Django handles the incoming requests with first in first out (Queue) principle. The Web Server opens one or more programs in parallel. The web server will send requests to a free process. Most of the  databases supported by django support concurrency, so there is no problem with having different processes handling the same app. Multiline logs written in the log file will take a hit due to race conditions.

No, Django runs as a single threaded application but with the servers used to run the Django application we can configure to use multi processes. But development serve is single threaded.

Servers such as Apache/mod_wsgi, gunicorn, or uwsgi can be configured to use multi processes

1. Views is a Python function that takes a web request and returns a web response. The view itself contains whatever arbitrary logic is necessary to return that response.

2. ViewSets help speed up the implementation of your API. Using ViewSet you don't have to create separate views for different actions you might want to take on a type of object. It removes the need to write a lot of boiler plate code.

3. Django has a number of mixins that provide more discrete functionality. Template rendering, for instance, is encapsulated in the <a href="https://docs.djangoproject.com/en/4.0/ref/class-based-views/mixins-simple/#django.views.generic.base.TemplateResponseMixin" target="_blank" style="color:#0057FF;">TemplateResponseMixin</a>

1. By implementing proper Authentication system

2. Configure API throttling by configuring DEFAULT_THROTTLE_CLASSES and DEFAULT_THROTTLE_RATES settings

1. Keep up with top 10 OWASP list of vulnerabilities.

2. Use ORM to avoid SQL injection attacks.

3. Use API throttling to avoid DOS attack.

4. Configure ALLOWED_HOSTS for proper header validation.

5. Enforce SSL/HTTP so that  the web server in order to encrypt all traffic between the site and browser.

1. Middleware is a framework of hooks into Django’s request/response processing. It’s a light, low-level “plugin” system for globally altering Django’s input or output.

2. Django uses middlewares during request and response processing

3. The order of middlewares looped through request processing will be top to bottom and during response processing it will be bottom to top

1. The ModelSerializer class provides a shortcut that lets you automatically create a Serializer class with fields that correspond to the Model fields.

2. Relational fields are used to represent model relationships. They can be applied to ForeignKey, ManyToManyField and OneToOneField relationships, as well as to reverse relationships, and custom relationships such as GenericForeignKey.

3. The HyperlinkedModelSerializer class is similar to the ModelSerializer class except that it uses hyperlinks to represent relationships, rather than primary keys.

1. By using Ofair option if worker processes to prioritize the celery tasks by disabling the prefetch behavior which manages computation time during heavy I/O operation.

2. By using autoscale option to increase worker processes automatically based on the total number of messages in queue.

3. Scaling horizontally by increasing the computation power or adding more machines.

Pickling a  queryset will force all the results to be loaded into memory prior to pickling. Pickling is usually used as a precursor to caching and when the cached queryset is reloaded, you want the results to already be present and ready for use.