From: W. Trevor King Date: Sat, 25 Aug 2012 13:55:24 +0000 (-0400) Subject: Allow gallery.py to serve original images. X-Git-Url: http://git.tremily.us/?a=commitdiff_plain;h=ebd0292d;p=blog.git Allow gallery.py to serve original images. This reworks some of the internals to clean up URL validation and error handling. Rather than pass `stream` around, we raise the new HTTPError wherever we want. These errors are caught and dealt with higher up, so low level internal functions don't need to care. That way I don't get nervous the next time I forget about ProcessingComplete ;). --- diff --git a/posts/gallery/gallery.py b/posts/gallery/gallery.py index 34a51ce..7d44b77 100755 --- a/posts/gallery/gallery.py +++ b/posts/gallery/gallery.py @@ -32,7 +32,7 @@ CGI gallery server for a picture directory organized along:: With:: - pics$ gallery.py some_directory another_directory + pics$ gallery.py Note that you can store a caption for ```` as plain text in ``.txt``. @@ -46,6 +46,7 @@ This script can also be run as a Simple Common Gateway Interface import logging as _logging import logging.handlers as _logging_handlers import math as _math +import mimetypes as _mimetypes import os as _os import os.path as _os_path import random as _random @@ -58,6 +59,7 @@ __version__ = '0.5' IMAGE_EXTENSIONS = ['.jpg', '.jpeg', '.tif', '.tiff', '.png', '.gif'] VIDEO_EXTENSIONS = ['.mov', '.mp4', '.ogv'] +STREAMING_TYPES = ['video/ogg'] RESPONSES = { # httplib takes half a second to load 200: 'OK', 404: 'Not Found', @@ -76,13 +78,23 @@ class CommandError(Exception): def __init__(self, command, status, stdout=None, stderr=None): strerror = ['Command failed (%d):\n %s\n' % (status, stderr), 'while executing\n %s' % str(command)] - Exception.__init__(self, '\n'.join(strerror)) + super(CommandError, self).__init__('\n'.join(strerror)) self.command = command self.status = status self.stdout = stdout self.stderr = stderr +class HTTPError(Exception): + def __init__(self, status, message=None, content=None): + if message is None: + message = RESPONSES[status] + super(HTTPError, self).__init__('{} {}'.format(status, message)) + self.status = status + self.message = message + self.content = content + + class ProcessingComplete(Exception): pass @@ -110,7 +122,13 @@ def invoke(args, stdin=None, stdout=_subprocess.PIPE, stderr=_subprocess.PIPE, raise CommandError(args, status, stdout, stderr) return status, stdout, stderr -def is_picture(filename): +def is_image(filename): + for extension in IMAGE_EXTENSIONS: + if filename.lower().endswith(extension): + return True + return False + +def is_video(filename): for extension in IMAGE_EXTENSIONS: if filename.lower().endswith(extension): return True @@ -123,13 +141,15 @@ def image_base(filename): class CGIGalleryServer (object): - def __init__(self, base_path='/var/www/localhost/htdocs/gallery/', - base_url='/cgi-bin/gallery.py', - cache_path='/tmp/gallery-cache/'): + def __init__(self, base_path='.', + base_url='/', + cache_path='/tmp/gallery-cache/', + serve_originals=True): self._base_path = _os_path.abspath(base_path) self._base_url = base_url self._cache_path = cache_path - self._url_regexp = _re.compile('^[a-z0-9._/-]*$') + self._serve_originals = serve_originals + self._url_regexp = _re.compile('^[a-zA-Z0-9._/-]*$') self._rows = 3 self._columns = 3 self.header = [] @@ -175,8 +195,9 @@ class CGIGalleryServer (object): content = RESPONSES[status] self._response(header=header, content=content, stream=stream) - def validate_url(self, url, stream=None): - LOG.debug('validating {}'.format(repr(url))) + def validate_url(self, url, exists=True, directory=False): + LOG.debug('validating {} (exists={}, directory={})'.format( + repr(url), exists, directory)) if url is None: return elif (not self._url_regexp.match(url) or @@ -184,39 +205,46 @@ class CGIGalleryServer (object): '..' in url ): LOG.error('invalid url') - self._error(404, stream=stream) - path = _os_path.join(self._base_path, url) - if _os_path.exists(path) and not _os_path.isdir(path): - LOG.error('nonexistent directory') - self._error(404, stream=stream) + raise HTTPError(404) + if exists: + path = _os_path.join(self._base_path, url) + if directory: + if not _os_path.isdir(path): + LOG.error('nonexistent directory') + raise HTTPError(404) + else: + if not _os_path.isfile(path): + raise HTTPError(404, 'nonexistent file') def serve(self, url=None, page=0, stream=None): LOG.info('serving url {} (page {})'.format(url, page)) try: - if url is None: - self.index(stream=stream) - elif url.endswith('random'): - self.random( - url=url, stream=stream, max_width=500, max_height=500) - elif self.is_cached(url=url): - self.cached(url=url, stream=stream) - elif url.endswith('.png'): - self._thumb(url=url, stream=stream) - else: - self.validate_url(url=url, stream=stream) - self.page(url=url, page=page, stream=stream) - LOG.error('unexpected url type') - self._error(404, stream=stream) + try: + if url is None: + self.index(stream=stream) + elif url.endswith('random'): + self.random( + url=url, stream=stream, max_width=500, max_height=500) + elif self.is_cacheable(url=url): + self.validate_url(url=url, exists=False) + self.cached(url=url, stream=stream) + else: + self.validate_url(url=url, exists=False, directory=True) + self.page(url=url, page=page, stream=stream) + raise