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Diffstat (limited to 'rapid/scan.py')
| -rwxr-xr-x | rapid/scan.py | 170 |
1 files changed, 170 insertions, 0 deletions
diff --git a/rapid/scan.py b/rapid/scan.py new file mode 100755 index 0000000..ce882b4 --- /dev/null +++ b/rapid/scan.py @@ -0,0 +1,170 @@ +#!/usr/bin/python +# -*- coding: latin1 -*- + +### Copyright (C) 2011 Damon Lynch <damonlynch@gmail.com> + +### This program is free software; you can redistribute it and/or modify +### it under the terms of the GNU General Public License as published by +### the Free Software Foundation; either version 2 of the License, or +### (at your option) any later version. + +### This program is distributed in the hope that it will be useful, +### but WITHOUT ANY WARRANTY; without even the implied warranty of +### MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +### GNU General Public License for more details. + +### You should have received a copy of the GNU General Public License +### along with this program; if not, write to the Free Software +### Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + +import os +import multiprocessing + +import gio +import gtk + +import pyexiv2 + +import rpdmultiprocessing as rpdmp +import rpdfile + + +import logging +logger = multiprocessing.get_logger() + +# python whitespace is significant - don't remove the leading whitespace on +# the second line + +file_attributes = "standard::name,standard::display-name,\ +standard::type,standard::size,time::modified,access::can-read,id::file" + + + +class Scan(multiprocessing.Process): + + """Scans the given path for files of a specified type. + + Returns results in batches, finishing with a total of the size of all the + files in bytes. + """ + + def __init__(self, path, batch_size, generate_folder, results_pipe, + terminate_queue, run_event): + + """Setup values needed to conduct the scan. + + 'path' is a string of the path to be scanned, which is passed to gio. + + 'batch_size' is the number of files that should be sent back to the + calling function at one time. + + 'results_pipe' is a connection on which to send the results. + + 'terminate_queue' is a queue whose sole purpose is to notify the + process that it should terminate and not return any results. + + 'run_event' is an Event that is used to temporarily halt execution. + + """ + + multiprocessing.Process.__init__(self) + self.path = path + self.results_pipe = results_pipe + self.terminate_queue = terminate_queue + self.run_event = run_event + self.batch_size = batch_size + self.generate_folder = generate_folder + self.counter = 0 + self.files = [] + self.file_type_counter = rpdfile.FileTypeCounter() + + + def _gio_scan(self, path, file_size_sum): + """recursive function to scan a directory and its subdirectories + for photos and possibly videos""" + + children = path.enumerate_children(file_attributes) + + for child in children: + + # pause if instructed by the caller + self.run_event.wait() + + if not self.terminate_queue.empty(): + x = self.terminate_queue.get() + # terminate immediately + print "terminating..." + self.files = [] + return None + + # only collect files and scan in directories we can actually read + # cannot assume that users will download only from memory cards + + if child.get_attribute_boolean(gio.FILE_ATTRIBUTE_ACCESS_CAN_READ): + file_type = child.get_file_type() + name = child.get_name() + if file_type == gio.FILE_TYPE_DIRECTORY: + file_size_sum = self._gio_scan(path.get_child(name), + file_size_sum) + if file_size_sum is None: + return None + + elif file_type == gio.FILE_TYPE_REGULAR: + ext = os.path.splitext(name)[1].lower()[1:] + + file_type = rpdfile.file_type(ext) + if file_type is not None: + # count how many files of each type are included + # e.g. photo, video + self.file_type_counter.add(file_type) + self.counter += 1 + display_name = child.get_display_name() + size = child.get_size() + modification_time = child.get_modification_time() + file_id = child.get_attribute_string( + gio.FILE_ATTRIBUTE_ID_FILE) + scanned_file = rpdfile.get_rpdfile(ext, + name, + display_name, + path.get_path(), + size, + modification_time, + self.pid, + file_id) + + if self.generate_folder: + # this dramatically slows scanning speed, and it + # is unlikely this will be called this early in the + # workflow + scanned_file.read_metadata() + + self.files.append(scanned_file) + + if self.counter == self.batch_size: + # send batch of results + self.results_pipe.send((rpdmp.CONN_PARTIAL, + self.files)) + self.files = [] + self.counter = 0 + + file_size_sum += size + + return file_size_sum + + + def run(self): + """start the actual scan.""" + source = gio.File(self.path) + try: + size = self._gio_scan(source, 0) + except gio.Error, inst: + logger.error("Error while scanning %s: %s", self.path, inst) + size = None + + if size is not None: + if self.counter > 0: + # send any remaining results + self.results_pipe.send((rpdmp.CONN_PARTIAL, self.files)) + self.results_pipe.send((rpdmp.CONN_COMPLETE, (size, + self.file_type_counter, self.pid))) + self.results_pipe.close() |