bgneal@859: """
bgneal@859: ssl_images is a custom manage.py command to convert forum post and comment
bgneal@859: images to https. It does this by rewriting the markup:
bgneal@859:     - Images with src = http://surfguitar101.com/something are rewritten to be
bgneal@859:       /something.
bgneal@859:     - Non SG101 images that use http: are downloaded, resized, and uploaded to
bgneal@859:       an S3 bucket. The src attribute is replaced with the new S3 URL.
bgneal@859: """
bgneal@882: import base64
bgneal@859: import logging
bgneal@859: from optparse import make_option
bgneal@859: import os.path
bgneal@863: import re
bgneal@863: import signal
bgneal@881: import socket
bgneal@881: import urllib
bgneal@868: import urlparse
bgneal@881: import uuid
bgneal@859: 
bgneal@859: from django.core.management.base import NoArgsCommand, CommandError
bgneal@859: from django.conf import settings
bgneal@863: import markdown.inlinepatterns
bgneal@881: from PIL import Image
bgneal@859: 
bgneal@860: from comments.models import Comment
bgneal@860: from forums.models import Post
bgneal@881: from core.s3 import S3Bucket
bgneal@860: 
bgneal@860: 
bgneal@859: LOGFILE = os.path.join(settings.PROJECT_PATH, 'logs', 'ssl_images.log')
bgneal@859: logger = logging.getLogger(__name__)
bgneal@859: 
bgneal@871: IMAGE_LINK_RE = re.compile(markdown.inlinepatterns.IMAGE_LINK_RE,
bgneal@871:                            re.DOTALL | re.UNICODE)
bgneal@871: IMAGE_REF_RE = re.compile(markdown.inlinepatterns.IMAGE_REFERENCE_RE,
bgneal@871:                           re.DOTALL | re.UNICODE)
bgneal@863: 
bgneal@868: SG101_HOSTS = set(['www.surfguitar101.com', 'surfguitar101.com'])
bgneal@866: MODEL_CHOICES = ['comments', 'posts']
bgneal@866: 
bgneal@881: PHOTO_MAX_SIZE = (660, 720)
bgneal@881: PHOTO_BASE_URL = 'https://s3.amazonaws.com/'
bgneal@881: PHOTO_BUCKET_NAME = 'sg101.forum.photos'
bgneal@881: 
bgneal@863: quit_flag = False
bgneal@881: opener = None
bgneal@881: bucket = None
bgneal@881: url_cache = {}
bgneal@863: 
bgneal@863: 
bgneal@863: def signal_handler(signum, frame):
bgneal@863:     """SIGINT signal handler"""
bgneal@863:     global quit_flag
bgneal@863:     quit_flag = True
bgneal@863: 
bgneal@859: 
bgneal@859: def _setup_logging():
bgneal@859:     logger.setLevel(logging.DEBUG)
bgneal@859:     logger.propagate = False
bgneal@859:     handler = logging.FileHandler(filename=LOGFILE, encoding='utf-8')
bgneal@859:     formatter = logging.Formatter('%(asctime)s %(levelname)s %(message)s')
bgneal@859:     handler.setFormatter(formatter)
bgneal@859:     logger.addHandler(handler)
bgneal@859: 
bgneal@859: 
bgneal@881: class ImageURLopener(urllib.FancyURLopener):
bgneal@881:     """Our URL opener. Handles redirects as per FancyURLopener. But all other
bgneal@881:     errors and authentication requests will raise an IOError.
bgneal@881:     """
bgneal@881:     HANDLED_ERRORS = set([302, 301, 303, 307])
bgneal@881: 
bgneal@881:     def http_error_default(self, url, fp, errcode, errmsg, headers):
bgneal@881:         return urllib.URLopener.http_error_default(self, url, fp, errcode,
bgneal@881:                                                    errmsg, headers)
bgneal@881: 
bgneal@881:     def http_error(self, url, fp, errcode, errmsg, headers, data=None):
bgneal@881:         """Handle http errors.
bgneal@881:         We let FancyURLopener handle the redirects, but any other error we want
bgneal@881:         to let fail.
bgneal@881:         """
bgneal@881:         if errcode in self.HANDLED_ERRORS:
bgneal@881:             name = 'http_error_%d' % errcode
bgneal@881:             method = getattr(self, name)
bgneal@881:             if data is None:
bgneal@881:                 result = method(url, fp, errcode, errmsg, headers)
bgneal@881:             else:
bgneal@881:                 result = method(url, fp, errcode, errmsg, headers, data)
bgneal@881:             if result:
bgneal@881:                 return result
bgneal@881:         return self.http_error_default(url, fp, errcode, errmsg, headers)
bgneal@881: 
bgneal@881: 
bgneal@881: def download_image(src):
bgneal@881:     """Downloads the image file from the given source URL.
bgneal@881: 
bgneal@881:     If successful returns the path to the downloaded file. Otherwise None is
bgneal@881:     returned.
bgneal@881:     """
bgneal@881:     logger.info("Retrieving %s", src)
bgneal@881:     try:
bgneal@881:         fn, hdrs = opener.retrieve(src)
bgneal@881:     except IOError as ex:
bgneal@881:         args = ex.args
bgneal@881:         if len(args) == 4 and args[0] == 'http error':
bgneal@881:             logger.error("http error: %d - %s", args[1], args[2])
bgneal@881:         else:
bgneal@881:             logger.error("%s", ex)
bgneal@881:         return None
bgneal@881: 
bgneal@887:     # TODO: This code below is not right. content-length is optional and will
bgneal@887:     # not appear when using chunked encoding, for example. Remove this check. If
bgneal@887:     # we want to log the size of the file, use stat() on it or something.
bgneal@887:     #
bgneal@881:     # If there is an error or timeout, sometimes there is no content-length
bgneal@881:     # header.
bgneal@881:     content_length = hdrs.get('content-length')
bgneal@881:     if not content_length:
bgneal@881:         logger.error("Bad content-length: %s", content_length)
bgneal@881:         return None
bgneal@881: 
bgneal@881:     # Does it look like an image?
bgneal@881:     content_type = hdrs.get('content-type')
bgneal@881:     if not content_type:
bgneal@881:         logger.error("No content-type header found")
bgneal@881:         return None
bgneal@881: 
bgneal@881:     logger.info("Retrieved: %s bytes; content-type: %s", content_length,
bgneal@881:                  content_type)
bgneal@881: 
bgneal@881:     parts = content_type.split('/')
bgneal@881:     if len(parts) < 2 or parts[0] != 'image':
bgneal@881:         logger.error("Unknown content-type: %s", content_type)
bgneal@881:         return None
bgneal@881: 
bgneal@881:     return fn
bgneal@881: 
bgneal@881: 
bgneal@881: def resize_image(img_path):
bgneal@881:     """Resizes the image found at img_path if necessary."""
bgneal@881:     image = Image.open(img_path)
bgneal@881:     if image.size > PHOTO_MAX_SIZE:
bgneal@881:         logger.info('Resizing from %s to %s', image.size, PHOTO_MAX_SIZE)
bgneal@881:         image.thumbnail(PHOTO_MAX_SIZE, Image.ANTIALIAS)
bgneal@881:         image.save(img_path)
bgneal@881: 
bgneal@881: 
bgneal@882: def gen_key():
bgneal@882:     """Return a random key."""
bgneal@882:     return base64.b64encode(uuid.uuid4().bytes, '-_').rstrip('=')
bgneal@882: 
bgneal@882: 
bgneal@881: def upload_image(img_path):
bgneal@881:     """Upload image file located at img_path to our S3 bucket.
bgneal@881: 
bgneal@881:     Returns the URL of the image in the bucket or None if an error occurs.
bgneal@881:     """
bgneal@881:     logger.info("upload_image starting")
bgneal@881:     # Make a unique name for the image in the bucket
bgneal@881:     ext = os.path.splitext(img_path)[1]
bgneal@882:     file_key = gen_key() + ext
bgneal@881:     try:
bgneal@881:         return bucket.upload_from_filename(file_key, img_path, public=True)
bgneal@881:     except IOError as ex:
bgneal@881:         logger.error("Error uploading file: %s", ex)
bgneal@881:     return None
bgneal@881: 
bgneal@881: 
bgneal@868: def save_image_to_cloud(src):
bgneal@881:     """Downloads an image at a given source URL. Uploads it to cloud storage.
