Factory Design Pattern - Advanced Python Tutorial #7

[@alexd7466]

That is probably how you would do that in Java. But in Python we just use a function that returns the object. You can already see that because you made it a staticmethod, and a class with just one function (and even worse a staticmethod) , is a clear indicator that it should be a function, not a class.

[@abebuckingham8198]

Dictionaries are a kind of function and work really well for dispatching.

[@abebuckingham8198]

For factories I prefer to use a dictionary with the key strings and the value being the class in the build_person to avoid the cost of comparison as follows def build_person(person_type): PERSONTYPES = {"Student":Student, "Teacher":Teacher} return PERSONTYPES[person_type]().

[@munteanionut3993]

I think behind the scenes there is still a comparison being made - in basically the way indexing a dictionary (ie: PERSONTYPES['some_key_string']) works. But yeah, doing it like you looks prettier to me, too

[@breakdancerQ]

Hell yeah

[@PeaceToUsAll]

@@munteanionut3993 no comparison there, it is just the relation between a dictionary (PERSONTYPES) and its key (person_type) dictionaries have a complex but time efficient method of fetching values (using hashes), you can read more on that.

[@srs32896]

Would this be preferable to using eval(f”{person_type}()”), and it so, why?

[@martinbel]

great solution! This is better

[@manifaridi9200]

You proved programmers can also have biceps 💪

[@raymondmichael4987]

These pattern tutorials are gud, please we need more and eventually creating a project with one

[@mr_robot_tech]

I was trying to understand this topic since past one week and watching multiple videos was making me more and more confused. I understand it through this video. Thank you for explaining so well in this video.

[@arthur6999]

day two: async/await tutorial

[@tips1483]

Yes please I understand the idea but when trying to use it I lose brain cells

[@tips1483]

@Rudy Rayden mmhm sure I see that you both decided to make your account 3 weeks ago stop.

[@bhaveshvaishnav7388]

Explained with such a simple way without complicating anything. Awesome!!

[@kevinjones238]

The clarity of your explanation/example of the factory pattern is awesome!!!

[@iiStxrii]

Hey man, I know you don't have a lot of views yet, but when programming becomes a core subject in schools, you'll be the khan academy of the future. Keep on the grind G

[@ptyspawnbinbash]

Thanks for all the valuable videos, supported you by buying all the seven books. :)

[@pythonisthebest358]

You’re unbelievably cool! Keep up the good work!

[@ddjambel]

You need always self in a object, because self, it the object itself, to use all attributes or methods, over "self.". Cheers from Germany.

[@jrgomez]

Great explanation as usual. I'm defintively a rookie on OOP, but I'm learning a lot. Thanks !

[@golammuhaimeen2825]

that was a really nice and simple example man. thank you so much. cleared up my understanding of a factory design pattern

[@heroicrhythms8302]

instead of hardcoding "student" and "Teacher" values, you can use an ENUM

[@deeprony7]

Having the if-else logic still reside in the ConcreteFactory violates the Open-Closed Principle. Would it be better to have an interface for FactoryPerson and implement Student and Teacher from it? If so, how would that implementation look like?

[@hasibislam4421]

I'm really liking this advanced python tutorials......Can you please make a video describing what meta classes and how they work?

[@Custom-Tkinter]

Which text editor are you using bro???

[@dpm-07]

can anyone tell me difference between Factory Design and Abstract Factory Design ?

[@jerielmorales1726]

Great Tutorial. Part 2 of Vim course next =)

[@gauff3r]

helpfull, thanks, I'd rethink the use of conditions in factory

[@Jovana_bp]

thanks for simple and good example

[@_indrid_cold_]

Awesome! Really good examples and explanations. Thank you!

[@rsc8295]

You could actually add to that to create an automated conversation, like a code people could use to find details of a student or teacher. You would need to add the next prompts and conditionals and include perhaps some code to read in data from file, it would take a lot of time for all the possible responses but be really cool. In fact might do this as practice for my exam. Otherwise cool tutorial!

