posts/gallery/gallery.py

   1 #!/usr/bin/env python
   2 #
   3 # Copyright (C) 2010-2013 W. Trevor King <wking@tremily.us>
   4 #
   5 # This program is free software; you can redistribute it and/or modify
   6 # it under the terms of the GNU General Public License as published by
   7 # the Free Software Foundation; either version 2 of the License, or
   8 # (at your option) any later version.
   9 #
  10 # This program is distributed in the hope that it will be useful,
  11 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 # GNU General Public License for more details.
  14 #
  15 # You should have received a copy of the GNU General Public License
  16 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17
  18 """
  19 CGI gallery server for a picture directory organized along::
  20
  21   pics
  22   |-- some_directory
  23   |   |-- a_picture.jpg
  24   |   |-- another_picture.jpg
  25   |   |-- ...
  26   |-- another_directory
  27   |   |-- a_picture.jpg
  28   |   |-- captioned_picture.jpg
  29   |   |-- captioned_picture.jpg.txt
  30   |-- ...
  31
  32 With::
  33
  34   pics$ gallery.py
  35
  36 Note that you can store a caption for ``<PICTURE>`` as plain text in
  37 ``<PICTURE>.txt``.
  38
  39 See RFC 3875 for more details on the the Common Gateway Interface.
  40
  41 This script can also be run as a Simple Common Gateway Interface
  42 (SCGI) with the ``--scgi`` option.
  43 """
  44
  45 import logging as _logging
  46 import logging.handlers as _logging_handlers
  47 import math as _math
  48 import mimetypes as _mimetypes
  49 import os as _os
  50 import os.path as _os_path
  51 import random as _random
  52 import re as _re
  53 import subprocess as _subprocess
  54 try:  # Python 3
  55     import urllib.parse as _urllib_parse
  56 except ImportError:  # Python 2
  57     import urlparse as _urllib_parse
  58 import xml.sax.saxutils as _xml_sax_saxutils
  59
  60
  61 __version__ = '0.5'
  62
  63
  64 IMAGE_EXTENSIONS = ['.jpg', '.jpeg', '.tif', '.tiff', '.png', '.gif']
  65 VIDEO_EXTENSIONS = ['.mov', '.mp4', '.ogv']
  66 STREAMING_TYPES = ['video/ogg']
  67 RESPONSES = {  # httplib takes half a second to load
  68     200: 'OK',
  69     404: 'Not Found',
  70     }
  71
  72 LOG = _logging.getLogger('gallery.py')
  73 LOG.addHandler(_logging.StreamHandler())
  74 #LOG.addHandler(_logging_handlers.SysLogHandler())
  75 LOG.handlers[0].setFormatter(
  76     _logging.Formatter('%(asctime)s - %(name)s - %(levelname)s - %(message)s'))
  77 LOG.setLevel(_logging.DEBUG)
  78 #LOG.setLevel(_logging.WARNING)
  79
  80
  81 class CommandError(Exception):
  82     def __init__(self, command, status, stdout=None, stderr=None):
  83         strerror = ['Command failed (%d):\n  %s\n' % (status, stderr),
  84                     'while executing\n  %s' % str(command)]
  85         super(CommandError, self).__init__('\n'.join(strerror))
  86         self.command = command
  87         self.status = status
  88         self.stdout = stdout
  89         self.stderr = stderr
  90
  91
  92 class HTTPError(Exception):
  93     def __init__(self, status, message=None, content=None):
  94         if message is None:
  95             message = RESPONSES[status]
  96         super(HTTPError, self).__init__('{} {}'.format(status, message))
  97         self.status = status
  98         self.message = message
  99         self.content = content
 100
 101
 102 class ProcessingComplete(Exception):
 103     pass
 104
 105
 106 def invoke(args, stdin=None, stdout=_subprocess.PIPE, stderr=_subprocess.PIPE,
 107            expect=(0,), cwd=None, encoding=None):
 108     """
 109     expect should be a tuple of allowed exit codes.  cwd should be
 110     the directory from which the command will be executed.  When
 111     unicode_output == True, convert stdout and stdin strings to
 112     unicode before returing them.
