Source code for fsl.wrappers.wrapperutils

#!/usr/bin/env python
#
# wrapperutils.py - Functions and decorators used by the FSL wrapper
# functions.
#
# Author: Paul McCarthy <pauldmccarthy@gmail.com>
# Author: Martin Craig <martin.craig@eng.ox.ac.uk>
#
"""This module contains functions and decorators used by the FSL wrapper
functions.


The :func:`cmdwrapper` and :func:`fslwrapper` functions are convenience
decorators which allow you to write your wrapper function such that it simply
generates the command-line needed to respectively run a standard shell
command or a FSL command. For example::


    @fslwrapper
    def fslreorient2std(input, output):
        return ['fslreorient2std', input, output]


When this ``fslreorient2std`` function is called, the ``fslwrapper`` decorator
will take care of invoking the command in a standardised way.


The :func:`applyArgStyle` function can be used to automatically convert
keyword arguments into command-line arguments, based on a set of standard
patterns. For example::


    @fslwrapper
    def flirt(src, ref, **kwargs):
        cmd  = ['flirt', '-in', src, '-ref', ref]
        return cmd + applyArgStyle('-=', **kwargs)


The :func:`fileOrImage` and :func:`fileOrArray` functions can be used to
decorate a wrapper function such that in-memory ``nibabel`` images or Numpy
arrays can be passed in as arguments - they will be automatically saved out to
files, and then the file names passed into the wrapper function. For example::


    @fileOrImage('src', 'ref')
    @fslwrapper
    def flirt(src, ref, **kwargs):
        cmd  = ['flirt', '-in', src, '-ref', ref]
        return cmd + applyArgStyle('-=', **kwargs)


Now this ``flirt`` function can be called either with file names, or
``nibabel`` images.


.. note:: Because the :func:`fileOrImage` and :func:`fileOrArray` decorators
          manipulate the return value of the decorated function, they should
          be applied *after* any other decorators. Furthermore, if you need to
          apply both a ``fileOrImage`` and ``fileOrArray`` decorator to a
          function, they should be grouped together, e.g.::

              @fileOrImage('a', 'b')
              @fileOrArray('c', 'd')
              @fslwrapper
              def func(**kwargs):
                  ...


Command outputs can also be loaded back into memory by using the special
:data:`LOAD` value when calling a wrapper function. For example::


    @fileOrImage('src', 'ref', 'out')
    @fslwrapper
    def flirt(src, ref, **kwargs):
        cmd  = ['flirt', '-in', src, '-ref', ref]
        return cmd + applyArgStyle('-=', **kwargs)


If we set the ``out`` argument to ``LOAD``, the output image will be loaded
and returned::

    src     = nib.load('src.nii')
    ref     = nib.load('ref.nii')
    aligned = flirt(src, ref, out=LOAD)['out']
"""


import functools       as ft
import itertools       as it
import os.path         as op
import multiprocessing as mp
import collections.abc as abc
import                    os
import                    re
import                    sys
import                    glob
import                    random
import                    string
import                    pathlib
import                    fnmatch
import                    inspect
import                    logging
import                    tempfile
import                    threading
import                    warnings

import nibabel as nib
import numpy   as np

import fsl.utils.run        as run
import fsl.utils.assertions as asrt
import fsl.utils.path       as fslpath
import fsl.utils.tempdir    as tempdir
import fsl.data.image       as fslimage


log = logging.getLogger(__name__)


