testapp.py

# mitsuhiko/flask#637

from flask import send_file, Flask, request
import datetime

app = Flask(__name__)

@app.route('/image/<file_id>')
def images(file_id):
    f = open('lel.jpg')  # some jpeg file in the same dir
    rv = send_file(f,
                   mimetype='image/jpg',
                   # as_attachment=True,
                   attachment_filename='lel.jpg',
                   add_etags=False,
                   conditional=True
                   )
    rv.last_modified = datetime.datetime.strptime('2012-11-24 08:51:27', '%Y-%m-%d %H:%M:%S')
    app.logger.debug(rv.last_modified)    # 2012-11-24 08:51:27
    app.logger.debug(request.if_modified_since)    # 2012-11-24 08:51:27
    #app.logger.debug(rv.last_modified<=request.if_modified_since)    # True
    return rv

app.run(debug=True)