 113     """
 114     if cwd == None:
 115         cwd = '.'
 116     LOG.debug('{}$ {}'.format(cwd, ' '.join(args)))
 117     try :
 118         q = _subprocess.Popen(args, stdin=_subprocess.PIPE, stdout=stdout,
 119                               stderr=stderr, cwd=cwd)
 120     except OSError as e:
 121         raise CommandError(args, status=e.args[0], stderr=e)
 122     stdout,stderr = q.communicate(input=stdin)
 123     status = q.wait()
 124     LOG.debug('{:d}\n{}{}'.format(status, stdout, stderr))
 125     if status not in expect:
 126         raise CommandError(args, status, stdout, stderr)
 127     return status, stdout, stderr
 128
 129 def is_image(filename):
 130     for extension in IMAGE_EXTENSIONS:
 131         if filename.lower().endswith(extension):
 132             return True
 133     return False
 134
 135 def is_video(filename):
 136     for extension in IMAGE_EXTENSIONS:
 137         if filename.lower().endswith(extension):
 138             return True
 139     return False
 140
 141 def image_base(filename):
 142     parts = filename.rsplit('.', 1)
 143     assert len(parts) == 2, parts
 144     return parts[0]
 145
 146
 147 class CGIGalleryServer (object):
 148     def __init__(self, base_path='.',
 149                  base_url='/',
 150                  cache_path='/tmp/gallery-cache/',
 151                  serve_originals=True):
 152         self._base_path = _os_path.abspath(base_path)
 153         self._base_url = base_url
 154         self._cache_path = cache_path
 155         self._serve_originals = serve_originals
 156         self._url_regexp = _re.compile('^[a-zA-Z0-9._/-]*$')
 157         self._rows = 3
 158         self._columns = 3
 159         self.header = []
 160         self.footer = []
 161
 162     def _http_header(self, mime='text/html', status=200):
 163         msg = RESPONSES[status]
 164         header = ['Status: {:d} {}'.format(status, msg)]
 165         if mime.startswith('text/'):
 166             charset = '; charset=UTF-8'
 167         else:
 168             charset = ''
 169         header.append('Content-type: {}{}'.format(mime, charset))
 170         return '\n'.join(header)
 171
 172     def _response(self, header=None, content='<h1>It works!</h1>',
 173                   stream=None):
 174         if header is None:
 175             header = self._http_header()
 176         stream.write(header)
 177         stream.write('\n\n')
 178         stream.write(content)
 179         raise ProcessingComplete()
 180
 181     def _response_stream(self, header=None, content=None, stream=None,
 182                          chunk_size=1024):
 183         LOG.debug('streaming response')
 184         if header is None:
 185             header = self._http_header()
 186         stream.write(header)
 187         stream.write('\n\n')
 188         stream.flush()  # flush headers
 189         while True:
 190             chunk = content.read(chunk_size)
 191             if not chunk:
 192                 break
 193             stream.write(chunk)
 194         raise ProcessingComplete()
 195
 196     def _error(self, status=404, content=None, stream=None):
 197         header = self._http_header(status=status)
 198         if content is None:
 199             content = RESPONSES[status]
 200         self._response(header=header, content=content, stream=stream)
 201
 202     def validate_url(self, url, exists=True, directory=False):
 203         LOG.debug('validating {} (exists={}, directory={})'.format(
 204                 repr(url), exists, directory))
 205         if url is None:
 206             return
 207         elif (not self._url_regexp.match(url) or
 208             url.startswith('/') or
 209             '..' in url
 210             ):
 211             LOG.error('invalid url')
 212             raise HTTPError(404)
 213         if exists:
 214             path = _os_path.join(self._base_path, url)
 215             if directory:
 216                 if not _os_path.isdir(path):
 217                     LOG.error('nonexistent directory')
 218                     raise HTTPError(404)
 219             else:
 220                 if not _os_path.isfile(path):