[docs] def _update_wrapper(wrapper, wrapped, *args, **kwargs): """Replacement for the built-in ``functools.update_wrapper``. This implementation ensures that the wrapper function has an attribute called ``__wrapped__``, which refers to the ``wrapped`` function. This custom function is only needed in Python versions < 3.4. """ wrapper = ft.update_wrapper(wrapper, wrapped, *args, **kwargs) # Python >= 3.4 does things right if (sys.version_info[0] * 10 + sys.version_info[1]) < 34: wrapper.__wrapped__ = wrapped return wrapper
[docs] def _unwrap(func): """Replacement for the built-in ``inspect.unwrap`` function, which is not present in Python versions prior to 3.4. """ # Python >= 3.4 has an inspect.unwrap function if (sys.version_info[0] * 10 + sys.version_info[1]) >= 34: return inspect.unwrap(func) # Otherwise we follow the __wrapped__ chain ourselves if hasattr(func, '__wrapped__'): return _unwrap(func.__wrapped__) return func
[docs] def _thread_id(): """Returns a unique identifier for the current process and thread. Used by :class:`FileOrThing` instances to differentiate independent threads of execution. """ t = threading.current_thread() p = mp.current_process() return f'{p.ident}_{t.ident}'
[docs] def genxwrapper(func, runner, funccmd=False): """This function is used by :func:`cmdwrapper` and :func:`fslwrapper`. It is not intended to be used in any other circumstances. This function generates a wrapper function which calls ``func`` to generate a command-line call, and then uses ``runner`` to invoke that command. ``func`` is assumed to be a wrapper function which generates a command- line. ``runner`` is assumed to be Either :func:`.run.run` or :func:`.run.runfsl`. The generated wrapper function will pass all of its arguments to ``func``, and will then pass the generated command-line to ``runner``, returning whatever is returned. The following keyword arguments will be intercepted by the wrapper function, and will *not* be passed to ``func``: - ``stdout``: Passed to ``runner``. Defaults to ``True``. - ``stderr``: Passed to ``runner``. Defaults to ``True``. - ``exitcode``: Passed to ``runner``. Defaults to ``False``. - ``submit``: Passed to ``runner``. Defaults to ``None``. - ``log``: Passed to ``runner``. Defaults to ``{'tee':True}``. - ``cmdonly``: Passed to ``runner``. Defaults to ``False``. The default values for these arguments are stored in the ``genxwrapper.run_options`` dictionary. This dictionary should not be changed directly, but rather can be temporarily modified via the :func:`wrapperconfig` context manager function. :arg func: A function which generates a command line. :arg runner: Either :func:`.run.run` or :func:`.run.runfsl`. :arg funccmd: Used by :func:`funcwrapper`. If ``True``, `func` is passed through :func:`.run.func_to_cmd`. """ def wrapper(*args, **kwargs): opts = genxwrapper.run_options stdout = kwargs.pop('stdout', opts['stdout']) stderr = kwargs.pop('stderr', opts['stderr']) exitcode = kwargs.pop('exitcode', opts['exitcode']) submit = kwargs.pop('submit', opts['submit']) cmdonly = kwargs.pop('cmdonly', opts['cmdonly']) silent = kwargs.pop('silent', False) # If silent=True, we need to explicitly set # log, as the run function will otherwise # ignore silent and preferentially use the # value we pass for log. if silent: logg = kwargs.pop('log', {'tee' : False}) else: logg = kwargs.pop('log', opts['log']) if funccmd: cmd = run.func_to_cmd(func, args=args, kwargs=kwargs, clean='always') # many wrapper functions use fsl.utils.assertions # statements to check that input arguments are # valid. Disable these if the cmdonly argument is # being used to generate a command without running # it, or if the call is to be submitted via fsl_sub # - it may be dependent on another job that has # not yet been run, so assertions on input files # may not be valid. else: with asrt.disabled(cmdonly or (submit not in (None, False))): cmd = func(*args, **kwargs) return runner(cmd, stderr=stderr, log=logg, submit=submit, cmdonly=cmdonly, stdout=stdout, exitcode=exitcode) return _update_wrapper(wrapper, func)
genxwrapper.run_options = { 'stdout' : True, 'stderr' : True, 'exitcode' : False, 'submit' : None, 'log' : {'tee' : True}, 'cmdonly' : False }
[docs] def cmdwrapper(func): """This decorator can be used on functions which generate a command line. It will pass the return value of the function to the :func:`fsl.utils.run.run` function in a standardised manner. See the :func:`genxwrapper` function for details. """ return genxwrapper(func, run.run)
[docs] def fslwrapper(func): """This decorator can be used on functions which generate a FSL command line. It will pass the return value of the function to the :func:`fsl.utils.run.runfsl` function in a standardised manner. See the :func:`genxwrapper` function for details. """ return genxwrapper(func, run.runfsl)