HTTPError(404, 'unexpected URL type') + except HTTPError as e: + LOG.error(e.message) + self._error(e.status, content=e.content, stream=stream) except ProcessingComplete: pass - def relative_url(self, url, stream=None): + def relative_url(self, url): if url is None: return url if not url.startswith(self._base_url): - LOG.error('cannot convert {} to a relative URL of {}'.format( - url, self._base_url)) - return self._error(404, stream=stream) + message = 'cannot convert {} to a relative URL of {}'.format( + url, self._base_url) + raise HTTPError(404, message) if url == self._base_url: return None return url[len(self._base_url):] @@ -263,14 +291,44 @@ class CGIGalleryServer (object): if p.startswith('.') or p.endswith('~'): continue picture_path = _os_path.join(path, p) - if is_picture(picture_path): + if is_image(picture_path): yield picture_path def index(self, stream=None): LOG.debug('index page') return self._directory(self._base_path, stream=stream) - def _thumb(self, image, max_width=None, max_height=None, stream=None): + def _original_url(self, url): + """Reverse thumbnail URL mapping + + Returns (original_url, generating_callback, callback_kwargs). + """ + base,extension = _os_path.splitext(url) + if extension in ['.png']: + try: + root,width,height = base.rsplit('-', 2) + except ValueError: + raise HTTPError(404, 'missing width/height in {}'.format(base)) + try: + width = int(width) + height = int(height) + except ValueError as e: + raise HTTPError(404, 'invalid width/height: {}'.format(e)) + return ( + root + '.jpg', + self._thumb, + {'max_width': width, + 'max_height': height}, + ) + elif extension in VIDEO_EXTENSIONS: + return ( + base + '.mov', + getattr(self, '_{}'.format(extension), None), + {}, + ) + raise HTTPError(404, 'no original URL for {}'.format(url)) + + def _thumb(self, image, max_width=None, max_height=None): if not _os_path.exists(self._cache_path): _os.makedirs(self._cache_path) dirname,filename = _os_path.split(image) @@ -284,19 +342,18 @@ class CGIGalleryServer (object): thumb_path = _os_path.join(cache_dir, thumb_filename) image_path = _os_path.join(self._base_path, image) if not _os_path.isfile(image_path): - LOG.error('image path for thumbnail does not exist') - return self._error(404, stream=stream) + raise HTTPError(404, 'image path for thumbnail does not exist') if (not _os_path.isfile(thumb_path) or _os_path.getmtime(image_path) > _os_path.getmtime(thumb_path)): invoke(['convert', '-format', 'png', '-strip', '-quality', '95', image_path, '-thumbnail', '{:d}x{:d}'.format(max_width, max_height), thumb_path]) - return thumb_url + return (thumb_path, self._url(thumb_url)) - def _mp4(self, video, stream=None): + def _mp4(self, video): if not video.endswith('.mov'): - LOG.error("can't translate {} to MPEGv4".format(video)) + raise HTTPError(404, "can't translate {} to MPEGv4".format(video)) dirname,filename = _os_path.split(video) mp4_filename = image_base(filename) + '.mp4' reldir = _os_path.relpath(dirname, self._base_path) @@ -306,8 +363,7 @@ class CGIGalleryServer (object): mp4_url = _os_path.join(dirname, mp4_filename) mp4_path = _os_path.join(cache_dir, mp4_filename) if not _os_path.isfile(video): - LOG.error('source video path does not exist') - return self._error(404, stream=stream) + raise HTTPError(404, 'source video path does not exist') if (not _os_path.isfile(mp4_path) or _os_path.getmtime(video) > _os_path.getmtime(mp4_path)): arg = ['ffmpeg', '-i', video, '-acodec', 'libfaac', '-aq', '200', @@ -317,7 +373,7 @@ class CGIGalleryServer (object): arg.extend(args) arg.append(mp4_path) invoke(arg) - return self._url(mp4_url) + return (mp4_path, self._url(mp4_url)) def _ogv(self, video, stream=None): if not video.endswith('.mov'): @@ -332,14 +388,13 @@ class CGIGalleryServer (object): ogv_path = _os_path.join(cache_dir, ogv_filename) if not _os_path.isfile(video): LOG.error('source video path does not exist') - return self._error(404, stream=stream) if (not _os_path.isfile(ogv_path) or _os_path.getmtime(video) > _os_path.getmtime(ogv_path)): arg = ['ffmpeg2theora', '--optimize'] arg.extend(args) arg.extend(['--output', ogv_path, video]) invoke(arg) - return self._url(ogv_url) + return (ogv_path, self._url(ogv_url)) def _get_image_caption(self, path): caption_path = path + '.txt' @@ -348,19 +403,18 @@ class CGIGalleryServer (object): except IOError: return None - def _get_image_video(self, path, fallback=None, stream=None): + def _get_image_video(self, path, fallback=None): base_path = image_base(path) for extension in VIDEO_EXTENSIONS: video_path = base_path + extension if _os_path.isfile(video_path): - return self._video( - video_path, fallback=fallback, stream=stream) + return self._video(video_path, fallback=fallback) return None - def _captioned_video(self, path, href=None, stream=None): - img = self._image(path, max_width=640, max_height=480, stream=stream) + def _captioned_video(self, path, href=None): + img = self._image(path, max_width=640, max_height=480) caption = self._get_image_caption(path) - video = self._get_image_video(path, fallback=[img], stream=stream) + video = self._get_image_video(path, fallback=[img]) content = [] if video: content.extend(video) @@ -375,7 +429,7 @@ class CGIGalleryServer (object): content.append('