bgneal@881: 
bgneal@881:     Returns the new URL or None if unsuccessful.
bgneal@881:     """
bgneal@881:     # Check the cache first
bgneal@881:     new_url = url_cache.get(src)
bgneal@881:     if new_url:
bgneal@881:         return new_url
bgneal@881: 
bgneal@881:     fn = download_image(src)
bgneal@881:     if fn:
bgneal@881:         resize_image(fn)
bgneal@881:         new_url = upload_image(fn)
bgneal@881:         if new_url:
bgneal@881:             url_cache[src] = new_url
bgneal@881:         return new_url
bgneal@881:     return None
bgneal@868: 
bgneal@868: 
bgneal@866: def replace_image_markup(match):
bgneal@870:     src_parts = match.group(8).split()
bgneal@868:     if src_parts:
bgneal@868:         src = src_parts[0]
bgneal@868:         if src[0] == "<" and src[-1] == ">":
bgneal@868:             src = src[1:-1]
bgneal@868:     else:
bgneal@868:         src = ''
bgneal@868: 
bgneal@868:     title = ''
bgneal@868:     if len(src_parts) > 1:
bgneal@868:         title = " ".join(src_parts[1:])
bgneal@870:     alt = match.group(1)
bgneal@868: 
bgneal@871:     new_src = None
bgneal@868:     if src:
bgneal@868:         r = urlparse.urlparse(src)
bgneal@871:         if r.hostname in SG101_HOSTS:
bgneal@871:             new_src = r.path        # convert to relative path
bgneal@871:         elif r.scheme == 'http':
bgneal@887:             # TODO: it has been observed that at least 2 different services
bgneal@887:             # serve up the same image on https: with the URL otherwise the same.
bgneal@887:             # Add code to see if the image is available at https (maybe do
bgneal@887:             # a HEAD request?) and if so just change the protocol to https in
bgneal@887:             # the original URL.
bgneal@871:             new_src = save_image_to_cloud(src)
bgneal@868:         elif r.scheme == 'https':
bgneal@868:             new_src = src       # already https, accept it as-is
bgneal@868: 
bgneal@868:     if new_src:
bgneal@868:         if title:
bgneal@871:             s = u'![{alt}]({src} {title})'.format(alt=alt, src=new_src, title=title)
bgneal@868:         else:
bgneal@868:             s = u'![{alt}]({src})'.format(alt=alt, src=new_src)
bgneal@868:     else:
bgneal@868:         # something's messed up, convert to a link using original src
bgneal@868:         s = u'[{alt}]({src})'.format(alt=alt, src=src)
bgneal@868: 
bgneal@868:     return s
bgneal@860: 
bgneal@860: 
bgneal@887: def warn_if_image_refs(text, model_name, pk):
bgneal@887:     """Search text for Markdown image reference markup.
bgneal@887: 
bgneal@887:     We aren't expecting these, but we will log something if we see any.
bgneal@887:     """
bgneal@887:     if IMAGE_REF_RE.search(text):
bgneal@887:         logger.warning("Image reference found in %s pk = #%d", model_name, pk)
bgneal@887: 
bgneal@887: 
bgneal@866: def process_post(text):
bgneal@863:     """Process the post object:
bgneal@863: 
bgneal@863:     A regex substitution is run on the post's text field. This fixes up image
bgneal@863:     links, getting rid of plain old http sources; either converting to https
bgneal@863:     or relative style links (if the link is to SG101).
bgneal@863: 
bgneal@863:     """
bgneal@866:     return IMAGE_LINK_RE.sub(replace_image_markup, text)
bgneal@863: 
bgneal@863: 
bgneal@859: class Command(NoArgsCommand):
bgneal@859:     help = "Rewrite forum posts and comments to not use http for images"
bgneal@859:     option_list = NoArgsCommand.option_list + (
bgneal@866:             make_option('-m', '--model',
bgneal@866:                 choices=MODEL_CHOICES,
bgneal@866:                 help="which model to update; must be one of {{{}}}".format(
bgneal@866:                                                     ', '.join(MODEL_CHOICES))),
bgneal@860:             make_option('-i', '--i',
bgneal@859:                 type='int',
bgneal@863:                 help="optional first slice index; the i in [i:j]"),
bgneal@860:             make_option('-j', '--j',
bgneal@859:                 type='int',
bgneal@863:                 help="optional second slice index; the j in [i:j]"),
bgneal@859:             )
bgneal@859: 
bgneal@859:     def handle_noargs(self, **options):
bgneal@859:         _setup_logging()
bgneal@860:         logger.info("Starting; arguments received: %s", options)
bgneal@859: 
bgneal@866:         if options['model'] not in MODEL_CHOICES:
bgneal@866:             raise CommandError('Please choose a --model option')
bgneal@859: 
bgneal@866:         if options['model'] == 'comments':
bgneal@860:             qs = Comment.objects.all()
bgneal@866:             text_attr = 'comment'
bgneal@881:             model_name = 'Comment'
bgneal@860:         else:
bgneal@860:             qs = Post.objects.all()
bgneal@866:             text_attr = 'body'
bgneal@881:             model_name = 'Post'
bgneal@860: 
bgneal@860:         i, j = options['i'], options['j']
bgneal@860: 
bgneal@860:         if i is not None and i < 0:
bgneal@860:             raise CommandError("-i must be >= 0")
bgneal@860:         if j is not None and j < 0:
bgneal@860:             raise CommandError("-j must be >= 0")
bgneal@860:         if j is not None and i is not None and j <= i:
bgneal@860:             raise CommandError("-j must be > -i")
bgneal@860: 
bgneal@860:         if i is not None and j is not None:
bgneal@860:             qs = qs[i:j]
bgneal@860:         elif i is not None and j is None:
bgneal@860:             qs = qs[i:]
bgneal@860:         elif i is None and j is not None:
bgneal@860:             qs = qs[:j]
bgneal@860: 
bgneal@881:         # Set global socket timeout
bgneal@881:         socket.setdefaulttimeout(30)
bgneal@881: 
bgneal@863:         # Install signal handler for ctrl-c
bgneal@863:         signal.signal(signal.SIGINT, signal_handler)
bgneal@863: 
bgneal@881:         # Create URL opener to download photos
bgneal@881:         global opener
bgneal@881:         opener = ImageURLopener()
bgneal@881: 
bgneal@881:         # Create bucket to upload photos
bgneal@881:         global bucket
bgneal@881:         bucket = S3Bucket(access_key=settings.USER_PHOTOS_ACCESS_KEY,
bgneal@881:                           secret_key=settings.USER_PHOTOS_SECRET_KEY,
bgneal@881:                           base_url=PHOTO_BASE_URL,
bgneal@881:                           bucket_name=PHOTO_BUCKET_NAME)
bgneal@887: 
bgneal@887:         if i is None:
bgneal@887:             i = 0
bgneal@887: 
bgneal@881:         for n, model in enumerate(qs.iterator()):
bgneal@863:             if quit_flag:
bgneal@863:                 logger.warning("SIGINT received, exiting")
bgneal@881:                 break
bgneal@881:             logger.info("Processing %s #%d (pk = %d)", model_name, n + i, model.pk)
bgneal@866:             txt = getattr(model, text_attr)
bgneal@887:             warn_if_image_refs(txt, model_name, model.pk)
bgneal@866:             new_txt = process_post(txt)
bgneal@881:             if txt != new_txt:
bgneal@887:                 logger.info("Content changed on %s #%d (pk= %d)",
bgneal@887:                             model_name, n + i, model.pk)
bgneal@881:                 logger.debug("original: %s", txt)
bgneal@881:                 logger.debug("changed:  %s", new_txt)
bgneal@887:                 setattr(model, text_attr, new_txt)
bgneal@887:                 model.save()
bgneal@860: 
bgneal@887:         logger.info("ssl_images exiting")