[docs] def funcwrapper(always=False): """This decorator can be used on Python functions which may need to be executed as shell commands via :func:`.run.func_to_cmd`. This decorator **must** be called when applied, i.e.:: @funcwrapper() def somefunc(): ... and not:: @funcwrapper def somefunc(): ... With the default behaviour (``always=False``), if the function is called *without* a ``submit`` parameter, the function will just be called as a normal Python function. If the function is called with ``submit=True`` (or similar), or if this decorator is applied with ``always=True``, the function will be executed in a separate process via :func:`.run.func_to_cmd`. See the :func:`genxwrapper` function for details. """ def decorator(func): def wrapped_func(*args, **kwargs): # submit as a shell command if always or kwargs.get('submit', None) not in (None, False): return genxwrapper(func, run.run, funccmd=True)(*args, **kwargs) # run directly as regular function else: return func(*args, **kwargs) return wrapped_func return decorator
[docs] class wrapperconfig: """Context manager to be used when calling wrapper functions. Can modify the options/arguments that are passed to :func:`fsl.utils.run.run` when calling a command from a wrapper function. For example:: with wrapperconfig(stdout=False): bet('struct', 'struct_brain') The ``wrapperconfig`` class has a class-level attribute called ``active`` which is set to ``True`` whenver any ``wrapperconfig`` call is in use. """ active = False
[docs] def __init__(self, **opts): self.newopts = dict(opts) self.oldopts = dict(genxwrapper.run_options) self.__active = None
[docs] def __enter__(self): genxwrapper.run_options.update(self.newopts) self.__active = wrapperconfig.active wrapperconfig.active = True
[docs] def __exit__(self, *_): genxwrapper.run_options = self.oldopts wrapperconfig.active = self.__active
SHOW_IF_TRUE = object() """Constant to be used in the ``valmap`` passed to the :func:`applyArgStyle` function. When a ``SHOW_IF_TRUE`` argument is ``True``, it is added to the generated command line arguments. """ HIDE_IF_TRUE = object() """Constant to be used in the ``valmap`` passed to the :func:`applyArgStyle` function. When a ``HIDE_IF_TRUE`` argument is ``True``, it is suppressed from the generated command line arguments. """ EXPAND_LIST = object() """Constant to be used in the ``valmap`` passed to the :func:`applyArgStyle` function. ``EXPAND_LIST`` argument values are expected to be sequences. Each element of the sequence will be added as a separate command line argument. For example:: applyArgStyle(argmap={'myarg' : EXPAND_LIST}, myarg=[1, 2, 3]) will be transformed into:: --myarg 1 --myarg 2 --myarg 3 """
[docs] def applyArgStyle(style=None, valsep=None, argmap=None, valmap=None, singlechar_args=False, charstyle=None, charsep=None, **kwargs): """Turns the given ``kwargs`` into command line options. This function is intended to be used to automatically generate command line options from arguments passed into a Python function. The default settings will generate arguments that match typical UNIX conventions, e.g. ``-a val``, ``--arg=val``, ``-a val1 val2``, ``--arg=val1,val2``. The ``style`` and ``valsep`` options (and ``charstyle`` and ``charsep``, for single-character/short arguments) control how key-value pairs are converted into command-line options: ========= ========== =========================== ``style`` ``valsep`` Result ========= ========== =========================== ``'-'`` ``' '`` ``-name val1 val2 val3`` ``'-'`` ``'"'`` ``-name "val1 val2 val3"`` ``'-'`` ``','`` ``-name val1,val2,val3`` ``'--'`` ``' '`` ``--name val1 val2 val3`` ``'--'`` ``'"'`` ``--name "val1 val2 val3"`` ``'--'`` ``','`` ``--name val1,val2,val3`` ``'-='`` ``' '`` Not supported ``'-='`` ``'"'`` ``-name="val1 val2 val3"`` ``'-='`` ``','`` ``-name=val1,val2,val3`` ``'--='`` ``' '`` Not supported ``'--='`` ``'"'`` ``--name="val1 val2 val3"`` ``'--='`` ``','`` ``--name=val1,val2,val3`` ========= ========== =========================== :arg style: Controls how the ``kwargs`` are converted into command-line options - must be one of ``'-'``, ``'--'``, ``'-='``, or ``'--='`` (the default). :arg valsep: Controls how the values passed to command-line options which expect multiple arguments are delimited - must be one of ``' '``, ``','`` or ``'"'``. Defaults to ``' '`` if ``'=' not in style``, ``','`` otherwise. :arg argmap: Dictionary of ``{kwarg-name : cli-name}`` mappings. This be used if you want to use different argument names in your Python function for the command-line options. ``argmap`` may also be a callable - in this case, every argument name will be passed to it, and its return value used as the command-line option. :arg valmap: Dictionary of ``{cli-name : value}`` mappings. This can be used to define specific semantics for some command-line options. Acceptable values for ``value`` are as follows - :data:`SHOW_IF_TRUE` - if the argument is present, and ``True`` in ``kwargs``, the command line option will be added (without any arguments). - :data:`HIDE_IF_TRUE` - if the argument is present, and ``False`` in ``kwargs``, the command line option will be added (without any arguments). - :data:`EXPAND_LIST` - The argument value is assumed to be a sequence - each element will be added as a separate command-line option. - Any other constant value. If the argument is present in ``kwargs``, its command-line option will be added, with the constant value as its argument. The argument for any options not specified in the ``valmap`` will be converted