But how do DJANGO signals work?

Learn the fundamentals behind Django signals in this one.
Code: github.com/codingforentrepren...
Ref: docs.djangoproject.com/en/3.1...
Time & Tasks 2 Project: cfe.sh/projects/time-tasks-2
Have a question? Let me know in the comments.
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0:00:00 Welcome
0:01:33 Examples of Model Instance Events
0:04:48 User created pre_save & post_save
0:15:50 Practical Example with Custom Model
0:23:40 pre_delete & post_delete
0:26:53 Bonus
0:35:15 Thank you

[@divakaryadav2265]

4 years ago I got into IT because of you and surprised to see such less subscribers. you deserve a lot more.

[@CodingEntrepreneurs]

Thank you but hearing you got into IT because of my videos is worth 100mil subs.

[@niyasmohammed046]

Hi DIvakaryadav shall we connect on LinkedIn?

[@concrete4054]

Would be cool, if you could go deeper into how to structuring larger applications in a sailable and maintanable way. Including folder structure, business logic, validation... There are a lot of beginner tutorials. But it is much harder to find advanced tutorials.

[@jesseinit]

I really second this. Everywhere you go to is a bunch of beginner vidoes...We could use a bit more complexity right now

[@sarveshyadav01]

yeah man actually needed!

[@alexy.3512]

Two Scoops of Django 3.x

[@JA-ur8ob]

As this post is 2 years old, keen to know 2 things: 1- Did you guys get a decent job or create a decent website that scaled well? 2- Maybe you can now answer your own question for me? I've been working on a large django project for 8 months and now have to make a massive database change because of a database design flaw. It'd be good to hault my progress and learn scalability concepts before I continue to prevent this from happening again. Thanks

[@codegeek8256]

This is a very good tutorial, i would suggest you make it a series whereby you cover this kind of Django specialized concepts that are not usually covered in general tutorials. You pick them same as you picked signals and focus only on them per video. it would have been nice if you also cover m2m signals. Thank you.

[@fathiabdelmalek6203]

Thanks. Thank you a lot. Thank you so mush. I have searched for two weeks for that, and finally find it and understand it. Thank you

[@ahmed_mokhtar486]

Your explanation is very clear and straightforward to understand the logic. Thanks

[@rafafi7213]

Thank you for the help understanding signals! helped me out a lot. caught you slipping there tho at 17:02.

[@TimePasser]

You are amazing. Thank you very much for the effort of teaching in very simplified way. Iam learning a lot from you. Thank you.

[@pawankushwah4992]

Very good and simple explanation.

[@brhh]

I would like to see a deep dive into Channels because there seems to be little to no in depth explainations with the same way you present the details which is so unique and understandable

[@shaxzod6485]

Thank you bro for the amazing content)

[@dikimuhamadsyidik9650]

Thankyou justin this is helpful

[@bobtanner5151]

Deep drive into full stack testing. Testing views, models, forms, etc.

[@salmanmammadli]

Thank you very much man.

[@ellawhitestone]

Thanks my dear brother... Very good examplez

[@hellosingh4408]

Very helpful video

[@user-si3yb1ps3i]

thx very much for subtitles

[@kwakukarikari8095]

Very good explanation.

[@youssefel-shabasy833]

great tutorial, keep it going :D

[@khalednur9229]

thanks for sharing this idea. you help me a lot!!!!

[@joy_sam_raj]

Thanks a lot.. Well clear explanation

[@mhmmdmustafayev8216]

best explaination

[@tomaszscierski7351]

Great job, thank you

[@JoseLuisMorales]

Best signals introduce for beginners ever 🎉😊

[@idrisrampurawala]

Nice tutorial as always 😉 Thanks for sharing. I have one query regarding usage of signals in a distributed environment. Let's say we are running django in multiple processes via docker or something and these signals are run inside the same process in which the model was created. So how to handle scenarios for failover. Like if the process got crashed without executing let's say the post save signal. And when it restarts, the signal is lost but model got saved. Any ideas on these scenarios?

[@MainulHoqueHira28]

awesome video

[@tajbinkhan4858]

Hi sir, Big fan of you and your tutorial. I have a request on Django framework. I have searched KZbin and google about booking system with Django. But I did not get proper instruction how to do that. If you upload tutorial about that, it will be very grateful. Thank you, sir. 🥰🥰🥰

[@Morteza7220]

thanks

[@johnathanjames2872]

About adding slugs to an instance, doesn't using signals seems a little bit overkill, I mean I'm always overriding the save() method in the Model, check if there's a slug on the instance, if not, slugify the title, add it as an attribute to the instance and call the super save

[@Techiesse]

I understood how to use signals. That was a great explanation. Thank you. I'd like to place a practical question, if I may: I don't see why I would implement the behaviours on BlogPost using signals. Why not override the save method (for instance) on the model itself? It seems to me a much cleaner workflow for the example you presented. By overriding the method I'd have all the class related behaviour in one place under the umbrella of the class itself. I can see the utility for signals when dealing with a layered architecture and I don't want to inject code of a higher layer into a lower layer (which shouldn't know anything about its clients). The first example, triggering actions based on User creation, matches perfectly this scenario. I know your intention is to bring a didactical example to showcase the signals. I'm just elaborating on this on my side. Congrats for the great content!

[@CodingEntrepreneurs]

Thanks. Here are my thoughts on this exactly : www.codingforentrepreneurs.com/blog/post-save-vs-pre-save-vs-override-save-method

[@CodingEntrepreneurs]

I haven’t changed my view on this either :)

[@CodingEntrepreneurs]

And the official docs: docs.djangoproject.com/en/3.1/topics/db/models/

[@Techiesse]

@@CodingEntrepreneurs Hi, thanks for replying. I read your blog post. I think the example you mention there is similar (you provide handlers for a class defined in another file) to the User example you use in the video, which for me is ok. What is making me think is the Blogpost model. In this case I'm trying to figure out what makes more sense.

[@JoseNavas]

Thanks for the tutorial. Any chance you update your DRF course on Udemy?

[@onlinetimenow1647]

what's the best way to implement dependant drop-down chained field in a django form(like: country->city and category->subcategory) retrieving data from db. i personally have difficulty to get the response back and populate the field(although i followed some examples but not happening). thank

[@dilipsai909]

did you try smart_select library?it has a chainedfield functionality

[@csandreas1]

Please make a video about business logic in django. Some people believe that business logic should be in the Models

[@LucienDadaKYABU]

Great Tutorial! Helped me achieve some King of business logic in an Invoice and Stock Management System. But How To notify user in a django template in realtime like maybe the user x has been deleted or Added ?

[@CodingEntrepreneurs]

Make a notifications app with models for the user

[@CodingEntrepreneurs]

There’s a third party one called Django-notify I believe

[@usamahussain4461]

got question. Instance is not given an ID until you save it. But how is the condition working in blog_post_pre_save() model?

[@grandlibulu3701]

Can you cover Signals for foreignkeyfield

[@shivamdubey4783]

can we use django signals to send notifications also

[@mohammedfareedh]

So Justin Bro, This acts like a trigger that is used in relational SQL tables servers like Mysql, PostgreSQL and etc

[@bhutanpythoncoder]

Thank you for the great content. Will django signal works if i have to give access to students which was registered by teacher in school management system. Haven't seen tutorials taking about this. I would be very grateful if you give some idea. Thank you 🙏🙏🙏🙏

[@CodingEntrepreneurs]

The Signals I used based on models, not users. So you can use it for what you’ve said. Why not experiment on your own?!

[@bhutanpythoncoder]

@@CodingEntrepreneurs Thank you so much sir. I learn a lot from your channel. May you reach million subscriber ASAP.

[@nextgodlevel4056]

he is not a teacher, he is more than a teacher the way he teaches is awesome

[@ajinzrathod]

21:25 Would be good if you included that video link in description. Couldn't find it.

[@CodingEntrepreneurs]

You're right. It's here cfe.sh/projects/time-tasks-2 Thank you

[@ajinzrathod]

@@CodingEntrepreneurs Thank you so much ♥♥♥♥

[@litDevYT]

Never dissappoints like always

[@ceswest1223]

how can I implement django signals in docker?

[@tinoutech5016]

Why signals work only when we put them in the models.py file?

[@ajinzrathod]

25:22 He says, "actually that doesn't cover all types of delete". That means that when you delete multiple objects(using multiple checkboxes in django admin), def delete () would not work there. It only works on single object. Hope this clears someone doubt.

[@poonamyadav7552]

Is this same process,if our project is live

[@baldeagle6531]

Please help me, signal m2m_changed post_remove does not work for me

[@deepbhut1922]

hey.. sir is it work django with mysql database

[@poonamyadav7552]

Is this same process,if our project is live

[@hiromsantosh4215]

Is server side rendering possible with django, if then plz do a tutorial :)

[@brhh]

I believe django already uses server side rendering for the templates, they are giving them raw

[@LifeIsCrazyAsShit]

Here is some challenge i guess How to pass additional data to the signal For example we have default user model and while user registration we are also asking for some additional data like phone number, DOB, etc ..these additional data needed to pass to the signal

[@Brother_rafael356]

im still confused as a first timer learning django but im less confused compared to 45 minutes ago thanks

[@sachinjadhav8252]

Why Python Ecommerce.com site not working?

[@ashrf8050]

🥰

[@dhavalsavalia]

NSFW warning at 17:00 xD

[@shivampratap8259]

i literally came down to type that thing XD

[@jasonk4614]

17:02 :)

[@aksjin8929]

.

[@neildutoit5177]

Video title: "But how do DJANGO signals work?" Video: "Here's how to use Django signals" Nice clickbait.

[@saeedmhmoud109]

Translate for Arabic please