[@wariare12world95]

building a person sounds scary!

[@NeuralNine]

>:D

[@julietatallaferro2072]

great teaching :) thank u again!!

[@travelcinematically]

Explained so beautifully 🤟🤟

[@pratheek5096]

Perfectly explaineddd

[@andrejk9523]

A combination of __Init_subclass__ and __new__ implimented in the master class would be a better implementation

[@dmitriyobidin6049]

Good tutorial, but missing one part that can be helpful - factory also can be instantiated from IFactory interface, cause in some cases we need different concrete factories, depending on user input.

[@AnIceCrasher]

Really well explained! Thank you.

[@JeffreyMyersII]

nicely explained, but i have a question. isn't creating factories a use case that the ___new___ class method was made for?

[@naserghodsian5545]

In an statically-typed language like Java you make an Interface to have control over the output of builder method in the factory class. Given the fact that in Python the builder method of the factory class can return anything, what is the point of having an abstract class here?!

[@aniketpurohit8613]

This is a tremendous playlist. Looking for async/await video.

[@chongsun7872]

One quick question is that, in the Person object, the person_method is an abstract Static method. In student and teacher object, you can rewrite it as a normal method? Is this allowed in Python?

[@garfieldgray6746]

Thanks for your brilliant video, I've got a question, In the last lines of your code, "person" is a class that we've determined dynamically, then must be able to instantiate an object with it right?! Like pp=person() But I just can't:/ Do you know why?! Thanks 🙏

[@burakhanaksoy]

Thanks for the tutorial. A personal comment is instead of making if check inside a single @staticmethod, it'd be better to create multiple static methods. In this way if you want to create another person, say engineer, you wouldn't have to make an if check.

[@ishfaqbabar2355]

Which Code Editor are you using .

[@girish6064]

Thanks for sharing!

[@alperklc7782]

What is the difference between ABC or ABCMETA class? Can we use one instead of the other? Thanks for the lesson.

[@munzutai]

What I've never understood is what's wrong with doing it without a factory? What are the benefits of using a factory?

[@falklumo]

You want to hide the subtypes. There is normally no need to expose subtypes to client code. Therefore, a factory is required.

[@suche_cz]

Thank you for video: Is possible to mix interface class with factory class ? eg.: It works, just if it''s not some bad practise. class Person(metaclass=ABCMeta): @abstractmethod def person_method(self): """ Interface method """ @staticmethod def create(person_type): person_class = { 'Student': Student, 'Teacher': Teacher, } return person_class[person_type]()

[@val8801]

I see your video only for you awesome intro :)

[@ytalodossantosamorim3052]

Are you using the terminal to write a script? If yes, .......how

[@andytheodorko9874]

Wouldn't it be a better example if the logic of creation of a Person in a Factory be more complex? (add random, multiple parameters)

[@A_Xavien]

In your example it's more like factory method than just factory if `PersonFactory` would have other actual methods. Also why use `if else` (in `build_person` method), when you can just create some dict that store name-class relationships (which name corresponds to which class)?

[@melokorn]

Really useful. Thanks

[@Liproqq]

Super tutorial. Würdest du empfehlen auf's englische keyboard layout zu wechseln?

[@hoangphan2429]

I love your videos, but I think the example code for the abstract class should be improved. The code doesn't represent the implementation of an abstract class. In PersonFactory class, it basically returns the class.

[@someonemight]

What's the benefit of doing this vs just having a utility function?

[@ruslanways]

what IDe did you used?

[@danielg.campos9662]

Thanks so much for the tutorial, btw, i have got this message in the pyCharm : "abc.abstractstaticmethod' is deprecated since Python 3.3. Use 'staticmethod' with 'abc.abstractmethod' instead" so i have to replace it with : "from abc import ABCMeta, abstractmethod" and then in the class : class IPerson(metaclass=ABCMeta): @staticmethod" and it did the work. Any comments on that? thanks again

[@pawepuciennik6604]

I don't understand, what is it abstract class for? The whole factory would work without it.

