Python Flask Authentication Tutorial - Learn Flask Login

Hey guys! Welcome back! In this video, I show you how to build a login authentication system using Flask and Python. We'll be using Flask-Login to build it.
If you don't know about Flask or if this is your first time using it, Flask is a Python web framework that is used to create web applications. Flask has a built-in login system that can be used to authenticate users. The login system in Flask is very simple and only requires a user to enter their username and password.
Mac Command - pip3 install flask flask_sqlalchemy flask_login flask_bcrypt flask_wtf wtforms email_validator
Windows Command - pip install flask flask_sqlalchemy flask_login flask_bcrypt flask_wtf wtforms email_validator
Code: github.com/arp...
My Website - arpanneupane.com
My GitHub: github.com/arp...
Official Flask-Login Docs - flask-login.re...
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#Python // #Flask // #LearnToCode

[@ArpanNeupaneProductions]

For people wondering where the code is in this video, you can find it here: github.com/arpanneupane19/Python-Flask-Authentication-Tutorial

[@iancorrea3151]

Can i request a tutorial about React and Flask Authentication? Thank you.

[@k.c.9019]

That's not the same code. Code in github doesn't have at least check_password_hash part.

[@ArpanNeupaneProductions]

@@k.c.9019 Thank you for reminding me. I hadn’t added a repo for this app when the video was made and saw many people requesting it so I decided to make one this month. Thanks for reminding me though.

[@k.c.9019]

@@ArpanNeupaneProductions Thank you for your work :)

[@Jack__2]

​@@iancorrea3151 I am also making react + flask app have you make login and register page

[@HassanRaza-cb3mz]

I don't usually comment on videos, but WOW. This is the most simplest and most focused tutorial for this particular subject. You are doing great job man! loved the video.

[@davidk7212]

Straight to the point with no fluff, yet thorough and with every detail explained succinctly. And no cringey attempts at comedy. This is exactly what the world needs more of.

[@SanSha2100]

What people are taking hours and still not able to illustrate, your focused approach teaches it minimum time with maximum impact. Kudos to you and very well done.

[@philippkeller5882]

Such a great tutorial. I like that you focussed on the bare minimum, no styling, no fancy databases, no long explanations. That got me going with login and forms in Flask

[@wdblackout]

right! tutorial nowadays just focused on the number of minutes for the views.

[@ArpanNeupaneProductions]

Haha I appreciate it!

[@Vangsguard]

@@wdblackout You are aware that you can just... skip those parts of the video right? Also if you don't like long explanations you might want to find a different career. Understand why you do what you do is the most important in this field. Doing it is one thing, understanding why is what's hard. If not everyone could be a programmer with ChatGPT.

[@wdblackout]

@@Vangsguard necroposting. this is two years already and too late for a debate. you just have a kitkat, take a break alright?

[@h_0412]

One of the best tutorial I've ever seen. I really appreciate that you chose to explain your code instead of blasting some random music like some other tutorials nowadays. Thank you!

[@alwinjames4777]

showing this error at 14:41 >>> from app import db Traceback (most recent call last): File "", line 1, in File "C:\Users\User\Desktop\flask-auth\app.py", line 5, in db = SQLAlchemy(app) File "C:\Users\User\AppData\Local\Programs\Python\Python39\lib\site-packages\flask_sqlalchemy\extension.py", line 219, in __init__ self.init_app(app) File "C:\Users\User\AppData\Local\Programs\Python\Python39\lib\site-packages\flask_sqlalchemy\extension.py", line 301, in init_app raise RuntimeError( RuntimeError: Either 'SQLALCHEMY_DATABASE_URI' or 'SQLALCHEMY_BINDS' must be set. can you please help me

[@person....4169]

lol, I got the same issue did you find a solution?

[@PranavMalleboyina]

@@person....4169 The solution would be to create the db object after you set the URI and the secret key values. I tried this and it worked fine.

[@21Gannu]

you made this so simple. kudos… I suggest making whole series on flask it will benefit many students…

[@ArpanNeupaneProductions]

Thank you!!