into strings. The argument names used in ``valmap`` must be the names used *after* any rules in ``argmap`` are applied. :arg charstyle: Separate style specification for single-character arguments. If ``style == '--='``, defaults to ``'-'``, matching UNIX conventions. Otherwise defaults to the value of ``style``. :arg charsep: Controls how the values passed to command-line options which expect multiple arguments are delimited - must be one of ``' '``, ``','`` or ``'"'``. Defaults to ``' '`` if ``'=' not in style``, ``','`` otherwise. :arg singlechar_args: If ``True``, equivalent to ``charstyle='-'``. This argument remains for compatibility, but may be removed in a future version. :arg kwargs: Arguments to be converted into command-line options. :returns: A sequence containing the generated command-line options, the same as what ``shlex.split`` would generate for a properly quoted string. """ if argmap is None: argmap = {} if valmap is None: valmap = {} if style is None: style = '--=' if charstyle is None: if singlechar_args: charstyle = '-' elif style == '--=': charstyle = '-' else: charstyle = style if valsep is None: if '=' in style: valsep = ',' else: valsep = ' ' if charsep is None: if '=' in charstyle: charsep = ',' else: charsep = ' ' if style not in ('-', '--', '-=', '--='): raise ValueError(f'Invalid style: {style}') if charstyle not in ('-', '--', '-=', '--='): raise ValueError(f'Invalid charstyle: {charstyle}') if valsep not in (' ', ',', '"'): raise ValueError(f'Invalid valsep: {valsep}') if charsep not in (' ', ',', '"'): raise ValueError(f'Invalid charsep: {charsep}') # It makes no sense to combine argument+value # with an equals sign, but not have the value # quoted (e.g "--arg=val1 val2 val3"). if '=' in style and valsep == ' ': raise ValueError(f'Incompatible style {style} ' 'and valsep ({valsep})') if '=' in charstyle and charsep == ' ': raise ValueError(f'Incompatible style {charstyle} ' 'and valsep ({charsep})') # apply argmap transform def maparg(arg): # argmap can either be a dictionary or a callable if callable(argmap): return argmap(arg) else: return argmap.get(arg, arg) # Format the argument. def fmtarg(arg, style): if style in ('--', '--='): return f'--{arg}' else: return f'-{arg}' # Formt the argument value. def fmtval(val, sep): if isinstance(val, abc.Sequence) and (not isinstance(val, str)): val = [str(v) for v in val] if sep == ' ': return val elif sep == '"': return [' '.join(val)] else: return [sep.join(val)] else: return [str(val)] # Combine the argument and value together. # val is assumed to be a sequence. def fmtargval(arg, val, style): # if '=' in style, val will # always be a single string if '=' in style: return ['{}={}'.format(arg, val[0])] else: return [arg] + val args = [] for k, v in kwargs.items(): if v is None: continue k = maparg(k) mapv = valmap.get(k, None) if len(k) == 1: sty, sep = charstyle, charsep else: sty, sep = style, valsep k = fmtarg(k, sty) if mapv in (SHOW_IF_TRUE, HIDE_IF_TRUE): if (mapv is SHOW_IF_TRUE and v) or \ (mapv is HIDE_IF_TRUE and not v): args.append(k) elif mapv == EXPAND_LIST: for vi in v: args.extend(fmtargval(k, fmtval(vi, sep), sty)) else: args.extend(fmtargval(k, fmtval(v, sep), sty)) return args
[docs] def namedPositionals(func, args): """Given a function, and a sequence of positional arguments destined for that function, identifies the name for each positional argument. Variable positional arguments are given an automatic name. :arg func: Function which will accept ``args`` as positionals. :arg args: Tuple of positional arguments to be passed to ``func``. """ # Remove any decorators # from the function func = _unwrap(func) # getargspec is the only way to # get the names of positional # arguments in Python 2.x. if sys.version_info[0] < 3: spec = inspect.getargspec(func) argnames = spec.args varargs = spec.varargs # But getargspec is deprecated # in python 3.x else: # getfullargspec is deprecated in # python 3.5, but not in python 3.6. with warnings.catch_warnings(): warnings.filterwarnings('ignore', category=DeprecationWarning) spec = inspect.getfullargspec(func) argnames = spec.args varargs = spec.varargs # we only care about the arguments # that are being passed in argnames = argnames[:len(args)] # generate names for varargs nvarargs = len(args) - len(argnames) suffix = namedPositionals.varargsSuffix if varargs is not None and nvarargs > 0: argnames += [f'{varargs}{i}{suffix}' for i in range(nvarargs)] return argnames
namedPositionals.varargsSuffix = '_VARARG' LOAD = object() """Constant used by the :class:`FileOrThing` class to indicate that an output file should be loaded into memory and returned as a Python object. """
