# Code lifted from this simple tutorial:
# https://flask.palletsprojects.com/en/2.3.x/patterns/fileuploads/
import os
from flask import Flask, flash, request, redirect, url_for, send_from_directory
from flask import get_flashed_messages
from werkzeug.utils import secure_filename
import secrets
# Location of uploaded files, and legal upload extensions.
#UPLOAD_FOLDER = "/tmp/uploads"
UPLOAD_FOLDER = "/home/bennet/courses/cs445/flask/uploads"
ALLOWED_EXTENSIONS = {'txt', 'pdf', 'png', 'jpg', 'jpeg', 'gif'}
# Create app and configure that upload location
app = Flask(__name__)
app.config['UPLOAD_FOLDER'] = UPLOAD_FOLDER
app.secret_key = secrets.token_bytes()
# Helper to check the file name extension against the permitted list.
def allowed_file(filename):
return '.' in filename and \
filename.rsplit('.', 1)[1].lower() in ALLOWED_EXTENSIONS
# Very simple upload view and processor.
@app.route('/', methods=['GET', 'POST'])
def upload_file():
# See if we're handling a POST (file transmission in this case).
if request.method == 'POST':
# check if the post request has a file entry called myfile
if 'myfile' not in request.files:
flash('No file part')
return redirect(request.url)
# Get the file from the request. Flask (or wsgi) saved the data
# somewhere. This returns a descriptive object
file = request.files['myfile']
# No file was actually submitted through the form.
if file.filename == '':
flash('No selected file')
return redirect(request.url)
# File was submitted, and name had an legal ending.
if file and allowed_file(file.filename):
# Get the file name, make it saft to use, and save the file
# in its final location using the file object.
filename = secure_filename(file.filename)
file.save(os.path.join(app.config['UPLOAD_FOLDER'], filename))
return redirect(url_for('download_file', name=filename))
else:
flash('Forbidden extension')
err = ''
if len(get_flashed_messages()) > 0:
err=""+"
".join(get_flashed_messages())+"
";
return '''
Upload new File
Upload new File
%s
''' % err
# This handles the "upload" link, which simply directs the browser
# to a given file.
@app.route('/uploads/')
def download_file(name):
return send_from_directory(app.config["UPLOAD_FOLDER"], name)