{}

'.format(caption)) return content - def _video(self, video, fallback=None, stream=None, **kwargs): + def _video(self, video, fallback=None, **kwargs): if fallback is None: fallback = [ '

Your browser does not support the <video> tag, try', @@ -383,31 +437,31 @@ class CGIGalleryServer (object): '

', ] fallback = [' '+line for line in fallback] - ogv = self._ogv(video, stream=stream) - mp4 = self._mp4(video, stream=stream) + ogv_path,ogv_url = self._ogv(video) + mp4_path,mp4_url = self._mp4(video) return [ '

', (' ', '

', '

Download as', - ' Ogg/Theora/Vorbis or'.format(ogv), + ' Ogg/Theora/Vorbis or'.format(ogv_url), (' Mpeg4/H.264(ConstrainedBaselineProfile)/AAC.' - ).format(mp4), + ).format(mp4_url), '

', ] def _image(self, image, **kwargs): if kwargs: - image = self._thumb(image, **kwargs) - return ''.format(self._url(image)) + image_path,image_url = self._thumb(image, **kwargs) + return ''.format(image_url) def _image_page(self, image): return image_base(image) + '/' @@ -415,16 +469,17 @@ class CGIGalleryServer (object): def random(self, url=None, stream=None, **kwargs): LOG.debug('random image') if url.endswith('/random'): - base_dir = _os_path.join( - self._base_path, url[:(-len('/random'))]) + url = url[:(-len('/random'))] + self.validate_url(url=url, directory=True, stream=stream) + base_dir = _os_path.join(self._base_path, url) elif url == 'random': base_dir = self._base_path else: - self._error(404, stream=stream) + raise HTTPError(404) images = [] for dirpath,dirnames,filenames in _os.walk(base_dir): for filename in filenames: - if is_picture(filename): + if is_image(filename): images.append(_os_path.join(dirpath, filename)) if not images: self._response(content='