 221                     raise HTTPError(404, 'nonexistent file')
 222
 223     def serve(self, url=None, page=0, stream=None):
 224         LOG.info('serving url {} (page {})'.format(url, page))
 225         try:
 226             try:
 227                 if url is None:
 228                     self.index(stream=stream)
 229                 elif url.endswith('random'):
 230                     self.random(
 231                         url=url, stream=stream, max_width=500, max_height=500)
 232                 elif self.is_cacheable(url=url):
 233                     self.validate_url(url=url, exists=False)
 234                     self.cached(url=url, stream=stream)
 235                 else:
 236                     self.validate_url(url=url, exists=False, directory=True)
 237                     self.page(url=url, page=page, stream=stream)
 238                 raise HTTPError(404, 'unexpected URL type')
 239             except HTTPError as e:
 240                 LOG.error(e.message)
 241                 self._error(e.status, content=e.content, stream=stream)
 242         except ProcessingComplete:
 243             pass
 244
 245     def page_from_query(self, query=None, query_string=None):
 246         """Extract the requested page from a query string
 247
 248         This is a helper method for CGIGalleryServer consumers.
 249         Specify either query or query_string, but not both.
 250         """
 251         if query is None:
 252             query = _urllib_parse.parse_qs(query_string)
 253         page = 0
 254         if 'pp' in query:
 255             pp = query['pp']
 256             if isinstance(pp, list):
 257                 pp = pp[0]
 258             try:
 259                 page = int(pp) - 1
 260             except ValueError:
 261                 pass
 262         return page
 263
 264     def relative_url(self, url):
 265         if url is None:
 266             return url
 267         if not url.startswith(self._base_url):
 268             message = 'cannot convert {} to a relative URL of {}'.format(
 269                 url, self._base_url)
 270             raise HTTPError(404, message)
 271         if url == self._base_url:
 272             return None
 273         return url[len(self._base_url):]
 274
 275     def _url(self, path):
 276         relpath = _os_path.relpath(
 277             _os_path.join(self._base_path, path), self._base_path)
 278         if relpath == '.':
 279             relpath = ''
 280         elif path.endswith('/'):
 281             relpath += '/'
 282         return '{}{}'.format(self._base_url, relpath)
 283
 284     def _label(self, path):
 285         dirname,base = _os_path.split(path)
 286         if not base:  # directory path ending with '/'
 287             dirname,base = _os_path.split(dirname)
 288         return base.replace('_', ' ').title()
 289
 290     def _link(self, path, text=None):
 291         if text is None:
 292             text = self._label(path)
 293         return '<a href="{}">{}</a>'.format(self._url(path), text)
 294
 295     def _subdirs(self, path):
 296         try:
 297             order = [d.strip() for d in
 298                      open(_os_path.join(path, '_order')).readlines()]
 299         except IOError:
 300             order = []
 301         dirs = sorted(_os.listdir(path))
 302         start = []
 303         for d in order:
 304             if d in dirs:
 305                 start.append(d)
 306                 dirs.remove(d)
 307         for d in start + dirs:
 308             dirpath = _os_path.join(path, d)
 309             if _os_path.isdir(dirpath):
 310                 yield dirpath
 311
 312     def _images(self, path):
 313         for p in sorted(_os.listdir(path)):
 314             if p.startswith('.') or p.endswith('~'):
 315                 continue
 316             picture_path = _os_path.join(path, p)
 317             if is_image(picture_path):
 318                 yield picture_path
 319
 320     def index(self, stream=None):
 321         LOG.debug('index page')
 322         return self._directory(self._base_path, stream=stream)
 323
 324     def _original_url(self, url):
