Django, FastAPI and DRF - django

I want to make a project, which uses Django as backend, PostgreSQL as database and FastAPI with Django REST Framework for REST.
Don't see any problems with making a project just with Django, DRF and Postgres, but face with difficulties when speak about FastAPI and DRF at the same time.
So there is no problem in connecting Postgres to Django, and there is no problem to make endpoints for DRF.
But how can I connect fastapi? Where to place endpoints and how to run all this stuff together?
In some examples I saw that FastAPI isntance is initiated in WSGI.py and then server runs from calling commands such like this:
uvicorn goatfish.wsgi:app
But i am not sure that it works like this when I mix more than only Django and FastAPI.
I want to use FastAPI for optical character recongnition and DRF for user registration, logins etc.
Are there any advices about making project with such a structure? Or maybe someone have a repository with such kind of project on github?
EDIT: Hope to see answers here, but for now I only see the solution in making classic Django + DRF app, then make FastAPI app with endpoints, run these apps on different ports and do some chain of actions:
From django app we load an image to form and when we submit this form we send POST request to FastAPI endpoint, which will run OCR process and then return JSON with recognized text and then will send this JSON to the Django Callback endpoint, which will process it and save to the database.
What do you think about such thing?

I think, you may:
Mix of fastapi+django. But this is only for replace DRF and use fastapi as rest framework.
Microservices. You may to run Django on one port, fastapi - another. And both may to use one shared database.
Mircoservices. All from point 2, but some api tasks (for example sign-in/sign-up) on Django and another - on fastapi.

As an alterantive you could use django ninja.
It uses similar concepts as FastAPI (Routes, Pydandantic Model Validation, Async Support) but is an Django app.
Which of course is more the monolithic approach but still valid.

Well, so after few days of thinking about I decided, that there is no sense in a question which I asked :)
Here we should talk about microservice architecture, where such kind of problem just doesn't exist. All we need is to make as much services as we need in our project using any framework (Django, FastAPI, Flask, Ruby etc.) and make connections between them.
As example I can run my main Django server on port 8000, my FastAPI server on port 5000 and my DRF service on port 6000. And then I can just do whatever I want from my main Django server making requests to endpoints of FastAPI and DRF.
So that's very simple example, now I'm diving deeper into microservice architecturing, but that's definitely what I need.

Related

How to use django-ddp

I'm using django as backend. While reading stuff about meteor, i found django-ddp.
I searched a lot, but I didn't get what django-ddp is for.
I understood that you can use it to connect meteor to your django backend, but what is the use case?
How does the client connect to django and/or meteor? Does meteor have to run on the same server? How are the http requests handled?
Maybe a tiny example would help me to get this.
For me important: Can i use this to combine benefits of django and meteor?
Django DDP provides a Meteor compatible, realtime, latency compensated backend framework for Django (Python) models. It can also serve your Meteor frontend code (HTML/JS/CSS/...) allowing you to avoid using Meteor (and node.js) on the server, whilst serving regular Django views at the same time.
Django is a respected web framework with a powerful object relational mapper (ORM), with support for schema migrations included by default. Django DDP is efficient and secure, using gevent to handle HTTP requests and manage concurrency at the process level, and multiple processes (across multiple hosts) to allow scaling-out to serve many clients simultaneously. WebSockets are handled using gevent-websocket. Combining these aspects with the realtime, latency compensated benefits of Meteor does indeed give you the advantages of both (unless you prefer to run node.js on your backend servers).
If Django DDP is used to serve your Meteor app then the client (browser) will connect to Django DDP automatically. Otherwise, you can connect your Meteor app to Django DDP and use the Django DDP connection like this:
if(Meteor.isClient) {
Django = DDP.connect('http://ddp.example.com/');
Tasks = new Mongo.Collection('myapp.Tasks', {connection: Django});
Django.subscribe('Tasks', {
onReady: function(error, result) {
// Log each matching Task to the browser console in a table
console.table(Tasks.find().fetch());
}
});
}
If you're serving your Meteor app from Django DDP then drop the DDP.connect line and omit the second parameter to new Mongo.Collection.
You might find the Todos example app a useful place to start. It includes a full working example of how to write both the Meteor client app and the Django DDP server app.
Disclaimer: I'm the author of Django DDP - sorry if parts of my answer sound like marketing guff but I'm just trying to answer the first part of the question.

