dosage/dosagelib/director.py
2014-03-04 18:38:46 +01:00

242 lines
7.8 KiB
Python

# -*- coding: iso-8859-1 -*-
# Copyright (C) 2014 Bastian Kleineidam
import threading
import thread
import os
try:
from Queue import Queue, Empty
except ImportError:
from queue import Queue, Empty
try:
from urllib.parse import urlparse
except ImportError:
from urlparse import urlparse
from .output import out
from . import events, scraper
from .util import getDirname
class ComicQueue(Queue):
"""The comic scraper job queue."""
def join(self, timeout=None):
"""Blocks until all items in the Queue have been gotten and processed.
The count of unfinished tasks goes up whenever an item is added to the
queue. The count goes down whenever a consumer thread calls task_done()
to indicate the item was retrieved and all work on it is complete.
When the count of unfinished tasks drops to zero, join() unblocks.
"""
self.all_tasks_done.acquire()
try:
while self.unfinished_tasks:
self.all_tasks_done.wait(timeout)
finally:
self.all_tasks_done.release()
def clear(self):
"""Remove all queue entries."""
self.mutex.acquire()
self.queue.clear()
self.mutex.release()
# ensure threads download only from one host at a time
host_locks = {}
def get_hostname(url):
"""Get hostname from URL."""
return list(urlparse(url))[1].lower()
lock = threading.Lock()
def get_host_lock(url):
"""Get lock object for given URL host."""
hostname = get_hostname(url)
return host_locks.setdefault(hostname, threading.Lock())
class ComicGetter(threading.Thread):
"""Get all strips of a comic in a thread."""
def __init__(self, options):
"""Store options."""
super(ComicGetter, self).__init__()
self.options = options
self.origname = self.getName()
self.stopped = False
self.errors = 0
def run(self):
"""Process from queue until it is empty."""
try:
while not self.stopped:
scraperobj = jobs.get(False)
self.setName(scraperobj.getName())
try:
self.getStrips(scraperobj)
finally:
jobs.task_done()
self.setName(self.origname)
except Empty:
pass
except KeyboardInterrupt:
thread.interrupt_main()
def getStrips(self, scraperobj):
"""Download comic strips."""
with lock:
host_lock = get_host_lock(scraperobj.url)
with host_lock:
self._getStrips(scraperobj)
def _getStrips(self, scraperobj):
"""Get all strips from a scraper."""
if self.options.all or self.options.cont:
numstrips = None
elif self.options.numstrips:
numstrips = self.options.numstrips
else:
# get current strip
numstrips = 1
try:
if scraperobj.isComplete(self.options.basepath):
out.info(u"All comics are already downloaded.")
return 0
for strip in scraperobj.getStrips(numstrips):
skipped = self.saveComicStrip(strip)
if skipped and self.options.cont:
# stop when retrieval skipped an image for one comic strip
out.info(u"Stop retrieval because image file already exists")
break
if self.stopped:
break
if self.options.all and not (self.errors or self.options.dry_run or
self.options.cont or scraperobj.indexes):
scraperobj.setComplete(self.options.basepath)
except Exception as msg:
out.exception(msg)
self.errors += 1
def saveComicStrip(self, strip):
"""Save a comic strip which can consist of multiple images."""
allskipped = True
for image in strip.getImages():
try:
if self.options.dry_run:
filename, saved = "", False
else:
filename, saved = image.save(self.options.basepath)
if saved:
allskipped = False
if self.stopped:
break
except Exception as msg:
out.exception('Could not save image at %s to %s: %r' % (image.referrer, image.filename, msg))
self.errors += 1
return allskipped
def stop(self):
self.stopped = True
jobs = ComicQueue()
threads = []
def getComics(options):
"""Retrieve comics."""
if options.handler:
for name in set(options.handler):
events.addHandler(name, options.basepath, options.baseurl)
events.getHandler().start()
errors = 0
try:
for scraperobj in getScrapers(options.comic, options.basepath, options.adult, options.multimatch):
jobs.put(scraperobj)
# start threads
num_threads = 1# XXX max(1, min(10, jobs.qsize()))
for i in range(num_threads):
t = ComicGetter(options)
threads.append(t)
t.start()
# wait for threads to finish
jobs.join(1)
for t in threads:
errors += t.errors
except ValueError as msg:
out.exception(msg)
errors += 1
except KeyboardInterrupt:
finish()
finally:
events.getHandler().end()
return errors
def finish():
out.warn("Interrupted!")
for t in threads:
t.stop()
jobs.clear()
out.warn("Waiting for download threads to finish.")
def getAllScrapers():
"""Get all scrapers."""
return getScrapers(['@@'])
def getScrapers(comics, basepath=None, adult=True, multiple_allowed=False):
"""Get scraper objects for the given comics."""
if '@' in comics:
# only scrapers whose directory already exists
if len(comics) > 1:
out.warn(u"using '@' as comic name ignores all other specified comics.")
for scraperclass in scraper.get_scraperclasses():
dirname = getDirname(scraperclass.getName())
if os.path.isdir(os.path.join(basepath, dirname)):
if not adult and scraperclass.adult:
warn_adult(scraperclass)
continue
yield scraperclass()
elif '@@' in comics:
# all scrapers
for scraperclass in scraper.get_scraperclasses():
if not adult and scraperclass.adult:
warn_adult(scraperclass)
continue
yield scraperclass()
else:
# get only selected comic scrapers
# store them in a set to eliminate duplicates
scrapers = set()
for comic in comics:
# Helpful when using shell completion to pick comics to get
comic.rstrip(os.path.sep)
if basepath and comic.startswith(basepath):
# make the following command work:
# find Comics -type d | xargs -n1 -P10 dosage -b Comics
comic = comic[len(basepath):].lstrip(os.sep)
if ':' in comic:
name, index = comic.split(':', 1)
indexes = index.split(',')
else:
name = comic
indexes = None
scraperclasses = scraper.find_scraperclasses(name, multiple_allowed=multiple_allowed)
for scraperclass in scraperclasses:
if not adult and scraperclass.adult:
warn_adult(scraperclass)
continue
scraperobj = scraperclass(indexes=indexes)
if scraperobj not in scrapers:
scrapers.add(scraperobj)
yield scraperobj
def warn_adult(scraperclass):
"""Print warning about adult content."""
out.warn(u"skipping adult comic %s; use the --adult option to confirm your age" % scraperclass.getName())