[@Drinkyoghurt]

I'm having issues with it setting up the DB file. for some reason it won't take. If I add a create_tables function it creates one in instance, but then doesn't seem to access it. Every time I submit my form it just reloads instead of taking the data I submitted

[@steamhackman]

Just to echo most other commenters, great tutorial and very concise. Got my app up and running. Thank you muchly.

[@ArpanNeupaneProductions]

Glad to have been able to help

[@kevinrodriguez-zk5kq]

Hi! I'm having the message error for Either SQLALCHEMY_DATABASE_URI nor SQLALCHEMY_BINDS is set after I try to import db. Is this something outside of this tutorial? I am unsure as to why it continues to pop up.

[@moazali4757]

You might want to move the creation of the db object after configuring the database URI. It will solve this problem. Here's how you can modify your code: app = Flask(__name__) app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///database.db' # Move the configuration here app.config['SECRET_KEY'] = 'thisisasecretkey' db = SQLAlchemy(app) # Initialize the db object after configuring the app bcrypt = Bcrypt(app) Copy this code, and replace with previous lines of code.

[@wimvangeyt3866]

put the db = SQLAlchemy(app) after the config statements

[@Bob-kq6gt]

dont you need sessions to keep being logged in? Also my I mirror what you write and my database does not work.

[@EpicNerdify]

Hi sir, at 14:00 when i try to do import , i get this error ModuleNotFoundError: No module named 'flask', does anyone know of a fix for this? i have installed every necessary flask pip install modules

[@NasserAlshareefKSA]

me too

[@RansbyJohan]

When I run your code i get this error, can you help? Traceback (most recent call last): File "/home/johan/Dokumenter/login/app.py", line 10, in db = SQLAlchemy(app) File "/usr/local/lib/python3.9/dist-packages/flask_sqlalchemy/extension.py", line 219, in __init__ self.init_app(app) File "/usr/local/lib/python3.9/dist-packages/flask_sqlalchemy/extension.py", line 307, in init_app raise RuntimeError( RuntimeError: Either 'SQLALCHEMY_DATABASE_URI' or 'SQLALCHEMY_BINDS' must be set. B

[@tinymicronano]

me too

[@geoffreyfouvry6094]

On a scale of 10, you got 11.5... Just one thing: Don't forget the .decode('utf8') in the line............ hashed_password = bcrypt.generate_password_hash(form.password.data).decode('utf8')

[@mithunchandrasaha403]

Very Nice Explanation,Sir.Needs More Tutorial from you.

[@black_ninja1858]

I have a problem on 14:02 when typing from app import db I got: RuntimeError: Either 'SQLALCHEMY_DATABASE_URI' or 'SQLALCHEMY_BINDS' must be set. I' ve done everuthing same (working on Ubuntu) .I spent some time looking for solution, but couldn't find :((. Can anyone help please??

[@paritoshraikar4026]

try database and secret key commands before db=SQLAlchemy(app) and bcrypt=Bcrypt(app)..worked for me

[@leonardoloayza]

@@paritoshraikar4026 It worked!!!

[@lmoreno2103]

@@paritoshraikar4026 worked for me, had same issue. thanks!

[@rahulsumbly7310]

Hey, very nice and useful video 👍. Just one suggestion, make playlists on your channel for videos on same topic it will be easier for users to navigate videos on your channel

[@johannahigbea4521]

Great video, love that you go step by step and explain why you are adding the code. I know you are using a MAC, but wanted to ask if you tested this full tutorial in a Windows system. It seems that many users are having issues with the DB part of the tutorial and think it might be good for you to provide more insight and answers on the issues that may occur in a Windows environment. When I run 'from app import db', it creates a folder called instance, therefore, when I run db.create_all() I get an error, because there is no database.db in the instance folder.. Can you please try this exact tutorial in Windows and update the video to include the differences? Thank you!

[@indranil]

Great video!!.. Slightly off topic, which vscode theme have u used?

[@Andreasstanca95]

Amazing content but I get stuck at some point. when I want to db.create_all() in my terminal, I get the following error: RuntimeError: Working outside of application context. Any ideas how to solve this?

[@end_player4032]

i have the same problem

[@RenanL.S.]