 325         """Reverse thumbnail URL mapping
 326
 327         Returns (original_url, generating_callback, callback_kwargs).
 328         """
 329         base,extension = _os_path.splitext(url)
 330         if extension in ['.png']:
 331             try:
 332                 root,width,height = base.rsplit('-', 2)
 333             except ValueError:
 334                 raise HTTPError(404, 'missing width/height in {}'.format(base))
 335             try:
 336                 width = int(width)
 337                 height = int(height)
 338             except ValueError as e:
 339                 raise HTTPError(404, 'invalid width/height: {}'.format(e))
 340             return (
 341                 root + '.jpg',
 342                 self._thumb,
 343                 {'max_width': width,
 344                  'max_height': height},
 345                 )
 346         elif extension in VIDEO_EXTENSIONS:
 347             return (
 348                 base + '.mov',
 349                 getattr(self, '_{}'.format(extension), None),
 350                 {},
 351                 )
 352         raise HTTPError(404, 'no original URL for {}'.format(url))
 353
 354     def _thumb(self, image, max_width=None, max_height=None):
 355         if not _os_path.exists(self._cache_path):
 356             _os.makedirs(self._cache_path)
 357         dirname,filename = _os_path.split(image)
 358         reldir = _os_path.relpath(dirname, self._base_path)
 359         cache_dir = _os_path.join(self._cache_path, reldir)
 360         if not _os_path.isdir(cache_dir):
 361             _os.makedirs(cache_dir)
 362         extension = '-{:d}-{:d}.png'.format(max_width, max_height)
 363         thumb_filename = image_base(filename)+extension
 364         thumb_url = _os_path.join(dirname, thumb_filename)
 365         thumb_path = _os_path.join(cache_dir, thumb_filename)
 366         image_path = _os_path.join(self._base_path, image)
 367         if not _os_path.isfile(image_path):
 368             raise HTTPError(404, 'image path for thumbnail does not exist')
 369         if (not _os_path.isfile(thumb_path)
 370             or _os_path.getmtime(image_path) > _os_path.getmtime(thumb_path)):
 371             invoke(['convert', '-format', 'png', '-strip', '-quality', '95',
 372                     image_path,
 373                     '-thumbnail', '{:d}x{:d}'.format(max_width, max_height),
 374                     thumb_path])
 375         return (thumb_path, self._url(thumb_url))
 376
 377     def _mp4(self, video, *args):
 378         if not video.endswith('.mov'):
 379             raise HTTPError(404, "can't translate {} to MPEGv4".format(video))
 380         dirname,filename = _os_path.split(video)
 381         mp4_filename = image_base(filename) + '.mp4'
 382         reldir = _os_path.relpath(dirname, self._base_path)
 383         cache_dir = _os_path.join(self._cache_path, reldir)
 384         if not _os_path.isdir(cache_dir):
 385             _os.makedirs(cache_dir)
 386         mp4_url = _os_path.join(dirname, mp4_filename)
 387         mp4_path = _os_path.join(cache_dir, mp4_filename)
 388         if not _os_path.isfile(video):
 389             raise HTTPError(404, 'source video path does not exist')
 390         if (not _os_path.isfile(mp4_path)
 391             or _os_path.getmtime(video) > _os_path.getmtime(mp4_path)):
 392             arg = ['ffmpeg', '-i', video, '-acodec', 'libfaac', '-aq', '200',
 393                    '-ac', '1', '-s', '640x480', '-vcodec', 'libx264',
 394                    '-preset', 'slower', '-vpre', 'ipod640', '-b', '800k',
 395                    '-bt', '800k', '-aspect', '640:480', '-threads', '0']
 396             arg.extend(args)
 397             arg.append(mp4_path)
 398             invoke(arg)
 399         return (mp4_path, self._url(mp4_url))
 400
 401     def _ogv(self, video, *args):
 402         if not video.endswith('.mov'):
 403             LOG.error("can't translate {} to Ogg Video".format(video))
 404         dirname,filename = _os_path.split(video)
 405         ogv_filename = image_base(filename) + '.ogv'
 406         reldir = _os_path.relpath(dirname, self._base_path)
 407         cache_dir = _os_path.join(self._cache_path, reldir)
 408         if not _os_path.isdir(cache_dir):
 409             _os.makedirs(cache_dir)
 410         ogv_url = _os_path.join(dirname, ogv_filename)
 411         ogv_path = _os_path.join(cache_dir, ogv_filename)
 412         if not _os_path.isfile(video):
 413             LOG.error('source video path does not exist')
 414         if (not _os_path.isfile(ogv_path)
 415             or _os_path.getmtime(video) > _os_path.getmtime(ogv_path)):
 416             arg = ['ffmpeg2theora', '--optimize']
 417             arg.extend(args)
 418             arg.extend(['--output', ogv_path, video])
 419             invoke(arg)
 420         return (ogv_path, self._url(ogv_url))
 421
 422     def _get_image_caption(self, path):
 423         caption_path = path + '.txt'
 424         try:
 425             return open(caption_path, 'r').read()
 426         except IOError:
 427             return None
 428
 429     def _get_image_video(self, path, fallback=None):
 430         base_path = image_base(path)
 431         for extension in VIDEO_EXTENSIONS:
 432             video_path = base_path + extension
 433             if _os_path.isfile(video_path):
 434                 return self._video(video_path, fallback=fallback)
 435         return None
 436
 437     def _captioned_video(self, path, href=None):
 438         img = self._image(path, max_width=640, max_height=480)
 439         caption = self._get_image_caption(path)
 440         video = self._get_image_video(path, fallback=[img])
 441         content = []
 442         if video:
 443             content.extend(video)
 444             if href:
 445                 content.append('<p>{}</p>'.format(
 446                         self._link(path=href, text='gallery page')))
 447         elif href:
 448             content.append(self._link(path=href, text=img))
 449         else:
 450             content.append(img)
 451         if caption:
 452             caption = _xml_sax_saxutils.escape(caption)
 453             content.append('<p>{}</p>'.format(caption))
 454         return content
 455
 456     def _video(self, video, fallback=None, **kwargs):
 457         if fallback is None:
 458             fallback = [
 459                 '<p>Your browser does not support the &lt;video&gt; tag, try',
 460                 'downloading the video and playing it in an external player.',
 461                 '</p>',
 462                 ]
 463         fallback = ['    '+line for line in fallback]
 464         ogv_path,ogv_url = self._ogv(video)
 465         mp4_path,mp4_url = self._mp4(video)
 466         return [
 467             '<p>',
 468             ('  <video preloads="none" controls="controls" '
 469              'width="640" height="480">'),
 470             '    <source src="{}"'.format(mp4_url),
 471             ('''            type='video/mp4; '''
 472              '''codecs="avc1.42E01E, mp4a.40.2"' />'''),
 473             '    <source src="{}"'.format(ogv_url),
 474             '''            type='video/ogg; codecs="theora,vorbis"' />''',
 475             ] + fallback + [
 476             '  </video>',
 477             '</p>',
 478             '<p>Download as',
 479             '  <a href="{}">Ogg/Theora/Vorbis</a> or'.format(ogv_url),
 480             ('  <a href="{}">Mpeg4/H.264(ConstrainedBaselineProfile)/AAC</a>.'
