https://github.com/mitsuhiko/flask/issues/1169

__init__.py

import flask

app = flask.Flask('testapp')

@app.route('/dir')
def from_dir():
    return flask.send_from_directory('data', 'file.txt')

@app.route('/file')
def from_file():
    return flask.send_file('data/file.txt')

fileindex.txt

.
    testapp
        data
            file.txt
        __init__.py
    runserver.py

runserver.py

from testapp import app

app.run()

Hey, I check the example, and I am pretty sure the http://127.0.0.1/dir will occur a 404 not found error in my computer. here is the error code: "if not os.path.isfile(filename):" in send_from_directory.

mac osx, Python 2.7.5 :: Anaconda 1.8.0 (x86_64).