def to_python(self, data):
"""
Checks that the file-upload field data contains a valid source file
(GIF, JPG, PNG, WEBM, MP4, etc) using imageio plugins.
"""
f = super(ThumbnailerExtField, self).to_python(data)
if f is None:
return None
# Check filesize limit
# Nginx client_max_body_size is 5MB
if f.size > 5 * 1024 * 1024:
raise ValidationError(self.error_messages['max_size'],
code='max_size')
from pathlib import PurePath
# Check for file extension
ext = PurePath(f.name).suffix
if ext == '':
raise ValidationError(self.error_messages['invalid_extension'],
code='invalid_extension')
# Get temporary file path or raw bytes
if hasattr(data, 'temporary_file_path'):
file = data.temporary_file_path()
else:
if hasattr(data, 'read'):
file = BytesIO(data.read())
else:
file = BytesIO(data['content'])
from PIL import Image
from imageio import get_reader
try:
# Firstly try and recognise BytesIO
file = get_reader(file)
# Send data to PIL
f.image = Image.fromarray(file.get_data(0))
# Close the reader
force_close_reader(file)
except ValueError:
# Create a local file
with NamedTemporaryFile(suffix=ext) as n:
for chunk in data.chunks():
n.write(chunk)
try:
# Try and read from temporary file
file = get_reader(n.name)
# Send data to PIL
f.image = Image.fromarray(file.get_data(0))
except OSError:
# FFmpeg cannot read video meta
# May be out of memory for a new reader (bug #48)
params = { 'file': f.name }
raise ValidationError(self.error_messages['corrupt_file'],
code='corrupt_file',
params=params)
except Exception:
# imageio doesn't recognize it as an image.
params = { 'types': self.types }
raise ValidationError(self.error_messages['invalid_file'],
code='invalid_file',
params=params)
finally:
# Close Named Tempoary File
n.close()
# Make sure any open reader is closed
force_close_reader(file)
# Check if this format is enabled
# See ``imageboard.settings`` for more information
if file.format.name in formats.keys():
# MIME type is not supported with imageio
# Thus if the content type is not detected, it will remain as None
f.content_type = Image.MIME.get(f.image.format)
if hasattr(f, 'seek') and callable(f.seek):
f.seek(0)
return f
else:
params = { 'types': self.types }
raise ValidationError(self.error_messages['unsupported'],
code='unsupported',
params=params)