[docs] class FileOrThing: """Decorator which ensures that certain arguments which are passed into the decorated function are always passed as file names. Both positional and keyword arguments can be specified. The ``FileOrThing`` class is not intended to be used directly - see the :func:`fileOrImage` and :func:`fileOrArray` decorator functions for more details. These decorators are intended for functions which wrap a command-line tool, i.e. where some inputs/outputs need to be specified as file names. **Inputs** Any arguments which are not of type ``Thing`` are passed through to the decorated function unmodified. Arguments which are of type ``Thing`` are saved to a temporary file, and the name of that file is passed to the function. **Outputs** If an argument is given the special :data:`LOAD` value, it is assumed to be an output argument. In this case, it is replaced with a temporary file name then, after the function has completed, that file is loaded into memory, and the value returned (along with the function's output, and any other arguments with a value of ``LOAD``). **Return value** Functions decorated with a ``FileOrThing`` decorator will always return a ``dict``-like object, where the function's actual return value is accessible via an attribute called ``stdout``. All output arguments with a value of ``LOAD`` will be present as dictionary entries, with the keyword argument names used as keys; these values will also be accessible as attributes of the results dict, when possible. Any ``LOAD`` output arguments which were not generated by the function will not be present in the dictionary. **Exceptions** The above description holds in all situations, except when arguments called ``submit`` and/or ``cmdonly`` are passed, and are set to values which evaluate to ``True``. In this case, the ``FileOrThing`` decorator will pass all arguments straight through to the decorated function, and will return its return value unchanged. This is because most functions that are decorated with the :func:`fileOrImage` or :func:`fileOrArray` decorators will invoke a call to :func:`.run.run` or :func:`.runfsl`, where: - a value of ``submit=True`` will cause the command to be executed asynchronously on a cluster platform. - a value of ``cmdonly=True`` will cause the command to *not* be executed, but instead the command that would have been executed is returned. A :exc:`ValueError` will be raised if the decorated function is called with ``submit=True`` and/or ``cmdonly=True``, and with any in-memory objects or ``LOAD`` symbols. **Example** As an example of using the ``fileOrArray`` decorator on a function which concatenates two files containing affine transformations, and saves the output to a file:: # if atob, btoc, or output are passed # in as arrays, they are converted to # file names. @fileOrArray('atob', 'btoc', 'output') def concat(atob, btoc, output=None): # inputs are guaranteed to be files atob = np.loadtxt(atob) btoc = np.loadtxt(atoc) atoc = np.dot(btoc, atob) if output is not None: np.savetxt(output, atoc) return 'Done' Because we have decorated the ``concat`` function with :func:`fileToArray`, it can be called with either file names, or Numpy arrays:: # All arguments are passed through # unmodified - the output will be # saved to a file called atoc.mat. concat('atob.txt', 'btoc.txt', 'atoc.mat') # The function's return value # is accessed via an attribute called # "stdout" on the dict assert concat('atob.txt', 'btoc.txt', 'atoc.mat').stdout == 'Done' # Outputs to be loaded into memory # are returned in a dictionary, # with argument names as keys. Values # can be accessed as dict items, or # as attributes. atoc = concat('atob.txt', 'btoc.txt', LOAD)['atoc'] atoc = concat('atob.txt', 'btoc.txt', LOAD).atoc # In-memory inputs are saved to # temporary files, and those file # names are passed to the concat # function. atoc = concat(np.diag([2, 2, 2, 0]), np.diag([3, 3, 3, 3]), LOAD).atoc **Using with other decorators** ``FileOrThing`` decorators can be chained with other ``FileOrThing`` decorators, and other decorators. When multiple ``FileOrThing`` decorators are used on a single function, the outputs from each decorator are merged together into a single dict-like object. ``FileOrThing`` decorators can be used with any other decorators **as long as** they do not manipulate the return value, and as long as the ``FileOrThing`` decorators are adjacent to each other. """
[docs] class Results(dict): """A custom ``dict`` type used to return outputs from a function decorated with ``FileOrThing``. All outputs are stored as dictionary items, with the argument name as key, and the output object (the "thing") as value. Where possible (i.e. for outputs named with a valid Python identifier), the outputs are also made accessible as attributes of the ``Results`` object. The decorated function's actual return value is accessible via the :meth:`stdout` property. """
[docs] def __init__(self, stdout): """Create a ``Results`` dict. :arg stdout: Return value of the decorated function (typically a tuple containing the standard output and error of the underlying command). """ super().__init__() self.__stdout = stdout
[docs] def __setitem__(self, key, val): """Add an item to the dict. The item is also added as an attribute. """ super().__setitem__(key, val) setattr(self, key, val)
@property def stdout(self): """Access the return value of the decorated function. """ return self.__stdout