 481              ).format(mp4_url),
 482             '<p>',
 483             ]
 484
 485     def _image(self, image, **kwargs):
 486         if kwargs:
 487             image_path,image_url = self._thumb(image, **kwargs)
 488         else:
 489             image_url = image
 490         sections = ['<img src="{}"'.format(image_url)]
 491         caption = self._get_image_caption(path=image)
 492         if caption:
 493             caption = _xml_sax_saxutils.quoteattr(
 494                 caption.replace('\n', ' ').strip())
 495             sections.extend([
 496                     'title={}'.format(caption),
 497                     'alt={}'.format(caption),
 498                     ])
 499         sections.append('/>')
 500         return ' '.join(sections)
 501
 502     def _image_page(self, image):
 503         return image_base(image) + '/'
 504
 505     def random(self, url=None, stream=None, **kwargs):
 506         LOG.debug('random image')
 507         if url.endswith('/random'):
 508             url = url[:(-len('/random'))]
 509             self.validate_url(url=url, directory=True, stream=stream)
 510             base_dir = _os_path.join(self._base_path, url)
 511         elif url == 'random':
 512             base_dir = self._base_path
 513         else:
 514             raise HTTPError(404)
 515         images = []
 516         for dirpath,dirnames,filenames in _os.walk(base_dir):
 517             for filename in filenames:
 518                 if is_image(filename):
 519                     images.append(_os_path.join(dirpath, filename))
 520         if not images:
 521             self._response(content='<p>no images to choose from</p>',
 522                            stream=stream)
 523         image = _random.choice(images)
 524         LOG.debug('selected random image {}'.format(image))
 525         page = self._image_page(image)
 526         content = self._captioned_video(path=image, href=page)
 527         self._response(content='\n'.join(content), stream=stream)
 528
 529     def is_cacheable(self, url):
 530         return is_image(url) or is_video(url)
 531
 532     def cached(self, url, stream=None):
 533         LOG.debug('retrieving possibly cached item')
 534         mime = _mimetypes.guess_type(url)[0]
 535         if mime is None:
 536             raise HTTPError(404, 'unknown mime type for {}'.format(url))
 537         cache_path = _os_path.join(self._cache_path, url)
 538         original_path = _os_path.join(self._base_path, url)
 539         path = None
 540         if _os_path.isfile(cache_path):
 541             LOG.debug('return cached item {}'.format(cache_path))
 542             path = cache_path
 543         elif self._serve_originals and _os_path.isfile(original_path):
 544             LOG.debug('return original item {}'.format(original_path))
 545             path = original_path
 546         else:
 547             LOG.debug('possibly create cached item {}'.format(cache_path))
 548             original_url,callback,kwargs = self._original_url(url)
 549             original_path = _os_path.join(self._base_path, original_url)
 550             if callback and _os_path.isfile(original_path):
 551                 path,cache_url = callback(original_path, **kwargs)
 552         if not path:
 553             raise HTTPError(404)
 554         try:
 555             content = open(path, 'rb')
 556         except IOError as e:
 557             LOG.error(e)
 558             raise HTTPError(404, 'item not found {}'.format(url))
 559         header = self._http_header(mime=mime)
 560         if mime in STREAMING_TYPES:
 561             self._response_stream(
 562                 header=header, content=content, stream=stream)
 563         content = content.read()
 564         self._response(header=header, content=content, stream=stream)
 565
 566     def page(self, url, page=0, stream=None):
 567         LOG.debug('HTML page {} {}'.format(url, page))
 568         if not url.endswith('/'):
 569             raise HTTPError(404, 'HTML page URLs must end with a slash')
 570         abspath = _os_path.join(self._base_path, url)
 571         if _os_path.isdir(abspath):
 572             self._directory(path=abspath, page=page, stream=stream)
 573         for extension in IMAGE_EXTENSIONS:
 574             file_path = abspath[:-1] + extension
 575             if _os_path.isfile(file_path):
 576                 self._page(path=file_path, stream=stream)
