python.ext.silence Namespace Reference

Functions
def	make_fn (what, res, *args)
def	fifo ()
def	set_blocking (fd)
def	reader_thread_func (filename, filter_, real_stdout, filt_content)
def	threaded_file_reader (*args)
def	silence (filter_=lambda line:True, file_=stdout)
def	silence_sout_serr (filter_)
def	test ()
def	test_with_exception ()

Variables
	pyapi = PyDLL(None)
	this_exe = CDLL(None)
	FILE_p = c_void_p
def	PyFile_AsFile = make_fn(pyapi.PyFile_AsFile, FILE_p, py_object)
def	freopen = make_fn(this_exe.freopen, FILE_p, c_char_p, c_char_p, FILE_p)

Function Documentation

fifo()

def python.ext.silence.fifo

(

)

Create a fifo in a temporary place.

Definition at line 33 of file silence.py.

def fifo():
    """
    Create a fifo in a temporary place.
    """
    tmpdir = mkdtemp()
    filename = pjoin(tmpdir, 'myfifo')
    try:
        mkfifo(filename)
    except OSError as e:
        print("Failed to create FIFO: %s" % e, file=stderr)
        raise
    else:
        try:
            yield filename
        finally:
            remove(filename)
            rmdir(tmpdir)
 

make_fn()

def python.ext.silence.make_fn	(		what,
			res,
		*	args
	)

Definition at line 22 of file silence.py.

def make_fn(what, res, *args):
    what.restype = res
    what.argtypes = args
    return what
    

reader_thread_func()

def python.ext.silence.reader_thread_func	(		filename,
			filter_,
			real_stdout,
			filt_content
	)

Sit there, reading lines from the pipe `filename`, sending those for which
`filter_()` returns False to `real_stdout`

Definition at line 60 of file silence.py.

def reader_thread_func(filename, filter_, real_stdout, filt_content):
    """
    Sit there, reading lines from the pipe `filename`, sending those for which
    `filter_()` returns False to `real_stdout`
    """
    with fdopen(osopen(filename, O_NONBLOCK | O_RDONLY)) as fd:
        while True:
            rlist, _, _ = select([fd], [], [])
            
            line = fd.readline()
            if not line:
                break
                
            elif filter_(line):
                filt_content.write(line)
            else:
                real_stdout.write(line)
 
@contextmanager

set_blocking()

def python.ext.silence.set_blocking

(

fd

)

Set FD to be blocking

Definition at line 51 of file silence.py.

def set_blocking(fd):
    """
    Set FD to be blocking
    """
    flags = fcntl(fd, F_GETFL)
    if flags & O_NONBLOCK:
        flags ^= O_NONBLOCK
    fcntl(fd, F_SETFL, flags)
 

silence()

def python.ext.silence.silence	(		filter_ = lambda line: True,
			file_ = stdout
	)

Prevent lines matching `filter_` ending up on `file_` (defaults to stdout)

Definition at line 92 of file silence.py.

def silence(filter_=lambda line: True, file_=stdout):
    """
    Prevent lines matching `filter_` ending up on `file_` (defaults to stdout)
    """
    if not filter_:
        yield
        return
 
    import io
    file = io.IOBase
    if not isinstance(file_, file):
        # Unable to filter because it's not a file instance.
        yield
        return
    
    saved_stdout = dup(file_.fileno())
    stdout_file = PyFile_AsFile(file_)
    
    from io import StringIO
    filt_content = StringIO()
    
    with nested(fdopen(saved_stdout, "w"), fifo()) as (real_stdout, filename):
        try:
            tfr = threaded_file_reader(filename, filter_, 
                                       real_stdout, filt_content)
            with tfr:
                # Redirect stdout to pipe
                freopen(filename, "w", stdout_file)
                try:
                    yield filt_content
                finally:
                    # Redirect stdout back to it's original place
                    freopen("/dev/fd/%i" % saved_stdout, "w", stdout_file)
                    
        except Exception:
            print("Hit an exception. Filtered content:")
            print(filt_content.getvalue())
            raise
 
@contextmanager

silence_sout_serr()

def python.ext.silence.silence_sout_serr

(

filter_

)

Definition at line 132 of file silence.py.

def silence_sout_serr(filter_):
    from sys import stdout, stderr
    with nested(silence(filter_, stdout), silence(filter_, stderr)) as (so, se):
        yield so, se
            

test()

def python.ext.silence.test

(

)

Definition at line 137 of file silence.py.

def test():
    
    def filter_hello(line):
        if line.startswith("Data source lookup using"):
            return True
            
    print("Before with block..")
    
    with silence(filter_hello):
        from DQUtils.db import Databases
        f = Databases.get_folder("DQMFONL")
        print("Sensible stuff!")
    
    print("f =", f)
    
    print("I am after the silence block")
 

test_with_exception()

def python.ext.silence.test_with_exception

(

)

Definition at line 154 of file silence.py.

def test_with_exception():
    
    print("Before silence.")
    try:
        with silence() as filt_content:
            print("Hmm.")
            raise RuntimeError("Error.")
    except Exception:
        pass
    print("After silence")
    print("Stuff?", len(filt_content.getvalue()))
 

threaded_file_reader()

def python.ext.silence.threaded_file_reader

(

*

args

)

Operate a read_thread_func in another thread. Block with statement exit
until the function completes.

Definition at line 79 of file silence.py.

def threaded_file_reader(*args):
    """
    Operate a read_thread_func in another thread. Block with statement exit
    until the function completes.
    """
    reader_thread = Thread(target=reader_thread_func, args=args)
    reader_thread.start()
    try:
        yield
    finally:
        reader_thread.join()
 
@contextmanager

Variable Documentation

FILE_p

python.ext.silence.FILE_p = c_void_p

Definition at line 27 of file silence.py.

freopen

def python.ext.silence.freopen = make_fn(this_exe.freopen, FILE_p, c_char_p, c_char_p, FILE_p)

Definition at line 30 of file silence.py.

pyapi

python.ext.silence.pyapi = PyDLL(None)

Definition at line 19 of file silence.py.

PyFile_AsFile

def python.ext.silence.PyFile_AsFile = make_fn(pyapi.PyFile_AsFile, FILE_p, py_object)

Definition at line 29 of file silence.py.

this_exe

python.ext.silence.this_exe = CDLL(None)

Definition at line 20 of file silence.py.