In my recent project there was a lot of data business logic, so I had to organize this code somehow. In this article I'll describe a few hints on how to it.
Mixins
Simple business logic functions should in models or managers. When there's a lot of them, the can be split in mixins.
# logic.py
class EventLogic(object):
def start(self):
if self.condition():
# ...
# models.py
class Event(models.Model, EventLogic):
name = models.CharField()
# ...Custom exceptions
For business logic errors you should declare custom exception classes. It's not fun to understand what this specific IntegrityError means.
Generic views
When all logic is in model and can throw, say, BusinessLogicException, we can write views like this:
from django.contrib import messages
def event_action(requets, event_id, action):
# event = get_object_or_404(...)
try:
getattr(event, action)(request.user)
except BusinessLogicException, e:
messages.warning(request, e.message)
return redirect(request.POST.get('next') or event)Subscribe for the news and updates
One of our recent projects includes the functionality of an inline code editor. This code editor needed to be highly extensible and have custom features. To address this, we chose Codemirror v6 due to its peculiar architecture - it is highly customizable, and all the additional features are provided into codemirror engine as Extension objects.
Now it's time to get acquainted with Elasticsearch. This NoSQL database is used to store logs, analyze information and - most importantly - search.
There are two most popular web frameworks in Python. There is the Django with lots of intelligent defaults and the Flask micro framework with complete freedom in the choice of modules. Let’s see, what django vs flask is in 2017.
When dealing with one of our projects (LookSMI media monitoring platform) we have to handle the huge volume of data – and its quantity is constantly growing. At the same time, we must run quick searches with smart rules. In this article I'll explain how we have achieved required performance.
In VIM there is a command for char search: f. After first use it can be repeated with ;. I like to navigate in line with it. You see that you need to go to bracket in a middle of a line - you press f( and one-two ; and you are there. There's no such command in Emacs, so I had to write my own. I've managed even to implement repetition with ;.
Learn how to use "OR" and "AND" queries efficiently in Django without using database models Q. Enhance your query-building skills. Dive in now.