def waitForFile(self, filename: str, timeout: int = 0) -> Optional[str]:
"""
Wait for a specific filename to be created in the directory specified in initFileNotifier.
Args:
filename: Name of File to watch for creation of. If filename includes a path it must
match that specified in initFileNotifier.
timeout: Max number of seconds to watch for the file creation. If timeout expires
before the file is created then None will be returned
Returns:
The filename of the created file (same as input arg) or None if timeout expires
"""
_filedir, _filename = os.path.split(filename)
if _filedir in (None, ''):
filename = os.path.join(self.watchDir, filename)
elif _filedir != self.watchDir:
raise StateError(
f"FileWatcher: file path doesn't match watch directory: {_filedir}, {self.watchDir}"
)
fileExists = os.path.exists(filename)
if not fileExists:
if self.notify_thread is None:
raise FileNotFoundError(
"No fileNotifier and dicom file not found %s" % (filename))
else:
logStr = "FileWatcher: Waiting for file {}, timeout {}s ".format(
filename, timeout)
logging.log(DebugLevels.L6, logStr)
eventLoopCount = 0
exitWithFileEvent = False
eventTimeStamp = 0
startTime = time.time()
timeToCheckForFile = time.time(
) + 1 # check if file exists at least every second
while not fileExists:
if timeout > 0 and time.time() > (startTime + timeout):
return None
# look for file creation event
eventLoopCount += 1
try:
eventfile, ts = self.fileNotifyQ.get(block=True, timeout=1.0)
except Empty:
# The timeout occured on fileNotifyQ.get()
fileExists = os.path.exists(filename)
continue
if eventfile is None:
raise StateError('waitForFile: eventfile is None')
# We may have a stale event from a previous file if multiple events
# are created per file or if the previous file eventloop
# timed out and then the event arrived later.
if eventfile == filename:
fileExists = True
exitWithFileEvent = True
eventTimeStamp = ts
continue
if time.time() > timeToCheckForFile:
# periodically check if file exists, can occur if we get
# swamped with unrelated events
fileExists = os.path.exists(filename)
timeToCheckForFile = time.time() + 1
if exitWithFileEvent is False:
# We didn't get a file-close event because the file already existed.
# Check the file size and sleep up to 300 ms waitig for full size
waitIncrement = 0.1
totalWriteWait = 0.0
fileSize = os.path.getsize(filename)
while fileSize < self.minFileSize and totalWriteWait < 0.3:
time.sleep(waitIncrement)
totalWriteWait += waitIncrement
fileSize = os.path.getsize(filename)
logging.log(
DebugLevels.L6,
"File avail: eventLoopCount %d, fileEventCaptured %s, "
"fileName %s, eventTimeStamp %d", eventLoopCount,
exitWithFileEvent, filename, eventTimeStamp)
if self.demoStep is not None and self.demoStep > 0:
self.prevEventTime = demoDelay(self.demoStep, self.prevEventTime)
return filename
def waitForFile(self, specificFileName, timeout=0):
fileExists = os.path.exists(specificFileName)
if not fileExists:
if self.observer is None:
raise FileNotFoundError(
"No fileNotifier and dicom file not found %s" %
(specificFileName))
else:
logStr = "FileWatcher: Waiting for file {}, timeout {}s ".format(
specificFileName, timeout)
logging.log(DebugLevels.L6, logStr)
eventLoopCount = 0
exitWithFileEvent = False
eventTimeStamp = 0
startTime = time.time()
timeToCheckForFile = time.time(
) + 1 # check if file exists at least every second
while not fileExists:
if timeout > 0 and time.time() > (startTime + timeout):
return None
# look for file creation event
eventLoopCount += 1
try:
event, ts = self.fileNotifyQ.get(block=True, timeout=1.0)
except Empty as err:
# The timeout occured on fileNotifyQ.get()
fileExists = os.path.exists(specificFileName)
continue
if event is None:
raise StateError('waitForFile: event is None')
# We may have a stale event from a previous file if multiple events
# are created per file or if the previous file eventloop
# timed out and then the event arrived later.
if event.src_path == specificFileName:
fileExists = True
exitWithFileEvent = True
eventTimeStamp = ts
continue
if time.time() > timeToCheckForFile:
# periodically check if file exists, can occur if we get
# swamped with unrelated events
fileExists = os.path.exists(specificFileName)
timeToCheckForFile = time.time() + 1
# wait for the full file to be written, wait at most 300 ms
waitIncrement = 0.1
totalWriteWait = 0.0
fileSize = os.path.getsize(specificFileName)
while fileSize < self.minFileSize and totalWriteWait < 0.3:
time.sleep(waitIncrement)
totalWriteWait += waitIncrement
fileSize = os.path.getsize(specificFileName)
logging.log(
DebugLevels.L6,
"File avail: eventLoopCount %d, writeWaitTime %.3f, "
"fileEventCaptured %s, fileName %s, eventTimeStamp %.5f",
eventLoopCount, totalWriteWait, exitWithFileEvent,
specificFileName, eventTimeStamp)
if self.demoStep is not None and self.demoStep > 0:
self.prevEventTime = demoDelay(self.demoStep, self.prevEventTime)
return specificFileName