comparison core/images/upload.py @ 971:4f265f61874b

Hotlink image form is functioning. The user can now submit a URL via a form and the URL will be downloaded and uploaded to a S3 bucket if it is an image. Tests to follow.
author Brian Neal <bgneal@gmail.com>
date Tue, 22 Sep 2015 20:23:50 -0500
parents core/image_uploader.py@51a2051588f5
children 7fc6c42b2f5b
comparison
equal deleted inserted replaced
970:bd594bcba5eb 971:4f265f61874b
1 """This module contains a function to upload an image file to a S3Bucket.
2
3 The image can be resized and a thumbnail can be generated and uploaded as well.
4
5 """
6 from base64 import b64encode
7 import logging
8 from io import BytesIO
9 import os.path
10 import uuid
11
12 from PIL import Image
13
14 from .utils import orient_image
15
16
17 logger = logging.getLogger(__name__)
18
19
20 def make_key():
21 """Generate a random key suitable for a filename"""
22 return b64encode(uuid.uuid4().bytes, '-_').rstrip('=')
23
24
25 def upload(filename, bucket, metadata=None, new_size=None, thumb_size=None):
26 """Upload an image file to a given S3Bucket.
27
28 The image can optionally be resized and a thumbnail can be generated and
29 uploaded as well.
30
31 Parameters:
32 filename - The path to the file to process. The filename should have an
33 extension, and this is used for the uploaded image & thumbnail
34 names.
35 bucket - A core.s3.S3Bucket instance to upload to.
36 metadata - If not None, must be a dictionary of metadata to apply to the
37 uploaded file and thumbnail.
38 new_size - If not None, the image will be resized to the dimensions
39 specified by new_size, which must be a (width, height) tuple.
40 thumb_size - If not None, a thumbnail image will be created with the
41 dimensions specified by thumb_size, which must be a (width,
42 height) tuple. The thumbnail will use the same metadata, if
43 present, as the image. The thumbnail filename will be the
44 same basename as the image with a 't' appended. The
45 extension will be the same as the original image.
46
47 A tuple is returned: (image_url, thumb_url) where thumb_url will be None if
48 a thumbnail was not requested.
49 """
50
51 logger.info('Processing image file: %s', filename)
52
53 unique_key = make_key()
54 ext = os.path.splitext(filename)[1]
55
56 # Re-orient if necessary
57 image = Image.open(filename)
58 changed, image = orient_image(image)
59 if changed:
60 image.save(filename)
61
62 # Resize image if necessary
63 if new_size:
64 image = Image.open(filename)
65 if image.size > new_size:
66 logger.debug('Resizing from {} to {}'.format(image.size, new_size))
67 image.thumbnail(new_size, Image.ANTIALIAS)
68 image.save(filename)
69
70 # Create thumbnail if necessary
71 thumb = None
72 if thumb_size:
73 logger.debug('Creating thumbnail {}'.format(thumb_size))
74 image = Image.open(filename)
75 image.thumbnail(thumb_size, Image.ANTIALIAS)
76 thumb = BytesIO()
77 image.save(thumb, format=image.format)
78
79 # Upload images to S3
80 file_key = unique_key + ext
81 logging.debug('Uploading image')
82 image_url = bucket.upload_from_filename(file_key, filename, metadata)
83
84 thumb_url = None
85 if thumb:
86 logging.debug('Uploading thumbnail')
87 thumb_key = '{}t{}'.format(unique_key, ext)
88 thumb_url = bucket.upload_from_string(thumb_key,
89 thumb.getvalue(),
90 metadata)
91
92 logger.info('Completed processing image file: %s', filename)
93
94 return (image_url, thumb_url)