[docs] def __init__(self, func, prepIn, prepOut, load, removeExt, *args, **kwargs): """Initialise a ``FileOrThing`` decorator. :arg func: The function to be decorated. :arg prepIn: Function which returns a file name to be used in place of an input argument. :arg prepOut: Function which generates a file name to use for arguments that were set to :data:`LOAD`. :arg load: Function which is called to load items for arguments that were set to :data:`LOAD`. Must accept the following arguments: - the name of the argument - path to the file to be loaded :arg removeExt: Function which can remove a file extension from a file path. :arg outprefix: Must be passed as a keyword argument. The name of a positional or keyword argument to the function, which specifies an output file name prefix. All other arguments with names that begin with this prefix may be interpreted as things to ``LOAD``. All other positional arguments are interpreted as the names of the arguments to the function which will be handled by this ``FileOrThing`` decorator. If not provided, *all* arguments passed to the function will be handled. The ``prepIn`` and ``prepOut`` functions must accept the following positional arguments: - A directory in which all temporary input/output files should be stored - The name of the keyword argument to be processed - The argument value that was passed in """ self.__func = func self.__prepIn = prepIn self.__prepOut = prepOut self.__load = load self.__removeExt = removeExt self.__things = args self.__outprefix = kwargs.get('outprefix', None)
[docs] def __call__(self, *args, **kwargs): """Function which calls ``func``, ensuring that any arguments of type ``Thing`` are saved to temporary files, and any arguments with the value :data:`LOAD` are loaded and returned. All other arguments are passed through to ``func``. """ func = self.__func argnames = namedPositionals(func, args) # Special case - if fsl.utils.run[fsl] is # being decorated (e.g. via cmdwrapper/ # fslwrapper), and submit=True or # cmdonly=True, this call will ultimately # submit the job to the cluster, or will # return the command that would have been # executed, and will return immediately. # # We error if we are given any in-memory # things, or LOAD symbols. # # n.b. testing values to be strings could # interfere with the fileOrText decorator. # Possible solution is to use pathlib? if kwargs.get('submit', False) or \ kwargs.get('cmdonly', False): allargs = {**dict(zip(argnames, args)), **kwargs} for name, val in allargs.items(): if (name in self.__things) and (not isinstance(val, str)): raise ValueError('Cannot use in-memory objects ' 'or LOAD with submit=True!') return func(*args, **kwargs) # If this FileOrThing is being called # by another FileOrThing don't create # another working directory. We do this # sneakily, by setting an attribute on # the wrapped function which stores the # current working directory. # # We use a unique identifier for this # thread of execution, in case multiple # wrapped functions are being invoked # simultaneously. wrapped = _unwrap(func) ident = _thread_id() fot_workdir = getattr(wrapped, f'_fot_workdir_{ident}', None) parent = fot_workdir is None # Create a tempdir to store any temporary # input/output things, but don't change # into it, as file paths passed to the # function may be relative. with tempdir.tempdir(changeto=False, override=fot_workdir) as td: log.debug('Redirecting LOADed outputs to %s', td) # Replace any things with file names. # Also get a list of LOAD outputs args = self.__prepareArgs(parent, td, argnames, args, kwargs) args, kwargs, outprefix, outfiles, prefixes = args # The prefix/patterns may be # overridden by a parent FoT outprefix = getattr(wrapped, f'_fot_outprefix_{ident}', outprefix) prefixes = getattr(wrapped, f'_fot_prefixes_{ident}', prefixes) # if there are any other FileOrThings # in the decorator chain, get them to # use our working directory, and # prefixes, instead of creating their # own. if parent: setattr(wrapped, f'_fot_workdir_{ident}', td) setattr(wrapped, f'_fot_outprefix_{ident}', outprefix) setattr(wrapped, f'_fot_prefixes_{ident}', prefixes) # Call the function try: result = func(*args, **kwargs) finally: # if we're the top-level FileOrThing # decorator, remove the attributes we # added above. if parent: delattr(wrapped, f'_fot_workdir_{ident}') delattr(wrapped, f'_fot_outprefix_{ident}') delattr(wrapped, f'_fot_prefixes_{ident}') return self.__generateResult( td, result, outprefix, outfiles, prefixes)
def __prepareArgs(self, parent, workdir, argnames, args, kwargs): """Prepares all input and output arguments to be passed to the decorated function. Any arguments with a value of :data:`LOAD` are passed to the ``prepOut`` function specified at :meth:`__init__`. All other arguments are passed through the ``prepIn`` function. :arg parent: ``True`` if this ``FileOrThing`` is the first in a chain of ``FileOrThing`` decorators. :arg workdir: Directory in which all temporary files should be stored. :arg argnames: Names for each positional argument. :arg args: Positional arguments to be passed to the decorated function. :arg kwargs: Keyword arguments to be passed to the decorated function. :returns: A tuple containing: - An updated copy of ``args``. - An updated copy of ``kwargs``. - The output file prefix that was actually passed in (it is subsequently modified so that prefixed outputs are redirected to a temporary location). All prefixed outputs that are not ``LOAD``ed should be moved into this directory. ``None`` if there is no output prefix. - A dictionary of ``{ name : filename }`` mappings, for all arguments with a value of ``LOAD``. - A dictionary of ``{ filepat : replstr }`` paths, for all output-prefix arguments with a value of ``LOAD``. """ # These containers keep track # of output files which are to # be loaded into memory outfiles = dict() prefixedFiles = dict() allargs = {k : v for k, v in zip(argnames, args)} allargs.update(kwargs) # Has an output prefix been specified? prefix = allargs.get(self.