no images to choose from

', @@ -432,44 +487,50 @@ class CGIGalleryServer (object): image = _random.choice(images) LOG.debug('selected random image {}'.format(image)) page = self._image_page(image) - content = self._captioned_video(path=image, href=page, stream=stream) + content = self._captioned_video(path=image, href=page) self._response(content='\n'.join(content), stream=stream) - def is_cached(self, url): - for extension in ['.png', '.mp4', '.ogv']: - if url.endswith(extension): - return True - return False + def is_cacheable(self, url): + return is_image(url) or is_video(url) def cached(self, url, stream=None): - LOG.debug('retrieving cached item') - if url.endswith('.png'): - mime = 'image/png' - elif url.endswith('.ogv'): - mime = 'video/ogg' - elif url.endswith('.mp4'): - mime = 'video/mp4' - else: - raise NotImplementedError() - header = self._http_header(mime=mime) + LOG.debug('retrieving possibly cached item') + mime = _mimetypes.guess_type(url)[0] + if mime is None: + raise HTTPError(404, 'unknown mime type for {}'.format(url)) cache_path = _os_path.join(self._cache_path, url) + original_path = _os_path.join(self._base_path, url) + path = None + if _os_path.isfile(cache_path): + LOG.debug('return cached item {}'.format(cache_path)) + path = cache_path + elif self._serve_originals and _os_path.isfile(original_path): + LOG.debug('return original item {}'.format(original_path)) + path = original_path + else: + LOG.debug('possibly create cached item {}'.format(cache_path)) + original_url,callback,kwargs = self._original_url(url) + original_path = _os_path.join(self._base_path, original_url) + if callback and _os_path.isfile(original_path): + path,cache_url = callback(original_path, **kwargs) + if not path: + raise HTTPError(404) try: - content = open(cache_path, 'rb') - except IOError, e: - LOG.error('invalid url') + content = open(path, 'rb') + except IOError as e: LOG.error(e) - self._error(404, stream=stream) - if mime in ['video/ogg']: + raise HTTPError(404, 'item not found {}'.format(url)) + header = self._http_header(mime=mime) + if mime in STREAMING_TYPES: self._response_stream( header=header, content=content, stream=stream) content = content.read() self._response(header=header, content=content, stream=stream) def page(self, url, page=0, stream=None): - LOG.debug('HTML page') + LOG.debug('HTML page {} {}'.format(url, page)) if not url.endswith('/'): - LOG.error('HTML page URLs must end with a slash') - self._error(404, stream=stream) + raise HTTPError(404, 'HTML page URLs must end with a slash') abspath = _os_path.join(self._base_path, url) if _os_path.isdir(abspath): self._directory(path=abspath, page=page, stream=stream) @@ -477,8 +538,7 @@ class CGIGalleryServer (object): file_path = abspath[:-1] + extension if _os_path.isfile(file_path): self._page(path=file_path, stream=stream) - LOG.debug('unknown HTML page') - self._error(404, stream=stream) + raise HTTPError(404, 'unknown HTML page {}'.format(url)) def _directory_header(self, path): relpath = _os_path.relpath(path, self._base_path) @@ -531,13 +591,12 @@ class CGIGalleryServer (object): content.append('') return content - def _directory_images(self, path, images, stream=None): + def _directory_images(self, path, images): content = [''] column = 0 for image in images: page = self._image_page(image) - img = self._image( - image, max_width=300, max_height=300, stream=stream) + img = self._image(image, max_width=300, max_height=300) link = self._link(page, img) if column == 0: content.append(' ') @@ -557,15 +616,15 @@ class CGIGalleryServer (object): return content def _directory(self, path, page=0, stream=None): - LOG.debug('directory page') + LOG.debug('directory page {} {}'.format(path, page)) images = list(self._images(path)) images_per_page = self._rows * self._columns pages = int(_math.ceil(float(len(images)) / images_per_page)) or 1 if page < 0 or page >= pages: - LOG.error( + raise HTTPError( + 404, 'page out of bounds for this gallery 0 <= {:d} < {:d}'.format( page, pages)) - self._error(404, stream=stream) first_image = images_per_page * page images = images[first_image:first_image+images_per_page] content = [] @@ -574,14 +633,13 @@ class CGIGalleryServer (object): nav = self._directory_page_navigation(path, page=page, pages=pages) content.extend(nav) content.extend(self._directory_subdirs(path)) - content.extend(self._directory_images( - path, images=images, stream=stream)) + content.extend(self._directory_images(path, images=images)) content.extend(nav) content.extend(self.footer) self._response(content='\n'.join(content), stream=stream) def _page(self, path, stream=None): - LOG.debug('image page') + LOG.debug('image page {}'.format(path)) gallery = _os_path.dirname(path) images = list(self._images(gallery)) images_per_page = self._rows * self._columns @@ -600,7 +658,7 @@ class CGIGalleryServer (object): self._link(next_page, 'next'), '

', ]) - content.extend(self._captioned_video(path, stream=stream)) + content.extend(self._captioned_video(path)) content.append('') content.extend(self.footer) self._response(content='\n'.join(content), stream=stream) @@ -648,7 +706,11 @@ def serve_scgi(server, host='localhost', port=4000): except ValueError: pass try: - url = server.relative_url(url=url, stream=output) + try: + url = server.relative_url(url=url) + except HTTPError as e: + LOG.error(e.message) + server._error(e.status, content=e.content, stream=stream) except ProcessingComplete: pass else: