# Based on https://github.com/richardbarran/django-photologue/
# by Richard Barran, BSD-3 licensed
import logging
import os
import random
import unicodedata
from datetime import datetime
from functools import partial
from importlib import import_module
from inspect import isclass
from io import BytesIO
import exifread
from django.conf import settings
from django.core.exceptions import ValidationError
from django.core.files.base import ContentFile
from django.core.files.storage import default_storage
from django.core.validators import RegexValidator
from django.db import models
from django.template.defaultfilters import slugify
from django.urls import reverse
from django.utils.encoding import filepath_to_uri, force_str, smart_str
from django.utils.safestring import mark_safe
from django.utils.timezone import now
from django.utils.translation import gettext_lazy as _
from PIL import Image, ImageFile, ImageFilter
logger = logging.getLogger('photologue.models')
# Default limit for gallery.latest
LATEST_LIMIT = getattr(settings, 'PHOTOLOGUE_GALLERY_LATEST_LIMIT', None)
# max_length setting for the ImageModel ImageField
IMAGE_FIELD_MAX_LENGTH = getattr(settings, 'PHOTOLOGUE_IMAGE_FIELD_MAX_LENGTH', 100)
# Modify image file buffer size.
ImageFile.MAXBLOCK = getattr(settings, 'PHOTOLOGUE_MAXBLOCK', 256 * 2 ** 10)
# Look for user function to define file paths
PHOTOLOGUE_PATH = getattr(settings, 'PHOTOLOGUE_PATH', None)
if PHOTOLOGUE_PATH is not None:
if callable(PHOTOLOGUE_PATH):
get_storage_path = PHOTOLOGUE_PATH
else:
parts = PHOTOLOGUE_PATH.split('.')
module_name = '.'.join(parts[:-1])
module = import_module(module_name)
get_storage_path = getattr(module, parts[-1])
else:
def get_storage_path(instance, filename):
fn = unicodedata.normalize('NFKD', force_str(filename)).encode('ascii', 'ignore').decode('ascii')
return os.path.join('photos', fn)
# Support CACHEDIR.TAG spec for backups for ignoring cache dir.
# See http://www.brynosaurus.com/cachedir/spec.html
PHOTOLOGUE_CACHEDIRTAG = os.path.join("photos", "cache", "CACHEDIR.TAG")
if not default_storage.exists(PHOTOLOGUE_CACHEDIRTAG):
default_storage.save(PHOTOLOGUE_CACHEDIRTAG, ContentFile(
b"Signature: 8a477f597d28d172789f06886806bc55"))
# Exif Orientation values
# Value 0thRow 0thColumn
# 1 top left
# 2 top right
# 3 bottom right
# 4 bottom left
# 5 left top
# 6 right top
# 7 right bottom
# 8 left bottom
# Image Orientations (according to EXIF informations) that needs to be
# transposed and appropriate action
IMAGE_EXIF_ORIENTATION_MAP = {
2: Image.FLIP_LEFT_RIGHT,
3: Image.ROTATE_180,
6: Image.ROTATE_270,
8: Image.ROTATE_90,
}
# Quality options for JPEG images
JPEG_QUALITY_CHOICES = (
(30, _('Very Low')),
(40, _('Low')),
(50, _('Medium-Low')),
(60, _('Medium')),
(70, _('Medium-High')),
(80, _('High')),
(90, _('Very High')),
)
# choices for new crop_anchor field in Photo
CROP_ANCHOR_CHOICES = (
('top', _('Top')),
('right', _('Right')),
('bottom', _('Bottom')),
('left', _('Left')),
('center', _('Center (Default)')),
)
IMAGE_TRANSPOSE_CHOICES = (
('FLIP_LEFT_RIGHT', _('Flip left to right')),
('FLIP_TOP_BOTTOM', _('Flip top to bottom')),
('ROTATE_90', _('Rotate 90 degrees counter-clockwise')),
('ROTATE_270', _('Rotate 90 degrees clockwise')),
('ROTATE_180', _('Rotate 180 degrees')),
)
# Prepare a list of image filters
filter_names = []
for n in dir(ImageFilter):
klass = getattr(ImageFilter, n)
if isclass(klass) and issubclass(klass, ImageFilter.BuiltinFilter) and \
hasattr(klass, 'name'):
filter_names.append(klass.__name__)
IMAGE_FILTERS_HELP_TEXT = _('Chain multiple filters using the following pattern "FILTER_ONE->FILTER_TWO->FILTER_THREE"'
'. Image filters will be applied in order. The following filters are available: %s.'
% (', '.join(filter_names)))
size_method_map = {}
class TagField(models.CharField):
"""Tags have been removed from Photologue, but the migrations still refer to them so this
Tagfield definition is left here.
"""
def __init__(self, **kwargs):
default_kwargs = {'max_length': 255, 'blank': True}
default_kwargs.update(kwargs)
super().__init__(**default_kwargs)
def get_internal_type(self):
return 'CharField'
class Gallery(models.Model):
date_added = models.DateTimeField(_('date published'),
default=now)
title = models.CharField(_('title'),
max_length=250,
unique=True)
slug = models.SlugField(_('title slug'),
unique=True,
max_length=250,
help_text=_('A "slug" is a unique URL-friendly title for an object.'))
description = models.TextField(_('description'),
blank=True)
is_public = models.BooleanField(_('is public'),
default=True,
help_text=_('Public galleries will be displayed '
'in the default views.'))
photos = models.ManyToManyField('photologue.Photo',
related_name='galleries',
verbose_name=_('photos'),
blank=True)
class Meta:
ordering = ['-date_added']
get_latest_by = 'date_added'
verbose_name = _('gallery')
verbose_name_plural = _('galleries')
def __str__(self):
return self.title
def get_absolute_url(self):
return reverse('photologue:pl-gallery', args=[self.slug])
def latest(self, limit=LATEST_LIMIT, public=True):
if not limit:
limit = self.photo_count()
if public:
return self.public()[:limit]
else:
return self.photos[:limit]
def sample(self, count=None, public=True):
"""Return a sample of photos, ordered at random."""
if not count:
count = 1
if count > self.photo_count():
count = self.photo_count()
if public:
photo_set = self.public()
else:
photo_set = self.photos
return random.sample(set(photo_set), count)
def photo_count(self, public=True):
"""Return a count of all the photos in this gallery."""
if public:
return self.public().count()
else:
return self.photos.count()
photo_count.short_description = _('count')
def public(self):
"""Return a queryset of all the public photos in this gallery."""
return self.photos.filter(is_public=True)
class ImageModel(models.Model):
image = models.ImageField(_('image'),
max_length=IMAGE_FIELD_MAX_LENGTH,
upload_to=get_storage_path)
date_taken = models.DateTimeField(_('date taken'),
null=True,
blank=True,
help_text=_('Date image was taken; is obtained from the image EXIF data.'))
view_count = models.PositiveIntegerField(_('view count'),
default=0,
editable=False)
crop_from = models.CharField(_('crop from'),
blank=True,
max_length=10,
default='center',
choices=CROP_ANCHOR_CHOICES)
class Meta:
abstract = True
def exif(self, file=None):
try:
if file:
tags = exifread.process_file(file)
else:
with self.image.storage.open(self.image.name, 'rb') as file:
tags = exifread.process_file(file, details=False)
return tags
except Exception:
return {}
def admin_thumbnail(self):
func = getattr(self, 'get_admin_thumbnail_url', None)
if func is None:
return _('An "admin_thumbnail" photo size has not been defined.')
else:
if hasattr(self, 'get_absolute_url'):
return mark_safe('
'.format(self.get_absolute_url(), func()))
else:
return mark_safe(''.format(self.image.url, func()))
admin_thumbnail.short_description = _('Thumbnail')
admin_thumbnail.allow_tags = True
def cache_path(self):
return os.path.join(os.path.dirname(self.image.name), "cache")
def cache_url(self):
return '/'.join([os.path.dirname(self.image.url), "cache"])
def image_filename(self):
return os.path.basename(force_str(self.image.name))
def _get_filename_for_size(self, size):
size = getattr(size, 'name', size)
base, ext = os.path.splitext(self.image_filename())
return ''.join([base, '_', size, ext])
def _get_size_photosize(self, size):
return PhotoSizeCache().sizes.get(size)
def _get_size_size(self, size):
photosize = PhotoSizeCache().sizes.get(size)
if not self.size_exists(photosize):
self.create_size(photosize)
try:
return Image.open(self.image.storage.open(
self._get_size_filename(size))).size
except Exception:
return None
def _get_size_url(self, size):
photosize = PhotoSizeCache().sizes.get(size)
if not self.size_exists(photosize):
self.create_size(photosize)
if photosize.increment_count:
self.increment_count()
return '/'.join([
self.cache_url(),
filepath_to_uri(self._get_filename_for_size(photosize.name))])
def _get_size_filename(self, size):
photosize = PhotoSizeCache().sizes.get(size)
return smart_str(os.path.join(self.cache_path(),
self._get_filename_for_size(photosize.name)))
def increment_count(self):
self.view_count += 1
models.Model.save(self)
def __getattr__(self, name):
global size_method_map
if not size_method_map:
init_size_method_map()
di = size_method_map.get(name, None)
if di is not None:
result = partial(getattr(self, di['base_name']), di['size'])
setattr(self, name, result)
return result
else:
raise AttributeError
def size_exists(self, photosize):
func = getattr(self, "get_%s_filename" % photosize.name, None)
if func is not None:
if self.image.storage.exists(func()):
return True
return False
def resize_image(self, im, photosize):
cur_width, cur_height = im.size
new_width, new_height = photosize.size
if photosize.crop:
ratio = max(float(new_width) / cur_width, float(new_height) / cur_height)
x = (cur_width * ratio)
y = (cur_height * ratio)
xd = abs(new_width - x)
yd = abs(new_height - y)
x_diff = int(xd / 2)
y_diff = int(yd / 2)
if self.crop_from == 'top':
box = (int(x_diff), 0, int(x_diff + new_width), new_height)
elif self.crop_from == 'left':
box = (0, int(y_diff), new_width, int(y_diff + new_height))
elif self.crop_from == 'bottom':
# y - yd = new_height
box = (int(x_diff), int(yd), int(x_diff + new_width), int(y))
elif self.crop_from == 'right':
# x - xd = new_width
box = (int(xd), int(y_diff), int(x), int(y_diff + new_height))
else:
box = (int(x_diff), int(y_diff), int(x_diff + new_width), int(y_diff + new_height))
im = im.resize((int(x), int(y)), Image.ANTIALIAS).crop(box)
else:
if not new_width == 0 and not new_height == 0:
ratio = min(float(new_width) / cur_width,
float(new_height) / cur_height)
else:
if new_width == 0:
ratio = float(new_height) / cur_height
else:
ratio = float(new_width) / cur_width
new_dimensions = (int(round(cur_width * ratio)),
int(round(cur_height * ratio)))
if new_dimensions[0] > cur_width or \
new_dimensions[1] > cur_height:
if not photosize.upscale:
return im
im = im.resize(new_dimensions, Image.ANTIALIAS)
return im
def create_size(self, photosize, recreate=False):
if self.size_exists(photosize) and not recreate:
return
try:
im = Image.open(self.image.storage.open(self.image.name))
except OSError:
return
# Save the original format
im_format = im.format
# Apply effect if found
if self.effect is not None:
im = self.effect.pre_process(im)
elif photosize.effect is not None:
im = photosize.effect.pre_process(im)
# Rotate if found & necessary
if 'Image Orientation' in self.exif() and \
self.exif().get('Image Orientation').values[0] in IMAGE_EXIF_ORIENTATION_MAP:
im = im.transpose(
IMAGE_EXIF_ORIENTATION_MAP[self.EXIF().get('Image Orientation').values[0]])
# Resize/crop image
if (im.size != photosize.size and photosize.size != (0, 0)) or recreate:
im = self.resize_image(im, photosize)
# Apply effect if found
if self.effect is not None:
im = self.effect.post_process(im)
elif photosize.effect is not None:
im = photosize.effect.post_process(im)
# Save file
im_filename = getattr(self, "get_%s_filename" % photosize.name)()
try:
buffer = BytesIO()
if im_format != 'JPEG':
im.save(buffer, im_format)
else:
# Issue #182 - test fix from https://github.com/bashu/django-watermark/issues/31
if im.mode.endswith('A'):
im = im.convert(im.mode[:-1])
im.save(buffer, 'JPEG', quality=int(photosize.quality),
optimize=True)
buffer_contents = ContentFile(buffer.getvalue())
self.image.storage.save(im_filename, buffer_contents)
except OSError as e:
if self.image.storage.exists(im_filename):
self.image.storage.delete(im_filename)
raise e
def remove_size(self, photosize, remove_dirs=True):
if not self.size_exists(photosize):
return
filename = getattr(self, "get_%s_filename" % photosize.name)()
if self.image.storage.exists(filename):
self.image.storage.delete(filename)
def clear_cache(self):
cache = PhotoSizeCache()
for photosize in cache.sizes.values():
self.remove_size(photosize, False)
def pre_cache(self, recreate=False):
cache = PhotoSizeCache()
if recreate:
self.clear_cache()
for photosize in cache.sizes.values():
if photosize.pre_cache:
self.create_size(photosize, recreate)
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
self._old_image = self.image
def save(self, *args, **kwargs):
recreate = kwargs.pop('recreate', False)
image_has_changed = False
if self._get_pk_val() and (self._old_image != self.image):
image_has_changed = True
# If we have changed the image, we need to clear from the cache all instances of the old
# image; clear_cache() works on the current (new) image, and in turn calls several other methods.
# Changing them all to act on the old image was a lot of changes, so instead we temporarily swap old
# and new images.
new_image = self.image
self.image = self._old_image
self.clear_cache()
self.image = new_image # Back to the new image.
self._old_image.storage.delete(self._old_image.name) # Delete (old) base image.
if self.date_taken is None or image_has_changed:
# Attempt to get the date the photo was taken from the EXIF data.
try:
exif_date = self.exif(self.image.file).get('EXIF DateTimeOriginal', None)
if exif_date is not None:
d, t = exif_date.values.split()
year, month, day = d.split(':')
hour, minute, second = t.split(':')
self.date_taken = datetime(int(year), int(month), int(day),
int(hour), int(minute), int(second))
except Exception:
logger.error('Failed to read EXIF DateTimeOriginal', exc_info=True)
super().save(*args, **kwargs)
self.pre_cache(recreate)
def delete(self):
assert self._get_pk_val() is not None, \
"%s object can't be deleted because its %s attribute is set to None." % \
(self._meta.object_name, self._meta.pk.attname)
self.clear_cache()
# Files associated to a FileField have to be manually deleted:
# https://docs.djangoproject.com/en/dev/releases/1.3/#deleting-a-model-doesn-t-delete-associated-files
# http://haineault.com/blog/147/
# The data loss scenarios mentioned in the docs hopefully do not apply
# to Photologue!
super().delete()
self.image.storage.delete(self.image.name)
class Photo(ImageModel):
title = models.CharField(_('title'),
max_length=250,
unique=True)
slug = models.SlugField(_('slug'),
unique=True,
max_length=250,
help_text=_('A "slug" is a unique URL-friendly title for an object.'))
caption = models.TextField(_('caption'),
blank=True)
date_added = models.DateTimeField(_('date added'),
default=now)
is_public = models.BooleanField(_('is public'),
default=True,
help_text=_('Public photographs will be displayed in the default views.'))
class Meta:
ordering = ['-date_added']
get_latest_by = 'date_added'
verbose_name = _("photo")
verbose_name_plural = _("photos")
def __str__(self):
return self.title
def save(self, *args, **kwargs):
# If crop_from or effect property has been changed on existing image,
# update kwargs to force image recreation in parent class
current = Photo.objects.get(pk=self.pk) if self.pk else None
if current and (current.crop_from != self.crop_from or current.effect != self.effect):
kwargs.update(recreate=True)
if self.slug is None:
self.slug = slugify(self.title)
super().save(*args, **kwargs)
def get_absolute_url(self):
return reverse('photologue:pl-photo', args=[self.slug])
def public_galleries(self):
"""Return the public galleries to which this photo belongs."""
return self.galleries.filter(is_public=True)
def get_previous_in_gallery(self, gallery):
"""Find the neighbour of this photo in the supplied gallery.
We assume that the gallery and all its photos are on the same site.
"""
if not self.is_public:
raise ValueError('Cannot determine neighbours of a non-public photo.')
photos = gallery.photos.filter(is_public=True)
if self not in photos:
raise ValueError('Photo does not belong to gallery.')
previous = None
for photo in photos:
if photo == self:
return previous
previous = photo
def get_next_in_gallery(self, gallery):
"""Find the neighbour of this photo in the supplied gallery.
We assume that the gallery and all its photos are on the same site.
"""
if not self.is_public:
raise ValueError('Cannot determine neighbours of a non-public photo.')
photos = gallery.photos.filter(is_public=True)
if self not in photos:
raise ValueError('Photo does not belong to gallery.')
matched = False
for photo in photos:
if matched:
return photo
if photo == self:
matched = True
return None
class PhotoSize(models.Model):
"""About the Photosize name: it's used to create get_PHOTOSIZE_url() methods,
so the name has to follow the same restrictions as any Python method name,
e.g. no spaces or non-ascii characters."""
name = models.CharField(_('name'),
max_length=40,
unique=True,
help_text=_(
'Photo size name should contain only letters, numbers and underscores. Examples: '
'"thumbnail", "display", "small", "main_page_widget".'),
validators=[RegexValidator(regex='^[a-z0-9_]+$',
message='Use only plain lowercase letters (ASCII), numbers and '
'underscores.'
)]
)
width = models.PositiveIntegerField(_('width'),
default=0,
help_text=_(
'If width is set to "0" the image will be scaled to the supplied height.'))
height = models.PositiveIntegerField(_('height'),
default=0,
help_text=_(
'If height is set to "0" the image will be scaled to the supplied width'))
quality = models.PositiveIntegerField(_('quality'),
choices=JPEG_QUALITY_CHOICES,
default=70,
help_text=_('JPEG image quality.'))
upscale = models.BooleanField(_('upscale images?'),
default=False,
help_text=_('If selected the image will be scaled up if necessary to fit the '
'supplied dimensions. Cropped sizes will be upscaled regardless of this '
'setting.')
)
crop = models.BooleanField(_('crop to fit?'),
default=False,
help_text=_('If selected the image will be scaled and cropped to fit the supplied '
'dimensions.'))
pre_cache = models.BooleanField(_('pre-cache?'),
default=False,
help_text=_('If selected this photo size will be pre-cached as photos are added.'))
increment_count = models.BooleanField(_('increment view count?'),
default=False,
help_text=_('If selected the image\'s "view_count" will be incremented when '
'this photo size is displayed.'))
class Meta:
ordering = ['width', 'height']
verbose_name = _('photo size')
verbose_name_plural = _('photo sizes')
def __str__(self):
return self.name
def clear_cache(self):
for cls in ImageModel.__subclasses__():
for obj in cls.objects.all():
obj.remove_size(self)
if self.pre_cache:
obj.create_size(self)
PhotoSizeCache().reset()
def clean(self):
if self.crop is True:
if self.width == 0 or self.height == 0:
raise ValidationError(
_("Can only crop photos if both width and height dimensions are set."))
def save(self, *args, **kwargs):
super().save(*args, **kwargs)
PhotoSizeCache().reset()
self.clear_cache()
def delete(self):
assert self._get_pk_val() is not None, "%s object can't be deleted because its %s attribute is set to None." \
% (self._meta.object_name, self._meta.pk.attname)
self.clear_cache()
super().delete()
def _get_size(self):
return (self.width, self.height)
def _set_size(self, value):
self.width, self.height = value
size = property(_get_size, _set_size)
class PhotoSizeCache:
__state = {"sizes": {}}
def __init__(self):
self.__dict__ = self.__state
if not len(self.sizes):
sizes = PhotoSize.objects.all()
for size in sizes:
self.sizes[size.name] = size
def reset(self):
global size_method_map
size_method_map = {}
self.sizes = {}
def init_size_method_map():
global size_method_map
for size in PhotoSizeCache().sizes.keys():
size_method_map['get_%s_size' % size] = \
{'base_name': '_get_size_size', 'size': size}
size_method_map['get_%s_photosize' % size] = \
{'base_name': '_get_size_photosize', 'size': size}
size_method_map['get_%s_url' % size] = \
{'base_name': '_get_size_url', 'size': size}
size_method_map['get_%s_filename' % size] = \
{'base_name': '_get_size_filename', 'size': size}