How does docker work and is it needed for web applications?

Question

Web development

I read about dockers, and some things are not clear.
Actually, the questions are:
1. If the container contains a web server, a database, then when writing the second application and launching it, will two web servers spin in the system?
2. How justified is the use of a docker, for example, when writing a web application in python?
3. If the host system is Windows, then to work with docker do you need to run a virtual machine with Linux and deploy docker on it?

Answer 1

1. If the container contains a web server, a database, then when writing the second application and launching it, will two web servers spin in the system?

Yes. But nothing prevents you from using one web server in front, and serving it with two containers with web applications.

2. How justified is the use of a docker, for example, when writing a web application in python?

One environment is on the server and on the developer's workstation.
Excellent integration into CI/CD in practice.
There is no need to clog the developer's machine with a bunch of installed databases of different versions, add. software and more.
Ease of deployment and more.
So fair enough...

3. If the host system is Windows, then to work with docker do you need to run a virtual machine with Linux and deploy docker on it?

Docker is also available for windows

Answer 2

If the container contains a web server, database

First, it is wrong to shove both the web server and the database into one container. Secondly, you should not shove the database into the container at all .

How justified is the use of docker, for example, when writing a web application in python?

In my opinion, only when it is supposed to operate this application in an automatically scalable environment with dozens of nodes. If you have one VPS, then containers are an overkill. And for the rest, Python has its own virtualization tools, which are quite enough.

Answer 3

not needed at all, this is an extra layer
of docker is convenient for admins so that they don’t install it with their hands, but simply pulled the image and that’s it.