Fork by: Joe Schroecker on 2015/07/17 Reason: Almost complete rewrite to be more modular. Now supports storing and fetching Thumbnails in Google Cloud Storage. ^

A simple extension to create a thumbs for the Flask

Install with pip:

Run pip install git+https://github.com/SilentSokolov/flask-thumbnails.git

Add Thumbnail to your extension file:

from flask.ext.thumbnails import Thumbnail

app = Flask(__name__)

thumb = Thumbnail(app)

Add MEDIA_FOLDER and MEDIA_URL in your settings:

app.config['MEDIA_FOLDER'] = '/home/www/media'
app.config['MEDIA_URL'] = '/media/'

Use in Jinja2 template:

<img src="{{ 'image.jpg'|thumbnail('200x200') }}" alt="" />
<img src="{{ 'image.jpg'|thumbnail('200x200', crop='fit', quality=100) }}" alt="" />

crop='fit' returns a sized and cropped version of the image, cropped to the requested aspect ratio and size, read more.

quality=XX changes the quality of the output JPEG thumbnail, default 85.

In production, you need to add media directory in you web server.

To service the uploaded files need a helper function, where /media/ your settings app.config['MEDIA_URL']:

from flask import send_from_directory

@app.route('/media/<regex("([\w\d_/-]+)?.(?:jpe?g|gif|png)"):filename>')
def media_file(filename):
    return send_from_directory(app.config['MEDIA_THUMBNAIL_FOLDER'], filename)

If you want to store the thumbnail in a folder other than the MEDIA_FOLDER, you need to set it manually:

app.config['MEDIA_THUMBNAIL_FOLDER'] = '/home/www/media/cache'
app.config['MEDIA_THUMBNAIL_URL'] = '/media/cache/'