What can I read to deal with grafana?

Question

infographics

There is some data on visits of site users.
Each user has some unique identifier and the country from which he comes.
I want to display as a chart the number of unique users per month by country.

How can this be done and what should be read? I don't know which way to go.

The visit data is stored in mongo, but I don't want the dashboard to load the main database.

Are there any options for me, for example, to calculate all the metrics on the side of my application, so that they only need to be drawn in the graphana?
Which chart would be more visual?

I have never worked with data visualization before.

Answer 1

A typical process looks like this:
Telegraf (metrics collector) takes the necessary metrics and puts them in a time series database (InfluxDB), it has a lot of built-in plugins and good documentation. It can take nginx logs and send them to InfluxDB
InfluxDB is one of the time series databases (TSDB), integrates well with Telegraf, and is developed by one company. There is an open source option.
Then, using Grafana , you extract the necessary data from TSDB, group / filter and display it in one of the plugins.
Instead of Telegraph (if you get bored) you can write a custom collector of metrics and put them in influx. I wrote in python (purely out of interest), but before that everything was done through the Telegraph.
The question is quite general, so the answer is also without too much specificity.