Sm0ke

Posted on Jan 14, 2021 • Updated on Feb 26, 2021

Flask Tutorial - The Interactive way, Ask Me Anything for three hours

#flask #webdev #python

Hello Coders,

My (nick)name is Sm0ke and I'm using Flask for more than 5 years to code almost anything: simple one-page projects, API's and eCommerce-based platforms. The deployments were made starting with Apache, Nginx, Gunicorn, and uWSGI .. etc. Regarding this Flask Tutorial, the content will be provided based on your questions, starting with just a few links.

Thank you! Content provided by AppSeed - App Generator.

I'll be around here for 3hours - feel free to ask me anything. During this timeframe I'll do my best to provide quality answers based on my practical knowledge - Some Flask-related links:

Flask - the official website
Flask Docs
Flask Tutorial - (Github) Content provided by experienced developers.
Flask - A list of useful “HOW TO’s”
Flask Cheat Sheet - And FREE samples

Suggested Topics:

Deployment on CentOS, Ubuntu using Apache/Nginx
Start app using Gunicorn, uWSGI
What is WSGI
How to structure a project
ORM - how to use it and manage DB information with ease
Migrations - using Flask Migration
Flask Admin - using roles in a Flask application
Protecting routes in Flask
Session-based authentication via Flask-Login
Using the Flask CLI
Create custom (CLI) commands using Click
Create tables dynamically - at first request

Oldest comments (20)

ui-themes • Jan 14 '21

Cool idea. What are blueprints? When is recommended to use BP.
Ty!

Sm0ke • Jan 14 '21 • Edited

Blueprints are basically modules, similar to apps in Django.
Once a project is getting bigger, the files tend to become huge and not so easy to handle.
Using Blueprints, we can split the features using a modular structure. The official documentation is nicely written. Take a look and let me know if your thoughts.

Flask Blueprints - docs

WebsiteMarket • Jan 14 '21

Hello Sm0ke and Thanks for your time!
Can I use Flask embedded server for a production deploy?
I'm a beginner and configuring Apache/Nginx is not an easy job for me.

Sm0ke • Jan 14 '21

Hello,
Flask provides the embedded server mostly for development purposes. As mentioned on the official docs regarding the deployment, "Flask’s built-in server is not suitable for production".

Besides this warning, I see two major problems:

you cannot enforce SSL and the connections will be served via HTTP
The Flask core is not build to handle concurrency

Even is not a simple task to configure a server, once you learn to do it, your application will be faster and secure.

Jonyk56 • Jan 14 '21

is flask able to have endpoints closed/opened on command?

Sm0ke • Jan 14 '21 • Edited

Can you elaborate, please?
if your Q address something like a dynamic routing based on the input, I think you can manage this in a controller and bypass the classic Flask routing:

@app.route('/whatever.html', methods=['GET', 'POST'])
def whatever():
    ... Routing hacks HERE

ArturoDRR • Jan 14 '21

Hello what is the simplest and cheapest way to deploy a flask site?
I am beginner and recently I had an opportunity to make a landing page for an architecture agency, and I saw that flask is very easy to use, but I am seeing that some shared hostings doesn't support python. What you suggest me to do, or do I have to change stack. Thank you.

Sm0ke • Jan 14 '21

Heroku has a free tier and is super easy to set up.
Another option is to buy a 5$ Droplet on DigitalOcean and use it for many projects.
Also, using a raw droplet, and make your own configuration in Apache/Nginx you will learn a lot.

Alin Climente • Jan 14 '21

Do you have/Can you recommend a repo for a docker(-compose) setup dev+prod ?

Sm0ke • Jan 14 '21

Hello,

I've built some starters in Flask, already Dockerized. For sure the repos are not the best on the market but can be used to have a good start:

Both are tested and released under MIT License.

abuakram • Jan 14 '21

Hi... thanks for your effort...
I was thinking of creating a folder in my flask project which is synchronized with my database... So that to speed up the speed...
Is this possible???

Sm0ke • Jan 15 '21

Hello,
Your pattern is quite original. Can you elaborate, please?
If you want to speed up things, not only in Flask, you have at least two options:

Tune-up the database - define indexes on tables, using stored procedures, views
Use Redis to cache in memory critical information

If you have the time, please access this guide related to Flask:

How to increase Flask performance

abuakram • Jan 15 '21

Your link is so rich of important information... I couldn't stop reading... Are you by any chance Smirnov???

Concerning speed, since querying a database takes time... I thought of creating a folder that does a query to the db only after each update for synchronization (mirror of db) ... So it should be acting similar to flatpages.

Sm0ke • Jan 15 '21

Smirnov??? .. who's this guy?

Between flatpages and DB pretty sure DB is faster and easier to locate the information.
On top of this, Redis is usually a solution to by-pass the DB queries.

Cheers!

abuakram • Jan 15 '21

smirnov-am.github.io/flask-perf/

this smirnov

Sm0ke • Jan 15 '21

Nope :)

abuakram • Jan 15 '21

Hi, a second question please...
Concerning security, does one have to depend on extensions to gain full security, or is Flask enough... I am asking this question because a developer can stop maintaining his extension and apps relying on it gets buggy.

Sm0ke • Jan 16 '21 • Edited

Secure a web app is not an easy job but Flask helps a lot regarding this sensitive topic.
When your application uses a public module it might be a good idea to check a few relevant metrics: