plastid.util.services.decorators module¶

Function decorators useful for scripts or analyses

Decorators¶

catch_warnings(): Catch warnings raised by wrapped function
deprecated(): Function or class decorator. Wrapped functions or classes raise FutureWarnings when called or instantiated, respectively
parallelize(): Parallelize the running of a single-parameter function over multiple instances of its parameter
catch_stdout(): Redirect standard out from a wrapped function into a buffer
catch_stderr(): Redirect standard error from a wrapped function into a buffer
in_separate_process(): Run decorated function in a separate process, to force garbage collection of that function’s memory contents when the function completes and reduce overall long-term memory usage.
notimplemented(): Wrapped functions raise NotImplementedErrors. Use if committing incomplete code.
notused(): No effects. Used for code annotation only
skip_if_abstract(): Function decorator for unit tests. Wrapped methods will be skipped if they are called from a unittest.TestCase with ‘Abstract’ in its name, and run only in subclasses of the abstract unittest.TestCase in which they are defined

plastid.util.services.decorators.catch_stderr(buf=None)[source]¶

Function factory producing decorators that capture stderr to a buffer

Parameters

buffile: Buffer that will hold captured stderr output. Must import write() and fileno() methods. If None, os.devnull will be used.

Returns

function: Function decorator

Examples

Create a pipe, and use it to catch stderr:

>>> import sys
>>> import os
>>>
>>> def my_func():
>>>    sys.stderr.write("some message")

>>> read_end, write_end = os.pipe()
>>> buf = os.fdopen(write_end,"w")

>>> wrapped = catch_stderr(buf)(my_func)
>>> wrapped() # generates stderr

>>> buf.close()
>>> captured = os.fdopen(read_end).read()
>>> print(captured)
# output from captured stderr here

>>> captured.close() # remember to close!

plastid.util.services.decorators.catch_stdout(buf=None)[source]¶

Function factory producing decorators that capture stdout to a buffer

Parameters

buffile or None: Buffer that will hold captured stdout output. Must import write() and fileno() methods. If None, os.devnull will be used.

Returns

function: Function decorator

Examples

Create a pipe, and use it to catch stdout:

>>> import sys
>>> import os
>>>
>>> def my_func():
>>>     sys.stdout.write("some message")

>>> read_end, write_end = os.pipe()
>>> buf = os.fdopen(write_end,"w")
>>> 
>>> wrapped = catch_stdout(buf)(my_func)
>>> wrapped() # generates stdout

>>> buf.close()
>>> captured = os.fdopen(read_end).read()
>>> print(captured)
# output here

>>> captured.close() # remember to close!

plastid.util.services.decorators.catch_warnings(simple_filter='ignore')[source]¶

Function factory producing function decorators that suppress warnings

Parameters

simple_filterstr

Warnings filter action. Quoted from warnings:

Value

Disposition

error

Turn warnings into exceptions

ignore

Ignore all warnings

always

Always print warnings

default

Print first occurrence of each warning type, for each location where warning is issued

module

Print first occurrence of each warning type, for each module where warning is issued

once

Print first occurrence of matching warnings, regardless of location

(source: warnings)

This decorator does NOT support the onceperfamily custom warning action.

Returns

function: Decorator function