Running a meteor app as part of a wider django project

I'm currently working on a project which would require some realtime functionalities such as Multi-user chatrooms etc.
Ideally, I’m looking to have meteor run the chat application(on a different port) and mongodb act as message broker to the django back-end which would take care of user registration , management and everything 'non-realtime' related.
This would involve setting up a reverse-proxy which would redirect to a different port based on the url (please let me know if i'm wrong in this)
Would this be possible(or even advisable)? Another option would be to implement the same with tornado. but I have no experience with building tornado-based apps and rather do this with a framework I’m comfortable with.
Thanks,
You can have Django serve the Meteor front-end while providing access to its data using django-ddp, giving you some distinct advantages:
Continue to serve your existing Django project/apps.
No extra services or ports to manage.
Scale out by simply adding more front-end Python/Django servers (server to server IPC is done via the existing database connection).
Use django.contrib.auth user accounts in your Meteor app.
Familiar Python/Django code (no "callback" style such as with Tornado).
Use time-tested, trusted relational databases.
Use Django migrations to effectively manage schema changes.
There's a Gitter chat room where I can give you assistance if you need it.
DISCLAIMER: I'm the author of django-ddp.
A meteor application is more than capable of handling the user registration flow and many other things. Why not just build the application entirely in meteor? Your application sounds like a perfect candidate for meteor, with realtime interaction with your database at the core.
The other option would be to use swampdragon which adds realtime data binding within django. It allows for simple bi directional communication between the server and the client. Again, essential for a chat application. It nice and easy to get setup and running as well.
Are there any specific reasons to not implementing your application in one framework alone?

Apache/wsgi/django configuration

We have two django applications running on the same server that interact with an API that uses oauth. They function as expected, communicating with each other, when run under the django development server. However, when deployed using apache/wsgi they don't work together.
(To be more specific, one application is an instance of the Indivo server; the other one is a custom application that interacts with Indivo.)
What is the best way to trouble shoot this?
Make sure that the Django instances are working by themselves first. For example, one app could be started under Apache, and the other using ./manage.py runserver. Reverse which one is running using Apache and verify that all works as expected.
Use the Apache error logs to look for errors such as failed requests.
Since one of your apps appears to implement a web API, use something like the Google Chrome Postman App to exercise the site from a web browser.
Learn how to use the Django logging framework to log information about your apps as they execute.

Django app as REST-based service

According to the documentation, an app is a module which deals a well defined operation.
Is it correct to think about an app as a REST-based service? or is it mandatory to use some framework like piston or tastypie to create a RESTful web service around an app?
Generally, no. Django app is really just a python module, with some interfaces to django internals like models, urls, admin discovery etc.
To implement REST, you still have to manage network communications via views, and this is where you either write your own code or use the help of tastypie/piston/etc.
Please do have a look at django-rest-framework, I just stepped over from tastypie to this new framework, works great!
http://django-rest-framework.org/
Especially the class based views and the browsable api! and may other advantages (e..g. to upload images)
And to answer your question:
The rest-base service is an extra entry to your webapp.
I made some api's for some projects using the django-rest-framework, most project members were surprised they got a webapp as an extra, while it was actually the other way around. You make a django app (with views models and urls) and on top off that you make the api.

Accessing a django-piston REST API via a django view within the same project

I'm building a small web service. To showcase what the service can do I am going to build a lite-weight interface. I'm having a hard time figuring out how my REST API and regular Django views can play nicely together.
Here's my setup:
Using django-piston to build a simple CRUD REST web service.
Using Django views with httplib2 to GET/POST to/from that web service.
Both are being run from the same Django project (and thus same web server).
Right now I have simple read REST service working in the browser. But when I try to use httplib2 from the Django view the request just hangs.
My questions:
-Am I thinking about this the right way?
-Is there a better way to accomplish this?
-Should my REST web service be a different project (and web server) than my REST interface?
Any help would be greatly appreciated!
Generally, I'd demonstrate an API working via unit tests, rather than live views, but can see how that might not be what you need.
So (in line with akonsu's comment above) if you're experiencing this problem local dev, it's the single threaded devserver that's blocking the API from running while the view is executing.
Have you tried a multi-threaded version of the runserver? Like this one?