[@nopens]

This. I get it you might wanna double check that every subclass of IPerson has its own imlementation of person_method. Maybe its useful when you have too many subclasses to keep track of them and making the base person abstract would raise an error, maing sure you can safely call that method on every child?

[@macieks3604]

And why is it necessary to use abstract method here? It would also be possible to have one base class and 2 child classes with same method name overriding the method of the parent class, so called polymorphism. There is no need for an abstract class here. I've seen many examples of an abstract class used in that way but I still don't understand why it was used....

[@pegasus-weilsicherheitdiew5278]

How can i ensure that an other coder uses the interface to create objects and not the subclass directly? Can i set a class to private for other modules? Like private or public methods?

[@alexd7466]

no

[@falklumo]

The factory could use a secret to initialize the subclass not available public. Unfortunately, Python as a language is not expressive enough to support all the famous design patterns directly.

[@TheDigitalSight]

Which fonts do you use?

[@Ricocase]

Rotate video to see? Video start at 2:10. Where's else for printing error? If input is == "student" print "I'm a student?" What's the main and init?

[@rafaeel731]

Why to create a factory class when you can, for instance, create a function to do the same?

[@os_.mos_.m9346]

What is the name of the song you are using in the intro?

[@klipkon1941]

Why are they static methods?

[@cahitskttaramal3152]

it was a great and simple tutorial could you also more design patterns if possible?

[@a1dgha1]

How come you haven't upgraded your Python to 3.9 yet?

[@user-sy1sg4ws3y]

This is Simple Factory?

[@franciscolucarini8761]

Hey bro will you do differences between python2 and python3 regarding bytes format, thx in advance

[@nopens]

Doesnt work in python 3.8.3 if you pass "meta=" instead of "metaclass=".

[@pythonicd1239]

Thanks man! That helped!

[@__3093]

you're getting more viewers

[@ninjacodertech]

possible tutorial: how to make VPN in python pls try to make

[@Pyrografpl]

Thank you

[@armans4306]

Bro can you give. some vim tutorial with python. I really like your setup.

[@andytheodorko9874]

I'd use 'born_person' 8:12

[@z4ramoth]

more pattern vids please !

[@alialavizadeh2775]

so useful tnx

[@ahmedossama7738]

Great!

[@falklumo]

Shouldn't you mention Erich Gamma et al. and their book "Design Patterns"? After all, the patterns are language-independent and this is just Python trying to catch up 25 years later ;)

[@julianreichelt1719]

nice one

[@01akbarikrunal24]

ya i learn lost of thanks

[@sachinpadwalkar8446]

Please upload your vim plugin setup 🙏

[@NeuralNine]

It is already on github

[@sachinpadwalkar8446]

@@NeuralNine can you tell me the names of all the plugin that you use ?

[@NeuralNine]

@@sachinpadwalkar8446 all the names are in the github file? Why do you want me to list them here in the comment section manually?

[@sachinpadwalkar8446]

@@NeuralNine oh found it thanks

[@ViralKiller]

appreciate the tutorial but completely useless and overcomplicates things for no reason...definitely wouldnt be allowed at my company....way too many dependencies and separate classes for such a simple program

[@falklumo]

You haven't seen big projects. Python doesn't do big projects for a reason ...

[@kaya12892]

python in minecraft +1

[@undergroundbodega9766]

Gives and example then said “ this is not factory…”. What the point of that. I wish videos were straight forward.

[@tips1483]

1st

[@NeuralNine]

yes ^^

[@tips1483]

@@NeuralNine funny enough the video took so long to load I originally typed “2nd” but when I realized I was genuinely first I edited it lmao

[@winartoit]

i dont know

[@destiny_02]

12th

[@SergioInToronto]

Yikes. Bad patterns like crazy. Don't return -1, raise an exception! Class PersonFactory is useless - just write the function! Classes which don't save state are effectively just namespaces, but that's what files are for!

[@vascof614]

1st

[@tips1483]

Nope beat you