How srsRAN connect with Flexric?

[newt2105]

Hi everyone, I'm just done O-RAN NearRT-RIC and xApp (https://docs.srsran.com/projects/project/en/latest/tutorials/source/near-rt-ric/source/) and I want to create new xApp. But I'm not know how xApp collect data from E2 Node, I'm read some documents and understand that gNB connect with Near-RT Ric through E2 interface then Near-RT RIC send data to xApp.

Can someone show me the code that they do this or the protocol they do?
Thanks a lots.