When I put the key and SQLAlchemy part I get this: RuntimeError: Either 'SQLALCHEMY_DATABASE_URI' or 'SQLALCHEMY_BINDS' must be set My webpage stop working.

[@alwinjames4777]

SAME HERE .DID YOU GET THE SOLUTION OR NOT

[@rarisenpai]

I am now a new subscriber you make great content and am going to watch every video I can from now on😄

[@ArpanNeupaneProductions]

Welcome aboard!

[@Cookie_Hub]

I get this Error: pls help Either 'SQLALCHEMY_DATABASE_URI' or 'SQLALCHEMY_BINDS' must be set. File "/home/miuka/Python/FlaskTest2/app.py", line 10, in db = SQLAlchemy(app)

[@selendivanloglu1932]

Hi Arpan, thanks for the tutorial, very simple and effective. I'm on minute 13.56 right now, and my terminal is giving me a runtime error though I don't know why. I followed the code you wrote exactly, but this "RuntimeError: Either 'SQLALCHEMY_DATABASE_URI' or 'SQLALCHEMY_BINDS' must be set." is showing up on my terminal. Do you know how I can solve this? Thanks so much

[@jeanlecigne4379]

pip3 uninstall flask_sqlalchemy and pip3 install flask-sqlalchemy==2.5.1because big changes with flask-sqlalchemy==3.0 sqlite db in memory not set as default in this version

[@omar_benaidy]

@@jeanlecigne4379 thank you so much you're a life saver

[@kylekelly7232]

@@jeanlecigne4379 just curious what you would need to do to use v3.0?

[@josikie]

@@kylekelly7232 Hi Kyle! We can initialize the db first. Only after adding configurations, do we use db.init_app(app) to bind the db to the app.

[@willisvensson]

lifesaver comment, appriciated. Thank you!!!

[@progger1050]

I have a questions If I login I want to create a session but how to get the user name in the session because it is coming from the form

[@ArpanNeupaneProductions]

If you want to get the user’s name from the session, you can just do current_user.username.

[@progger1050]

What is {{hidden_tag}} error is say 1 positional argument required self

[@ArpanNeupaneProductions]

Can you share your code?

[@ChanderMohan-lj9dy]

Hi, I'm getting this error "sqlalchemy.exc.OperationalError: (sqlite3.OperationalError) no such table: user" when I try to register any name and am not able to solve the issue. Any assistance is greatly appreciated.

[@dope166]

The validate_username function in register form, you haven’t called it anywhere in the app, how does it work? Is it called automatically?

[@ammarbinmadi7175]

at 14:27 my Sqlite database file didn't contain any tables so i followed the following format #Unix/Mac (note the four leading slashes) sqlite:////absolute/path/to/foo.db #Windows (note 3 leading forward slashes and backslash escapes) sqlite:///C:\\absolute\\path\\to\\foo.db #Windows (alternative using raw string) r'sqlite:///C:\absolute\path\to\foo.db' in my Sqlite file link at line 7

[@atakankaraman4005]

hello, i got an error message when i import library as a "from flask_wtf import FlaskForm" i received an error. ImportError: cannot import name 'url_encode' from 'werkzeug'. i've installed all library from requirements.txt with same version my python version is 3.10. pycharm version is 2022.3.1. what is your python version could you please help me

[@slc388]

when i type from app import db it shows error like name 'db' is not defined why it shows like that please reply me sir

[@ArpanNeupaneProductions]

Can you share the code?

[@BaoNguyendarkmatter820]

At 13:18, I had to put line 7 and 8 (appp.config) before db=SQLAl to resolve a runtime error.

[@danielfaran5783]

thanks for the info

[@Quaght]

Say I have 5 web pages but only one of them requires a login. Do I add @login_required only to the route to that page?

[@ArpanNeupaneProductions]

Yes

[@arunkumarvaradala7139]

Really helpful, Explained with very clear, Thank you so much. keep doing Many more on Flask and Machine Learning too.

[@ArpanNeupaneProductions]

of course!

[@gregkrakow872]

I like the simplicity of your approach. The app contains just what is needed and it is explained all in less than 30 minutes. Is the code available for this project?

