Python Flask Tutorial: Full-Featured Web App Part 6 - User Authentication

In this Python Flask Tutorial, we will be learning how to add users to our database. We will then create an authentication system so that users can log in and log out of our application. We will be using the flask-bcrypt and flask-login extensions to help us with this. Let's get started...

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#Python #Flask

[helloworld]

11:43
Corey: "This is the first time we see an error screen like this"
Me:*nervous laughing* "Yeah first time"

[blueboystudios]

To anyone reading this, I want to say that these tutorials are much much better than any paid content on Udemy, etc. Corey, I cannot thank you enough for all your efforts and patience in creating this amazing content. I am currently unemployed and I'm trying hard to learn full stack dev on Python and upskill myself . I promise I will contribute to your channel the moment I receive my first salary. I mean it. Once again, thank you so so so so much for everything you do Corey. May god bless you.

[bugs]

For anyone wondering how validate_username() and validate_email() are being called, these functions are called with the FlaskForm class that our RegistrationForm class inherited from. If you look at the definition for validate_on_submit(), and from there, the definition for validate(), that validate function contains the following line:

inline = getattr(self.__class__, 'validate_%s' % name, None)

There is a lot going on in the background, but from what I can tell, Flask is checking for extra functions created with the naming pattern: "validate_(field name)", and later calling those extra functions. Correct me if I'm wrong.

[ebiscaia]

@9:55
The 2023_c version is:
from <app_name> import app, db
app.app_context().push()
from <app_name>.models import User
user = User.query.first()

[dmcg]

These are excellent videos. Its not a step by step as that would be A-Z with no issues. He brings you through all of the concepts, and shows you why things need to be done a certain way by highlighting errors and sometimes making them on purpose. Great teacher

[carlfranz]

At around (34:00) or so as you are putting in the logout stuff, you could also use:

<a class="nav-item nav-link" href="/logout">Logout {{current_user.username}}</a>

in the layout.html. This will display the userid you are logged with. When you are testing, it's REALLY nice to know who the heck you are logged in as.

[kli]

Corey It was great to meet you at Pycon! I really appreciate how you incorporate important knowledge gems throughout the tutorial so that we understand the reasons behind the steps and potential problems that may be encountered. And yet manage to avoid the clutter. Thanks so much! To show my appreciation, I donated via paypal :)

[howards]

These tutorials are so thorough... Covers so many cases that other tutorials just brush over or simply skip. Thank you SO MUCH!

[slavoie]

28:01 Just wanted to point out a little shortcut: there is no need to add an "else" statement after hitting a "return" statement inside the previous "if" on line 53. Since the function will return, the rest of it will not be evaluated after that point. This is obviously no big deal, but it is a small detail that's useful especially when trying to maintain the length of the lines under 80 characters since you end up with less indentation!

Thank you Corey, I'm learning a lot from this series!

[EMPured]

Corey, your tutorials are gold. I'm having real fun following along and it makes me excited to be programming an actual website. The videos are a constant bombardment of useful information. Good pace, good content, good quality. Thanks for the series on flask!

[uselessgarbagehandler]

For anyone wondering why the navbar login/register links are left-aligned, it's because you might be using Bootstrap 5. Simply add the div class ms-auto next to navbar-nav.

[campaignguy]

"Hey there how's it going everybody"

[kaushalkhokhar]

Whenever I think to write a comment on this. I need to think with what words should I grateful to Corey. All things that you explains are much much cleaner and clear. So happy and thankful to you.

[sribastavrajguru]

I wish I could give thousand likes in this videos, these contents are much better than most of the paid contents available. Thanks a ton Corey for making our lives easier thru these awesome tutorials

[fabiodeabreu]

11:42 "This is the first time we've seen an error like this"
that actually made me laugh I've had at least 10 different errors page only in those first 6eps.

[TechTribeCommunity]

Outstanding video! Thank you so much! I am a high school senior working on an engineering capstone project. We are making a tool to facilitate people's college applications. Since it uses machine learning, we chose Python over PHP for this task, which makes Flask very useful. Your tutorials on the login system and database have been extremely helpful (I originally did some MySQL queries by hand, but this is much cleaner and easier). Cheers!

[waronamogobye]

thank you so much! I'm 15 and I've been struggling with this thinking it's high end programmer ish...but your explanation helped me a lot❤. Everyone deserves a teacher like you💖God bless u Corey

[AymenLagha]

I don't know why I feel proud when corey's server stops running and mine doesn't

[enduringpromise]

There is a ton of information in this one video. I am going to have to watch this one over and over while building a site. Some of the things that these classes and functions are doing is confusing and it would be helpful if you explained how they function. Thank you for creating this video series.

[ThePasupathi]

Corey..Not sure How much research you have done...Excellent presentation