__outprefix, None) realPrefix = None # Prefixed outputs are only # managed by the parent # FileOrthing in a chain of # FoT decorators. if not parent: prefix = None # If so, replace it with a new output # prefix which will redirect all output # to the temp dir. # # Importantly, here we assume that the # underlying function (and hence the # underlying command-line tool) will # accept an output prefix which contains # a directory path. if prefix is not None: if isinstance(prefix, pathlib.Path): prefix = op.abspath(prefix) # If prefix is set to LOAD, # all generated output files # should be loaded - we use a # randomly generated prefix, # and add it to prefixedFiles, # so that every file which # starts with it will be # loaded. if prefix is LOAD: prefix = random.sample(string.ascii_letters, 10) prefix = ''.join(prefix) prefixedFiles[prefix] = self.__outprefix realPrefix = prefix fakePrefix = op.join(workdir, prefix) allargs[self.__outprefix] = fakePrefix log.debug('Replacing output prefix: %s -> %s', realPrefix, fakePrefix) # If the prefix specifies a # directory, make sure it # exists (remember that we're # in a temporary directory) pdir = op.dirname(fakePrefix) if pdir != '' and not op.exists(pdir): os.makedirs(pdir) if len(self.__things) > 0: things = self.__things else: things = allargs.keys() for name, val in list(allargs.items()): # don't process the # outprefix argument if name == self.__outprefix: continue # is this argument referring # to a prefixed output? isprefixed = (prefix is not None and name.startswith(prefix)) if not any((isprefixed, name in things, name.endswith(namedPositionals.varargsSuffix))): continue # Prefixed output files may only # be given a value of LOAD if isprefixed and val is not LOAD: raise ValueError('Cannot specify name of prefixed file - the ' 'name is defined by the output prefix: ' '{}'.format(name)) if val is LOAD: # this argument refers to an output # that is generated from the output # prefix argument, and doesn't map # directly to an argument of the # function. So we don't pass it # through. if isprefixed: prefixedFiles[name] = name allargs.pop(name) # regular output-file argument else: outfile = self.__prepOut(workdir, name, val) outfiles[name] = outfile allargs[ name] = outfile # Assumed to be an input file else: # sequences may be # accepted for inputs if isinstance(val, (list, tuple)): infile = list(val) for i, v in enumerate(val): v = self.__prepIn(workdir, name, v) if v is not None: infile[i] = v else: infile = self.__prepIn(workdir, name, val) if infile is not None: allargs[name] = infile if realPrefix is not None and len(prefixedFiles) == 0: allargs[self.__outprefix] = realPrefix # Turn any Path objects into absolute path # strings. Don't use Path.resolve(), as it # returns a relative path for non-existent # files/dirs on Windows/certain Python # versions. for k, v in allargs.items(): if isinstance(v, pathlib.Path): allargs[k] = op.abspath(v) args = [allargs.pop(k) for k in argnames] kwargs = allargs return args, kwargs, realPrefix, outfiles, prefixedFiles def __generateResult( self, workdir, result, outprefix, outfiles, prefixes): """Loads function outputs and returns a :class:`Results` object. Called by :meth:`__call__` after the decorated function has been called. Figures out what files should be loaded, and loads them into a ``Results`` object. :arg workdir: Directory which contains the function outputs. :arg result: Function return value. :arg outprefix: Original output prefix that was passed into the function (or ``None`` if one wasn't passed) :arg outfiles: Dictionary containing output files to be loaded (see :meth:`__prepareArgs`). :arg prefixes: Dictionary containing output-prefix patterns to be loaded (see :meth:`__prepareArgs`). :returns: A ``Results`` object containing all loaded outputs. """ # make a Results object to store # the output. If we are decorating # another FileOrThing, the # results will get merged together # into a single Results dict. if not isinstance(result, FileOrThing.Results): result = FileOrThing.Results(result) # Load the LOADed outputs for oname, ofile in outfiles.items(): log.debug('Loading output %s: %s', oname, ofile) if op.exists(ofile): oval = self.__load(oname, ofile) else: oval = None result[oname] = oval # No output prefix - we're done if outprefix is None or len(prefixes) == 0: return result # Load or move output-prefixed files. # Find all files with a name that # matches the prefix that was passed # in (recursing into matching sub- # directories too). allPrefixed = glob.glob(op.join(workdir, '{}*'.format(outprefix))) allPrefixed = [fslpath.allFiles(f) if op.isdir(f) else [f] for f in allPrefixed] for prefixed in it.chain(*allPrefixed): fullpath = prefixed prefixed = op.relpath(prefixed, workdir) for prefPat, prefName in prefixes.items(): if not fnmatch.fnmatch(prefixed, '{}*'.format(prefPat)): continue log.debug('Loading prefixed output %s [%s]: %s', prefPat, prefName, prefixed) noext = self.