How to parse a value from this site?

Question

Parsing

It is required to periodically obtain the value of the water level in the river. The graph is on this site https://allrivers.info/gauge/iya-tulun , which refers to this one as a data source http://gis.vodinfo.ru . On the second site, there is only an informer code that gives a png with a graph. How can you get the desired value from any of these sites?

Answer 1

The data on the graph is obtained using a separate xhr request, which can be tracked through the browser in the developer tools on the Network tab (in Google Chrome). This query is what you need to recreate in order to get the data.