 577         raise HTTPError(404, 'unknown HTML page {}'.format(url))
 578
 579     def _directory_header(self, path):
 580         relpath = _os_path.relpath(path, self._base_path)
 581         crumbs = []
 582         dirname = relpath
 583         while dirname:
 584             dirname,base = _os_path.split(dirname)
 585             if base != '.':
 586                 crumbs.insert(0, base)
 587         crumbs.insert(0, '')
 588         links = [None] * len(crumbs)
 589         for i,c in enumerate(crumbs):
 590             if i < len(crumbs)-1:
 591                 if i == 0:
 592                     links[i] = self._link(self._base_path, 'Gallery')
 593                 else:
 594                     relpath = '/'.join(crumbs[1:i+1]) + '/'
 595                     fullpath = _os_path.join(self._base_path, relpath)
 596                     links[i] = self._link(path=fullpath)
 597             else:
 598                 if i == 0:
 599                     links[i] = 'Gallery'
 600                 else:
 601                     links[i] = self._label(crumbs[i])
 602         content = ['<h1>{}</h1>'.format(' '.join(links))]
 603         return content
 604
 605     def _directory_page_navigation(self, path, page, pages):
 606         if pages <= 1:
 607             return []
 608         prev_page = path + '?pp={:d}'.format((page - 1) % pages + 1)
 609         next_page = path + '?pp={:d}'.format((page + 1) % pages + 1)
 610         return [
 611             '<div style="text-align: center;">',
 612             '<p>',
 613             self._link(prev_page, 'previous'),
 614             '({:d} of {:d})'.format(page+1, pages),
 615             self._link(next_page, 'next'),
 616             '</p>',
 617             '</div>',
 618            ]
 619
 620     def _directory_subdirs(self, path):
 621         content = []
 622         dirs = list(self._subdirs(path))
 623         if dirs:
 624             content.append('<ul>')
 625             for d in dirs:
 626                 content.append('  <li>{}</li>'.format(self._link(d+'/')))
 627             content.append('</ul>')
 628         return content
 629
 630     def _directory_images(self, path, images):
 631         content = ['<table style="margin-left: auto; margin-right: auto;">']
 632         column = 0
 633         for image in images:
 634             page = self._image_page(image)
 635             img = self._image(image, max_width=300, max_height=300)
 636             link = self._link(page, img)
 637             if column == 0:
 638                 content.append('  <tr>')
 639             content.extend([
 640                     '    <td style="text-align: center;">',
 641                     '      {}'.format(link),
 642                     '    </td>',
 643                     ])
 644             column += 1
 645             if column == self._columns:
 646                 content.append('  </tr>')
 647                 column = 0
 648         if column != 0:
 649             #content.extend()
 650             content.append('  </tr>')
 651         content.append('</table>')
 652         return content
 653
 654     def _directory(self, path, page=0, stream=None):
 655         LOG.debug('directory page {} {}'.format(path, page))
 656         images = list(self._images(path))
 657         images_per_page = self._rows * self._columns
 658         pages = int(_math.ceil(float(len(images)) / images_per_page)) or 1
 659         if page < 0 or page >= pages:
 660             raise HTTPError(
 661                 404,
 662                 'page out of bounds for this gallery 0 <= {:d} < {:d}'.format(
 663                     page, pages))
 664         first_image = images_per_page * page
 665         images = images[first_image:first_image+images_per_page]
 666         content = []
 667         content.extend(self.header)
 668         content.extend(self._directory_header(path))
 669         nav = self._directory_page_navigation(path, page=page, pages=pages)
 670         content.extend(nav)
 671         content.extend(self._directory_subdirs(path))
 672         content.extend(self._directory_images(path, images=images))
 673         content.extend(nav)
 674         content.extend(self.footer)
 675         self._response(content='\n'.join(content), stream=stream)
 676
 677     def _page(self, path, stream=None):
 678         LOG.debug('image page {}'.format(path))
