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What I love about Django

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Re: What I love about Django

#61

Post by tclancy »

phn wrote: post #43

The only part I don't really agree with, is the avoidance of app separation and signals. It's one of the cleanest ways to decouple your modules and keep some level of sanity in a medium-sized codebase. It comes down to deciding what parts really need to depend on others and be very explicit about that. I generally end up with a few core apps with the main data objects that a lot of other "parallel" ones depend on, a…

I always wonder about signals. I found them incredibly attractive from a code cleanliness standpoint, but every team I’ve joined avoided them either because they got burnt by them or because of superstition from blog posts by people who got burnt by them. It may be a cognitive load thing, that in smaller codebases it’s easy enough to remember “these three things fire a signal when saved”, but bites you in the ass when trying to make a quick patch for a bug in production late in the day because a customer called up screaming.

Re: What I love about Django

#62

Post by ErroneousBosh »

rtpg wrote: post #59
kitsune_ wrote: post #39

Earlier quoted context omitted.

The ORM is really not good in my opinion because it is ActiveRecord'ish and has all its downsides. I wouldn't use Django for any moderately complex domain. But even with simpler CRUD style apps I don't really see the point in it.

The one thing I really appreciate with the ORM is that you really can get the ORM to make... more or less any sort of SQL query you want. It can take a while to wrap your head around what fields get used in aggregates and the like, but when working with big models with like 65 fields and juggling a bunch of stuff, not having to futz with serialization/deserialization and "just" expressing your problem in the dumb way…

> The one thing I really appreciate with the ORM is that you really can get the ORM to make... more or less any sort of SQL query you want.

And if you can't make the ORM make the SQL query you want, you can just write it as a SQL query, like this godawful monstrosity:

      x = Site.objects.raw("select id, name, lat, lon, 111.045*degrees(acos(cos( \
        radians(latpoint))*cos(radians(lat)) \
        *cos(radians(lngpoint)-radians(lon)) \
        +sin(radians(latpoint))*sin(radians(lat)))) \
        as distance from sites_site join \
        (select %s as latpoint, %s as lngpoint) as p on 1=1 \
        order by distance limit 5", [float(lat), float(lon)])
... which calculates the Haversine distance from where you are now to the five nearest points.

I am in roughly equal parts proud of and horrified by this creation.

Re: What I love about Django

#64

Post by tclancy »

zelphirkalt wrote: post #48
Klonoar wrote: post #19

I feel sufficiently old after having read South in this article. Good god what a throwback. Django is hands down one of my favorite frameworks ever created, and the only one I still reach for in some contexts. For a lot of projects I use it to drive database migrations, and stand up an easy admin portal for others to use - then anything else is driven by an API layer written in (e.g) Rust. I haven't had to care about…

How do your API calls get into the Django app(s)? Do you define the API as well on the Django side (duplicating the API)? Or is there some tool that translates the Rust API calls for Django efficiently?

Going to guess they explicitly map the database tables (and do it all as read-only perhaps) to allow admins to view and report on data from the API.

Re: What I love about Django

#65

Post by tclancy »

whateverboat wrote: post #28

I really like django, but since being involved in it from early days, whenever someone now praises Django, I am reminded of this talk: https://www.youtube.com/watch?v=i6Fr65PFqfk DjangoCon 2008 Keynote: Cal Henderson

I too often think of things as frozen in time two decades ago.

Re: What I love about Django

#66

Post by ErroneousBosh »

DarkNova6 wrote: post #26
matsemann wrote: post #16

I really like the ORM and the migrations, but some parts I really dislike. They're maybe not Django's fault, but how it's used most places: * Models being passed around everywhere, queries happening everywhere. I prefer having a dedicated service/selector layer to do those things. Then convert to pydantic objects or something that's passed around further. * Corollary, but adding stuff to querymanagers quickly goes ou…

I seriously don't get why Django ORM is using the Active Record pattern. This is such a stupid footgun that trivially causes horrible performance and BEGS you to cause n+1 problems. Never in my life did I have a problem with lazy loading causing unbearable performance until I joined a Python Django team. I really tried to find sympathy for the "dynamically typed" folks (please spare me saying Python is technically st…

What would you have used instead?

Re: What I love about Django

#67

Post by Klonoar »

zelphirkalt wrote: post #48
Klonoar wrote: post #19

I feel sufficiently old after having read South in this article. Good god what a throwback. Django is hands down one of my favorite frameworks ever created, and the only one I still reach for in some contexts. For a lot of projects I use it to drive database migrations, and stand up an easy admin portal for others to use - then anything else is driven by an API layer written in (e.g) Rust. I haven't had to care about…

How do your API calls get into the Django app(s)? Do you define the API as well on the Django side (duplicating the API)? Or is there some tool that translates the Rust API calls for Django efficiently?

In practice, I've found you never want to be duplicating full models on the API side - you're only querying specific fields so you end up with custom/ad-hoc structs instead of ORM objects like you'd have in Django.

Just read from the database and treat Django as a DB builder/migrator/inspector.

Re: What I love about Django

#68

Post by tclancy »

thraxil wrote: post #36
0x4d4c wrote: post #13

I remember, when I used it for the very first time in commercial project. Client briefed me in the afternoon, the next day, before the noon, she got ugly app, but with fully working admin backend. She was sold. But I also remember, that some non-standard requirements were really difficult to implement or get around. Having that in mind, the next project was entirely in Pylons. All was good, until we were asked to add…

> Having that in mind, the next project was entirely in Pylons. All was good, until we were asked to add Unicode support. How long ago was this? I feel like unicode has kind of been a solved problem in Python since python3 came out. In the python2 days it was, indeed, miserable.

Pylons was a long time ago. Definitely Python 2. The era just after (?) or maybe same as TurboGears and CherryPy.

Re: What I love about Django

#69

Post by ErroneousBosh »

zelphirkalt wrote: post #45
Oxodao wrote: post #33

Earlier quoted context omitted.

I despise django-orm, doctrine is so much better. Like, who thought that using named arguments to do stuff was a proper way ??? `.filter(created_at__gte=XXXXX)` why? The rest of the framework is great but the ORM is definetly its weakest point.

I find those double underscore kwargs weird too, and would prefer to simply pass a lambda instead. What is your idea, what would you suggest?

The double underscore kwargs are a bit odd, I agree, but once you know about them they're okay.

And, rather like the petrol engine, it turns out while it sucks, everything else is massively worse in some vitally important way.

Re: What I love about Django

#70

Post by giancarlostoro »

fmind-dev wrote: post #58

I'd love Django, if they had a better async story ... I used it for a recent project. While the framework is overall amazing, I had to switch to Go for better performance and easier async support.

Django-Bolt is one of the interesting projects I found recently that helps boost RPS for Django by handling HTTP requests via Rust.

https://github.com/dj-bolt/django-bolt

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