takahe/core/files.py
2023-01-08 14:28:25 -07:00

88 lines
2.6 KiB
Python

import io
import blurhash
import httpx
from django.conf import settings
from django.core.files import File
from django.core.files.base import ContentFile
from PIL import Image, ImageOps
class ImageFile(File):
image: Image
def resize_image(
image: File,
*,
size: tuple[int, int],
cover=True,
keep_format=False,
) -> ImageFile:
"""
Resizes an image to fit insize the given size (cropping one dimension
to fit if needed)
"""
with Image.open(image) as img:
try:
# Take any orientation EXIF data, apply it, and strip the
# orientation data from the new image.
img = ImageOps.exif_transpose(img)
except Exception: # noqa
# exif_transpose can crash with different errors depending on
# the EXIF keys. Just ignore them all, better to have a rotated
# image than no image.
pass
if cover:
resized_image = ImageOps.fit(img, size, method=Image.Resampling.BILINEAR)
else:
resized_image = img.copy()
resized_image.thumbnail(size, resample=Image.Resampling.BILINEAR)
new_image_bytes = io.BytesIO()
if keep_format:
resized_image.save(new_image_bytes, format=img.format)
file = ImageFile(new_image_bytes)
else:
resized_image.save(new_image_bytes, format="webp", save_all=True)
file = ImageFile(new_image_bytes, name="image.webp")
file.image = resized_image
return file
def blurhash_image(file) -> str:
"""
Returns the blurhash for an image
"""
return blurhash.encode(file, 4, 4)
async def get_remote_file(
url: str,
*,
timeout: float = settings.SETUP.REMOTE_TIMEOUT,
max_size: int | None = None,
) -> tuple[File | None, str | None]:
"""
Download a URL and return the File and content-type.
"""
headers = {
"User-Agent": settings.TAKAHE_USER_AGENT,
}
async with httpx.AsyncClient(headers=headers) as client:
async with client.stream("GET", url, timeout=timeout) as stream:
allow_download = max_size is None
if max_size:
try:
content_length = int(stream.headers["content-length"])
allow_download = content_length <= max_size
except (KeyError, TypeError):
pass
if allow_download:
file = ContentFile(await stream.aread(), name=url)
return file, stream.headers.get(
"content-type", "application/octet-stream"
)
return None, None