[@ArpanNeupaneProductions]

Thank you so much! The code is currently not available yet, I will make a GitHub repository for it.

[@OmPathare-h1o]

Really liked the video. This is my first flask project. Understood many basic concepts. Thank you. The code is working.

[@Sophistry0001]

Can't get past 14:00. Keep getting an error that I have no clue how to solve

[@ritusikpusik]

When I'm trying to import db from app I'm getting ImportError: cannot import name 'db' from 'app'. Why is that so?

[@aestedits4150]

Hi thanks for this great tutorial. I am having a problem, "database.db" is not working for me, I have installed SQL all extensions but the problem is same still. Could you please help.

[@baldoggie]

it is not working for me either

[@MyselfGagan]

Hi , I Am "ValueError: Invalid salt" while validating the login inputs, I have tried everything from google but not able to resolve it, please help me out in this

[@khurshidbekkk2647]

Your explanation is so plain and understandable. Thank you very much. You have just earned another follower!

[@jspencer89yt]

Anyone viewing this in 2023 this process has changed some. So expect some errors follow the documentation for latest updates.

[@riteshkolate05]

Where is documentation????

[@valeeswarank]

Nutshell explanation and simple and super mini project.

[@andremiruzzi8968]

Been following the tutorial up to the point where you run the .tables command , but for me it is returning nothing. i had to do the create_all() this way in order for it to work: >>> from app import app, db >>> app.app_context().push() >>> db.create_all() >>> exit() but when i check with the .tables i find nothing there

[@KS-ic4wv]

facing the same problem

[@andremiruzzi8968]

@@KS-ic4wv it seems that the version for flask alchemy changed a bit. I found a fix here however: kzbin.info/www/bejne/hKqUmGCNoJqhr68&ab_channel=PeterSchneider

[@1nicetyp431]

Thanks you saved my evening, simple but wonderful

[@aleksahadzic9302]

For people who already know how to set up the flask app, you can start watching from 9:40

[@peya02]

What steps should I do to deploy the app on a hosting? I'm trying and I get internal server error. You don't like something about the login part.

[@TomTwyman]

Wow! Great video! you just saved me a TON of time - new to Flask, and I was busy trying to piece together everything I needed for a simple authentication system, and you nailed it in one! Thanks a ton! I do have a question about some of the items in your requirements.txt - you have some items in there that aren't explicitly called out in the video - cffi, asgiref, dnspython, etc. Can you expand on why you included them?

[@adedayoadewale2509]

after create_all user is not showing up after .tables

[@christiannahas2142]

is it possible to add in the def register(): function a connection, cursor, and cursor.execute(INSERT...) to save the data entered in the register into a sqlite3 data base that is already created? Because when i tried that the data was not saving in the database.

[@arjunpukale3310]

very simple and up to the point ❤

[@milesthomas3317]

Really helpful, thanks so much.

[@andyguan3553]

i was wondering why i cant from app import db? it only says that ImportError: cannot import name 'db' from 'app'

[@aniketkadukar7772]

Man, You're awesome. Thanks!!

[@ArpanNeupaneProductions]

You’re welcome!

[@RocketLR]

is it just me or did u forget to show the part where u filled in the forms action attribute? I cant find it where you put that info in..

[@susanadesoji671]

This is a great tutorial, very helpful

[@ArpanNeupaneProductions]

Thanks!

[@Oc3anWav3s]

Just found this video and I loved how well you described everything! You earned a subscriber. Could you possibly make a video trailing off this - when a user logs in with their username, it will display the dashboard based on their specific details?

[@ArpanNeupaneProductions]

Thank you for the compliment! When they log in, you can do something like this in the HTML file: {{ current_user.username }}, etc.

[@ArpanNeupaneProductions]

You can basically access the current_user object in Flask and use that to display certain details/properties about the current user that is logged in.

[@timewasterlee]

I‘ve watched a numbers of flask tutorials, but this one is the best one that express the core idea in such short time!!!

[@CI30]

Hi, i'm getting this error "wtforms.validators, invalid syntax" line 7 how can I resolve it. TIA

[@ArpanNeupaneProductions]

Can you show me the code that you wrote?

[@davidbidzhoian1527]

Well, I got ValueError: Password must be non-empty of bcrypt.generate_password_hash(form.password.data). I run the same code as you posted. What's wrong?

[@kurty85]

I did all the steps and they worked perfect but I am having an issue adding more routes to the home page for "about, cloud, etc". The routes simply do not appear when added. Anyone experience this?

[@MuhammadRakhaAlmasah-s9h]

RuntimeError: Either 'SQLALCHEMY_DATABASE_URI' or 'SQLALCHEMY_BINDS' must be set. How to fix it ?

[@lzmkalos]

TIP: you must declare app.config['SQLALCHEMY_DATABASE_URI'], before db = SQLAlchemy(app);

[@azyjmexcuseokstop924]

shouldnt the password be hashed from the client side ? as it is, the password still goes on the network uncrypted, and is only crypted when it enters the post function, server side, no ?

[@chitranshasiwal6791]

M getting a very different error..!!! Can u help me resolve.. Import "flask" could not be resolved from sourcePylance (reportMissingModuleSource) This is the only error I am getting

[@ArpanNeupaneProductions]

Can you paste the line that is causing that issue?

[@ArpanNeupaneProductions]

For importing Flask, you should write this: from flask import Flask

[@waynelei2187]

Hi, any idea how to setup the expiry or duration for he the cookie? Thank you! I think it should have something to do with the login_user method, but I am not able to make it work

[@edwardgyan9749]

thanks for all you do. your teaching is great and hope you continue to upload videos.

[@ArpanNeupaneProductions]

I’m glad I can help :)

[@HLD202]

Hello, I have a short question that you didn't cover it in your video, [20:55]: what is form.hidden_tag() use for?

[@ArpanNeupaneProductions]

CSRF token

[@himanshuS1718]

I am getting "Either 'SQLALCHEMY_DATABASE_URI' or 'SQLALCHEMY_BINDS' must be set" this error. can somebody help me?

[@martezcarmouche3179]

HEELLLPMy flask isn't working. When I hit run it gives me error "not recgnized as the name of cmdlet....". Can some one help!

[@harrisonshu634]

Awesome straightforward tutorial thank you!

[@ArpanNeupaneProductions]

Glad it helped!

[@Mackerr]

thank you for this, you saved my grade

[@jongolove6744]

The fact that you made this seem easy is actually impressive💡

[@LukeEdet]

How did you start up ya terminal after creating the database coz my terminal isn't working was yours

[@LukeEdet]

Pls can someone reply me based on this issue pls

[@SomeoneSexy]

I am having trouble with connecting to the database, when I run sqlite3 database.db, it says "the term sqlite3 is not recognized..." Not sure what I did wrong because I followed the same as your video. Send help pls! thanks!

[@AndreKaiqueDellIsola]

15:38 O erro "No module named 'flask'" indica que o módulo Flask não está instalado no seu ambiente Python atual. Para resolver isso, siga os passos abaixo: ### Passos para instalar o Flask 1. **Criar um ambiente virtual** (se ainda não tiver criado): ```bash python -m venv venv ``` 2. **Ativar o ambiente virtual**: - No Windows: ```bash venv\Scripts\activate ``` - No macOS/Linux: ```bash source venv/bin/activate ``` 3. **Instalar Flask e outras dependências**: ```bash pip install flask flask_sqlalchemy flask_login flask_wtf ``` 4. **Verificar a instalação**: - Você pode verificar se o Flask foi instalado corretamente executando: ```bash pip list ``` - Certifique-se de que `flask`, `flask_sqlalchemy`, `flask_login` e `flask_wtf` estejam listados. ### Reestruturando o projeto Certifique-se de que a estrutura do seu projeto está correta. Aqui está um exemplo: ``` my_flask_app/ │ ├── app.py ├── models.py ├── forms.py ├── templates/ │ ├── login.html │ ├── register.html │ └── home.html └── static/ └── styles.css ``` ### Arquivo `app.py` ```python from flask import Flask, render_template, redirect, url_for, flash from flask_sqlalchemy import SQLAlchemy from flask_login import LoginManager, UserMixin, login_user, login_required, logout_user, current_user from forms import LoginForm, RegisterForm from models import User, db app = Flask(__name__) app.config['SECRET_KEY'] = 'your_secret_key' app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///site.db' db.init_app(app) login_manager = LoginManager(app) login_manager.login_view = 'login' @login_manager.user_loader def load_user(user_id): return User.query.get(int(user_id)) @app.route('/') @app.route('/home') def home(): return render_template('home.html') @app.route('/login', methods=['GET', 'POST']) def login(): form = LoginForm() if form.validate_on_submit(): user = User.query.filter_by(email=form.email.data).first() if user and user.check_password(form.password.data): login_user(user, remember=form.remember.data) return redirect(url_for('home')) else: flash('Login Unsuccessful. Please check email and password', 'danger') return render_template('login.html', form=form) @app.route('/register', methods=['GET', 'POST']) def register(): form = RegisterForm() if form.validate_on_submit(): user = User(email=form.email.data, username=form.username.data) user.set_password(form.password.data) db.session.add(user) db.session.commit() flash('Your account has been created!', 'success') return redirect(url_for('login')) return render_template('register.html', form=form) @app.route('/logout') @login_required def logout(): logout_user() return redirect(url_for('home')) if __name__ == '__main__': with app.app_context(): db.create_all() app.run(debug=True) ``` ### Arquivo `models.py` ```python from flask_sqlalchemy import SQLAlchemy from flask_login import UserMixin from werkzeug.security import generate_password_hash, check_password_hash db = SQLAlchemy() class User(db.Model, UserMixin): id = db.Column(db.Integer, primary_key=True) username = db.Column(db.String(150), nullable=False, unique=True) email = db.Column(db.String(150), nullable=False, unique=True) password_hash = db.Column(db.String(256), nullable=False) def set_password(self, password): self.password_hash = generate_password_hash(password) def check_password(self, password): return check_password_hash(self.password_hash, password) ``` ### Arquivo `forms.py` ```python from flask_wtf import FlaskForm from wtforms import StringField, PasswordField, SubmitField, BooleanField from wtforms.validators import DataRequired, Length, Email, EqualTo class LoginForm(FlaskForm): email = StringField('Email', validators=[DataRequired(), Email()]) password = PasswordField('Password', validators=[DataRequired()]) remember = BooleanField('Remember Me') submit = SubmitField('Login') class RegisterForm(FlaskForm): username = StringField('Username', validators=[DataRequired(), Length(min=2, max=20)]) email = StringField('Email', validators=[DataRequired(), Email()]) password = PasswordField('Password', validators=[DataRequired()]) confirm_password = PasswordField('Confirm Password', validators=[DataRequired(), EqualTo('password')]) submit = SubmitField('Sign Up') ``` ### Verifique se todos os arquivos estão no mesmo diretório e executando o servidor Flask Certifique-se de que todos os arquivos estão no diretório correto e execute o servidor Flask novamente. Navegue até o diretório do seu projeto e execute: ```bash flask run ``` Se o Flask ainda não estiver encontrado, tente instalar o Flask explicitamente novamente e garantir que você está ativando o ambiente virtual corretamente: ```bash pip install flask ``` Certifique-se de que o comando `pip list` inclui `flask` na lista de pacotes instalados.

[@arnavghosh4242]

Great tutorial, but isn't it better to use UUID's instead of Incrementing Numbers for ID field?😄Great Tutorial, and I have Successfully Learnt Authentication in Flask in 26 mins.

[@its_just_me9]

its a great tuturial but i am lost at the classes of the form can we do this without them ?? can we just type it in html ??

[@MuhammadMuhsinYahya]

Very good explanation and well presented, thank you. But how about the styling the page

[@TheNishi42]

getting error while doing registration TypeError: generate_password_hash() missing 1 required positional argument: 'password'

[@vedkhetle7318]

dosent work!

[@keevo9194]

What extension does he have for his database.db file?

[@kamutabung511]

most simplest tutorial ever i watched, yet effective, super best tutorial

[@miguelfernandes657]

Thank you very much! Simple and effective!

