How to get polygon vertex coordinates in OpenLayers?

Question

OpenStreetMap

There is a task: to receive the list of all objects in the chosen area. The selected area is the area selected dynamically by the user. Having received the coordinates of the vertices, I can extract the desired objects from the database by their coordinates.
You can, of course, draw arbitrary shapes by clicking with the cursor, while getting the coordinates by clicking is not difficult. But then another "problem" will appear - users will start clicking anywhere and building various shapes, which will complicate the task "by an order of magnitude".

Answer 1

https://openlayers.org/en/v4.6.5/examples/box-sele...