__removeExt(prefixed) prefPat = prefPat.replace('\\', '\\\\') noext = re.sub('^' + prefPat, prefName, noext) withext = re.sub('^' + prefPat, prefName, prefixed) # if the load function returns # None, this file is probably # not of the correct type. fval = self.__load(noext, fullpath) if fval is not None: # If there is already an item in result with the # name (stripped of prefix), then instead store # the result with the full prefixed name if noext not in result: result[noext] = fval else: result[withext] = fval break return result
[docs] def fileOrImage(*args, **kwargs): """Decorator which can be used to ensure that any NIfTI images are saved to file, and output images can be loaded and returned as ``nibabel`` image objects or :class:`.Image` objects. """ # keep track of the input argument # types on each call, so we know # whether to return a fsl.Image or # a nibabel image intypes = [] def prepIn(workdir, name, val): infile = None if isinstance(val, fslimage.Image): intypes.append(fslimage.Image) elif isinstance(val, nib.nifti1.Nifti1Image): intypes.append(nib.nifti1.Nifti1Image) if isinstance(val, fslimage.Image): val = val.nibImage if isinstance(val, nib.nifti1.Nifti1Image): infile = val.get_filename() # in-memory image - we have # to save it out to a file if infile is None or not op.exists(infile): hd, infile = tempfile.mkstemp(fslimage.defaultExt(), dir=workdir) os.close(hd) # Create a copy of the input image and # save that, so the original doesn't # get associated with the temp file val = nib.nifti1.Nifti1Image( np.asanyarray(val.dataobj), None, val.header) val.to_filename(infile) return infile def prepOut(workdir, name, val): return op.join(workdir, f'{name}{fslimage.defaultExt()}') def load(name, path): if not fslimage.looksLikeImage(path): return None # create an independent in-memory # copy of the image file img = nib.load(path, mmap=False) data = np.asanyarray(img.dataobj) # if any arguments were fsl images, # that takes precedence. if fslimage.Image in intypes: return fslimage.Image(data, header=img.header, name=name) # but if all inputs were file names, # nibabel takes precedence elif nib.nifti1.Nifti1Image in intypes or len(intypes) == 0: return nib.nifti1.Nifti1Image(data, None, img.header) # this function should not be called # under any other circumstances else: raise RuntimeError('Cannot handle type: {}'.format(intypes)) def decorator(func): fot = FileOrThing(func, prepIn, prepOut, load, fslimage.removeExt, *args, **kwargs) def wrapper(*args, **kwargs): result = fot(*args, **kwargs) intypes[:] = [] return result return _update_wrapper(wrapper, func) return decorator
[docs] def fileOrArray(*args, **kwargs): """Decorator which can be used to ensure that any Numpy arrays are saved to text files, and output files can be loaded and returned as Numpy arrays. """ def prepIn(workdir, name, val): infile = None if isinstance(val, np.ndarray): hd, infile = tempfile.mkstemp('.txt', dir=workdir) os.close(hd) np.savetxt(infile, val, fmt='%0.18f') return infile def prepOut(workdir, name, val): return op.join(workdir, '{}.txt'.format(name)) def load(_, path): try: return np.loadtxt(path) except Exception: return None def decorator(func): fot = FileOrThing(func, prepIn, prepOut, load, fslpath.removeExt, *args, **kwargs) def wrapper(*args, **kwargs): return fot(*args, **kwargs) return _update_wrapper(wrapper, func) return decorator
[docs] def fileOrText(*args, **kwargs): """Decorator which can be used to ensure that any text output (e.g. log file) are saved to text files, and output files can be loaded and returned as strings. To be able to distinguish between input values and input file paths, the ``fileOrText`` decorator requires that input and output file paths are passed in as ``pathlib.Path`` objects. For example, given a function like this:: @fileOrText() def myfunc(infile, outfile): ... if we want to pass file paths for both ``infile`` and ``outfile``, we would do this:: from pathlib import Path myfunc(Path('input.txt'), Path('output.txt')) Input values may be passed in as normal strings, e.g.:: myfunc('input data', Path('output.txt')) Output values can be loaded as normal via the :attr:`LOAD` symbol, e.g.:: myfunc(Path('input.txt'), LOAD) """ def prepIn(workdir, name, val): infile = None if not isinstance(val, pathlib.Path): with tempfile.NamedTemporaryFile(mode='w', suffix='.txt', dir=workdir, delete=False) as f: f.write(val) infile = f.name return infile def prepOut(workdir, name, val): return op.join(workdir, '{}.txt'.format(name)) def load(_, path): try: with open(path, "r") as f: return f.read() except Exception: return None def decorator(func): fot = FileOrThing(func, prepIn, prepOut, load, fslpath.removeExt, *args, **kwargs) def wrapper(*args, **kwargs): return fot(*args, **kwargs) return _update_wrapper(wrapper, func) return decorator