 679         gallery = _os_path.dirname(path)
 680         images = list(self._images(gallery))
 681         images_per_page = self._rows * self._columns
 682         i = images.index(path)
 683         page = i / images_per_page
 684         gallery_page = '{}/?pp={:d}'.format(gallery, page + 1)
 685         prev_page = self._image_page(images[i - 1])
 686         next_page = self._image_page(images[(i + 1) % len(images)])
 687         content = []
 688         content.extend(self.header)
 689         content.extend([
 690                 '<div style="text-align: center;">',
 691                 '<p>',
 692                 self._link(prev_page, 'previous'),
 693                 self._link(gallery_page, 'all'),
 694                 self._link(next_page, 'next'),
 695                 '</p>',
 696                 ])
 697         content.extend(self._captioned_video(path))
 698         content.append('</div>')
 699         content.extend(self.footer)
 700         self._response(content='\n'.join(content), stream=stream)
 701
 702
 703 def serve_cgi(server):
 704     import cgi
 705     import cgitb
 706     import sys
 707
 708     url=None
 709     cgitb.enable()
 710     #cgitb.enable(display=0, logdir="/tmp/")
 711     data = cgi.FieldStorage()
 712     page = server.page_from_query(
 713         query={key: data[key].getlist() for key in data.keys()})
 714     if 'p' in data:
 715         p = data['p']
 716         if isinstance(p, list):
 717             p = p[0]
 718         url = p.value
 719     server.serve(url=url, page=page, stream=sys.stdout)
 720
 721 def serve_scgi(server, host='localhost', port=4000):
 722     import scgi
 723     import scgi.scgi_server
 724
 725     class GalleryHandler(scgi.scgi_server.SCGIHandler):
 726         def produce(self, env, bodysize, input, output):
 727             #LOG.info(HTTP_USER_AGENT REQUEST_METHOD REMOTE_ADDR REQUEST_URI
 728             url = env.get('DOCUMENT_URI', None)
 729             page = server.page_from_query(
 730                 query_string=env.get('QUERY_STRING', ''))
 731             try:
 732                 try:
 733                     url = server.relative_url(url=url)
 734                 except HTTPError as e:
 735                     LOG.error(e.message)
 736                     server._error(e.status, content=e.content, stream=output)
 737             except ProcessingComplete:
 738                 pass
 739             else:
 740                 server.serve(url=url, page=page, stream=output)
 741
 742     s = scgi.scgi_server.SCGIServer(
 743         handler_class=GalleryHandler, host=host, port=port)
 744     LOG.info('serving SCGI on {}:{}'.format(host, port))
 745     s.serve()
 746
 747
 748 if __name__ == '__main__':
 749     import argparse as _argparse
 750
 751     parser = _argparse.ArgumentParser(
 752         description=__doc__, version=__version__,
 753         formatter_class=_argparse.RawDescriptionHelpFormatter)
 754     parser.add_argument(
 755         '--scgi', default=False, action='store_const', const=True,
 756         help='Run as a SCGI server (vs. serving a single CGI call)')
 757     parser.add_argument(
 758         '--port', default=4000, type=int,
 759         help='Port to listen to (if runing as a SCGI server)')
 760     parser.add_argument(
 761         '--base-path', default='.',
 762         help='Path to the root gallery source')
 763     parser.add_argument(
 764         '--base-url', default='/',
 765         help='URL for the root gallery source')
 766     parser.add_argument(
 767         '--shared-path', default=None,
 768         help=('Optional path to the shared directory containing '
 769               '`header.shtml` and `footer.shtml`'))
 770     parser.add_argument(
 771         '--cache-path', default='/tmp/gallery-cache',
 772         help='Path to the thumbnail and movie cache directory')
 773
 774     args = parser.parse_args()
 775
 776     s = CGIGalleryServer(
 777         base_path=args.base_path, base_url=args.base_url,
 778         cache_path=args.cache_path)
 779     if args.shared_path:
 780         shared = args.shared_path
 781         s.header = [open(_os_path.join(shared, 'header.shtml'), 'r').read()]
 782         s.footer = [open(_os_path.join(shared, 'footer.shtml'), 'r').read()]
 783
 784     if args.scgi:
 785         serve_scgi(server=s, port=args.port)
 786     else:
 787         serve_cgi(server=s)