How to make a client-server application with authorization and guaranteed delivery of information?

Question

linux

Hello! It is necessary to implement the following functionality:
1. Sending data by the client to the server (text), after authorization (PostgreSQL account)
2. Writing data to the server in PostgreSQL and processing by a script (worker), generating a file.
3. Transfer the file from the server to the client in automatic mode (~100Kb)
Requirements:
1. Security
2. Reliability (stable operation and guaranteed delivery of information in both directions)
3. Scalability (in case of an increase in clients and their requests)
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Based on the task and requirements, it seems to me that RabbitMQ + python + psycopg2 should be used on the server. Can you tell me how to implement such a scheme in the most competent way?

Answer 1

I'll try to describe the requirements in more detail:
1. Security - the transfer of information is not plain text, but for example using SSL
2. Reliability - it is important that messages cannot be lost if the connection between the client and the server suddenly disappears (therefore, the choice fell on RabbitMQ, it seems to be copes with such cases)
3. Scalability - well, for example, there will be 10 clients, then 100 ... if you use RabbitMQ, the issue seems to be solved quite easily.
Well, I'm not entirely sure that you can reliably transfer a file using RabbitMQ . The question is most likely whether the right technologies are chosen for this task. Vague because this is the second application I'm writing (the first in python).