode* parameter's default value is updated to None. To force a recompile of all the :file:`.py` files in the :file:`Lib/` subdirectory and all its subdirectories:: import compileall compileall.compile_dir('Lib/', force=True) # Perform same compilation, excluding files in .svn directories. import re compileall.compile_dir('Lib/', rx=re.compile(r'[/\\][.]svn'), force=True) # pathlib.Path objects can also be used. import pathlib compileall.compile_dir(pathlib.Path('Lib/'), force=True) .. seealso:: Module :mod:`py_compile` Byte-compile a single source file.