def __init__(self, min_length: int=None, max_length: int=None, content_type: str=None, content_length: int=None,
extension: str=None, original_filename: str=None, header_buffer_size=1024,
reproducible: bool=False, **kwargs):
self.min_length = min_length
self.max_length = max_length
self.header_buffer_size = header_buffer_size
self.content_length = content_length
self.original_filename = original_filename
self._source_pos = 0
for k, v in kwargs.items():
setattr(self, k, v)
if content_type:
self.content_type = content_type
elif original_filename:
self.content_type = guess_type(original_filename)
elif extension:
self.content_type = guess_type('a' + extension)
if extension:
self.extension = extension
elif self.original_filename:
self.extension = splitext(self.original_filename)[1]
elif self.content_type:
self.extension = guess_extension(self.content_type)
self.reproducible = reproducible
def process(self, descriptor: StreamDescriptor, context: dict):
# Ensuring the wand package is installed.
ensure_wand()
# noinspection PyPackageRequirements
from wand.image import Image as WandImage
# Copy the original info
# generating thumbnail and storing in buffer
# noinspection PyTypeChecker
img = WandImage(file=descriptor)
if self.crop is None and (
self.format is None or img.format == self.format) and (
(self.width is None or img.width == self.width) and
(self.height is None or img.height == self.height)):
img.close()
descriptor.prepare_to_read(backend='memory')
return
if 'length' in context:
del context['length']
# opening the original file
output_buffer = io.BytesIO()
with img:
# Changing format if required.
if self.format and img.format != self.format:
img.format = self.format
# Changing dimension if required.
if self.width or self.height:
width, height, _ = validate_width_height_ratio(
self.width, self.height, None)
img.resize(
width(img.size) if callable(width) else width,
height(img.size) if callable(height) else height)
# Cropping
if self.crop:
img.crop(
**{
key: int(
int(value[:-1]) / 100 *
(img.width if key in ('width', 'left',
'right') else img.height)
) if key in ('left', 'top', 'right', 'bottom', 'width',
'height') and '%' in value else value
for key, value in self.crop.items()
})
img.save(file=output_buffer)
context.update(content_type=img.mimetype,
width=img.width,
height=img.height,
extension=guess_extension(img.mimetype))
output_buffer.seek(0)
descriptor.replace(output_buffer, position=0, **context)