[@ArpanNeupaneProductions]

Glad you were able to learn something!

[@muhammmadaditiyachoirunbas4614]

How do I create a database.db file whose format is still not SQL?

[@stanpedrieta105]

How do you show the validationerror message if the user already exist?

[@johnlloydfrancisco3401]

hello sir can you help me with my web app using flask, i need to create a point of sale for a pharmacy.

[@italobuitron1165]

I have a question with the @login_manager.user_loader def load_user(user_id): return User.query.get(int(user_id)) 1. When you log, the USERNAME is passed as user_id into load_user(user_id), right? then, 2. you use a User.query... (what i supposed is a query from Sql) which return the ID (in the DB) from the USERNAME So, if you use current_username.get_id() it return whatever u return from load_user(), in this case the ID from the query? is it?

[@jeanpeuplu3862]

Thank you so much, I use this at work and I am sooo grateful for this perfect tutorial! Thanks!!

[@allanmitala8104]

Man great video, I was struggling with a flask project but know am sure i can finish it. Thanks for the video.

[@ArpanNeupaneProductions]

Of course!

[@jonathan3488]

Hi after some trial and error it finally worked for me. However, I didn't understand how do I fetch the current user from the templates after the login. I see that the load_user() method is invoked every time I load a page, but I have no idea what to do.

[@ArpanNeupaneProductions]

You can do {{current_user.}} to get data for the current user. Ex: {{current_user.username}}

[@jonathan3488]

@@ArpanNeupaneProductions Oh thanks!

[@harshsharan4127]

what is your version of flask and werkzeug??

[@rodkafelipe6605]

watchout now: "Changed in version 3.0: No longer defaults to an in-memory SQLite database if not set. " Which throws runtime error, if SQLALCHEMY_DATABASE_URI is not set, right before the command db.createall()

[@sabinaanibassabinaanibas]

Thank you very much for great tutorial, but I want to change design of login page. I've made my HTML file, but I don't know how to combine it with your code from login.html, because there is only {{form.username}} etc.. Can you please help mi with customizing that HTML file? Thank you in advance!

[@ArpanNeupaneProductions]

Sure! You would basically make a normal HTML file in your templates directory and then you'd just render it in your Python file. Then you can add the {{form.username}}, {{form.password}}, etc as well and you can style it however you'd like.

[@Onlyhousefr]

Great value tutorial, thank you so much !

[@tinymicronano]

How to handle the validate_username and show the message in HTML?

[@azpycoder3337]

Dear Arpan Neupane, can you provide link to text version of this tutorial?

[@ArpanNeupaneProductions]

Hello, unfortunately I don’t have a text version for this tutorial.

[@Mrtero100]

Thank you! For me i had some troubles with bcrypt.check_password_hash, bcrypt.generate_password_hash so i imported them from flask_bcrypt and used the directly like : hashed_password = generate_password_hash(form.password.data) of course your method is very good and works but incase some have my same problem this can be helpful

[@ArpanNeupaneProductions]

Thank you not only for watching the video but also for providing a solution to viewers who may have encountered a similar problem :) Greatly appreciated!

[@georgejuarez660]

Nice video, but I would like to know one thing. I want the system to generate an error message (which is visible on the site) when the user in the registration puts the same email. Here I say how can I do?

[@rodrigomarchi9755]

Great tutorial. I just wish you had a more comprehensive tutorial as well, creating a production ready app with more complexities involved.

[@ArpanNeupaneProductions]

Great suggestion!

[@sushantthapachhetri7225]

bro i have a question, where will the raise validation message goes,it is not showing message "Username already used" though it is working....??

[@ArpanNeupaneProductions]

My apologies, I forgot to include that in the video. To view the error message when a validation error is raised, you can do this in your HTML template: {% for error in form.username.errors %} {{error}} {% endfor %} You can write those lines in both the register and login templates. If the program encounters a validation error (ex: username already exists), it will display the error.

[@sushantthapachhetri7225]

@@ArpanNeupaneProductions Thank you!!

[@ArpanNeupaneProductions]

@@sushantthapachhetri7225 Happy to help! 😁