Where i must create classes in order to manipulate data of the database?
I have 4 app in my project. Can i create an app specially for that, and create all the classes/functions in the models.py ?
The better approach is to have each app its own models.py. which would define the database tables each app is using.
And to have each app its own views.py. which would define the logic of the app and manipulation of the data of your database.
I don't think you really understand what apps really are in Django and you can learn about them in here look at other answer and mine too.
yes, it's recommended to create your models in each of your apps directory for reusability.
edit* check out this answer if you're wondering how to implement singleton in django,
Related
I think I am looking for as much advise as possible.
I have a project that I have inherited. The codebase is absolutely awful. I have a Django project, within this a React app. There's all manner of proxies between to fetch from the API to deliver up content.
However, I want to start to re-write the API, as it is awfully put together. Zero documentation.
To re-write the API, I would like take a copy of the exisiting database - and then work with this to write a more consistent API.
What would be your advise/steps/method to achieve this, and what should I look out for when doing this?
N.B. The database is PostgreSQL.
For this Django itself has the inspectdb command.
It will inspect all tables, fields, and foreign-key relations and then create unmanaged models for you. You can fix them manually with (perhaps) missing foreign-keys and then use them in django-rest-framework.
I have followed various posts and tutorials but couldn't find anything that is relevant. I found a ORM for rethinkdb "https://github.com/dparlevliet/rwrapper" but don't know how to use it?
I am new to to django and python.
It depends on what you want to do.
There is no way to simple replacement of Django's ORM with RethinkDB now. However, working with RethinkDB driver is simple enough, and similar to how you would use Django ORM.
The nearest thing is indeed rwrapper, you can try starting with this tutorial.
If you don't need to use Model classes, then you just need to find a place to connect to database (or use some sort of Singleton or Factory to connect to the database), and then just import rethinkdb as r and r.connect() and then just write queries with ReQL.
If you need realtime data, then Django is not suitable for that at all. You can consider mixing Django with Tornado
Django doesn't support RethinkDB at the moment and I don't think there's any plan for it as well.
Django developers don't add new stuff to the code base just because it's something new and might be cool. It should be really well mature and a high needs for it. So, I don't think you'll be hearing anything about RethinkDB from Django devs anytime soon.
This project might be something interesting:
https://github.com/thejsj/django-and-rethinkdb
In order to use any database with Django, the adapter should completely be a Django DB Backend in order to work with:
Models
Admin
Forms
Various Class Based Forms
Session
Auth
etc...
In others words, as long as the db backend doesn't support all the django database operations is not something that you wanna use.
I'm starting to use Django and I'm really impressed by the possibility of automatically creating views from a model.
So, I'd like to know if there is such functionality on other web frameworks. I know of RoR scaffolding, but that is not quite the same thing, since you need to change your views manually in case you change the related model.
For those who are looking for an answer here, perhaps django-baker (https://github.com/krisfields/django-baker.git) will do what you need.
pip install django-baker
Then add django_baker to INSTALLED_APPS and run
python manage.py bake your_app_name
Note that previously you need to remove urls.py and views.py from your app so they can be generated.
Then it will generate all the skeleton stuff.
https://docs.djangoproject.com/en/dev/topics/class-based-views/
I think I've found one possible solution. The concept is called model drive development. There are quite a few java frameworks that provide the ability to create a, rather simple, application directly from the model. This post presents some of them http://www.javaneverdie.com/java-frameworks/java-domain-driven-frameworks-review/
I am building a web interface for a database at my school. The database will hold our school's versions of academic standards.
When you build a site using django, does it create a clean database? For example, wysiwyg website builders like dreamweaver create ugly html and css code on the backend. I would hate to see a similar degree of auto-generated cruft in my database.
Should I create the database myself and then build a django site to access the database, or go ahead and let django create the database?
Under any simple to moderately complex application, Django will do a fine job creating the database for you. I've yet to run into any issues with what it's made.
I would suggest that you use South to handle your table migrations. And use virtualenv and pip to set up and maintain your Django environment.
You can use the sqlall predicate of manage.py to see the exact SQL that will be executed in order to generate the database.
Obviously django needs database tables for its basic functionality (contrib.apps).
Sure, you don't have to use them, but generally you want to use a least contrib.auth and some other bundled apps:
Each of these applications makes use
of at least one database table,
though, so we need to create the
tables in the database before we can
use them.
I any case you can't and shouldn't compare it to ugly html code generated by dreamweaver or word.
On a more abstract level:
One of key concepts of a web framework (following the mvc pattern) is that you define models which are "translated" (mapped) by the framework into database tables.
A model is the single, definitive
source of data about your data. It
contains the essential fields and
behaviors of the data you’re storing.
Generally, each model maps to a single
database table.
If you want to create the whole database scheme by hand you totally missed the point of using a web framework. In most cases you simply don't need to write sql manually. You define your classes and then you can query your objects using the builtin orm.
So in my Django project I have a few different apps, each with their own Models, Views, Templates, etc. What is a good way (the "Django" way) to have these Apps communicate?
A specific example would be a Meetings App which has a model for Meetings, and I have a Home App in which I want to display top 5 Meetings on the home page.
Should the Home App's View just query the Meetings App's Model?
It feels like that is crossing some line and there might be a more de-coupled way to do things like this in Django.
At some point your apps will have to couple in order to get any work done. You can't get around that.
To achieve decoupling as much as possible,
You need to have a Project specific app, that does all the hooking up things between each other.
Using signals from models to create new models in a decoupled apps helps. But doing too much of this, is foolish.
Should the Home App's View just query the Meetings App's Model?
Yep, that's how it's done. If you really want to decouple things, you could make your Home app use generic foreign keys, and some sort of generic template system, but there's not really a good reason to, unless you have grand plans for your home app being pluggable and working with a bunch of other different Django apps.
Writing tightly coupled Django apps is really easy, and writing decoupled Django apps is really hard. Don't decouple unless you have a reason to, and you'll save yourself a lot of work (and happiness!).
If it were me, I would make a template tag in your meeting app that produces the desired output and include that template tag in the home app's template.
That way you are only coupling them in the View portion of the MVC and makes it easier to maintain if you change your models in the meeting app.
For your specific example, I would use a Django templatetag.
Having a templatetag "display_top_meetings" in your Meetings app, and calling it with {{ display_top_meetings 5 }} from your index template, loading it first.
You can read more about templatetags here:
Django Official documentation about TemplateTags
B-List's article on writting 'better template tags'
I hope this help!
yes. I think thats a design feature. All models share a backend, so you'd have to do extra work to have two models with the same name in different apps.
Projects should not share Models