Python 3.+ resource parser with output from DB to GUI. How best to implement?

Question

Python

Guys, good day to all. I haven’t done parsing before, to be honest, but mostly I was developing on django + flask + frontend, so I don’t have enough knowledge to implement the task from scratch.
Task: write an html parser that brings all the data from the database to the GUI, but there are some features.
- there should be simple authentication, because the resource is private and only the user can retrieve the data
- the output will be on the GUI in a sortable table (pyQt does it out of the box like?) and a graph. The difference between the new and old prices should also be displayed.
- very deep html tree
- the database should be updated every day, and after that, the analysis of new added products with old ones should be carried out, and after displaying on the GUI in a sortable list
- the output of the site's products is done using pagination and ajax, so the parser should receive data, taking into account these features
Friends, how and what is easier to implement this task, based on the above data? Thank you very much for your help!

Answer 1

There are many options:
1. requests + lxml
2. scrapy
3. grab
But it's not clear where the data is to be robbed from, from a database or some kind of closed resource. The parser usually does not take any data from the database to the GUI, its task is to get onto some resource, get data from there, transform its structure and save it in the database, xml, csv, json ...
Why not just save it in csv, but as GUI to use Excel?