Handling large file uploads with Flask

Question

What would be the best way to handle very large file uploads (1 GB +) with Flask?

My application essentially takes multiple files assigns them one unique file number

Answer 1

Use copy_current_request_context,it will duplicate the context request.so you can use thread or anything else to make your task running background.

maybe an example will make it be clear.i have test it by a 3.37G file-debian-9.5.0-amd64-DVD-1.iso.

# coding:utf-8

from flask import Flask,render_template,request,redirect,url_for
from werkzeug.utils import secure_filename
import os
from time import sleep
from flask import copy_current_request_context
import threading
import datetime
app = Flask(__name__)
@app.route('/upload', methods=['POST','GET'])
def upload():
    @copy_current_request_context
    def save_file(closeAfterWrite):
        print(datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S') + " i am doing")
        f = request.files['file']
        basepath = os.path.dirname(__file__) 
        upload_path = os.path.join(basepath, '',secure_filename(f.filename)) 
        f.save(upload_path)
        closeAfterWrite()
        print(datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S') + " write done")
    def passExit():
        pass
    if request.method == 'POST':
        f= request.files['file']
        normalExit = f.stream.close
        f.stream.close = passExit
        t = threading.Thread(target=save_file,args=(normalExit,))
        t.start()
        return redirect(url_for('upload'))
    return render_template('upload.html')

if __name__ == '__main__':
    app.run(debug=True)

this is tempalte,it should be templates\upload.html

    
    


    
example