It seems to be utilizing the OnlyAdminModule from here:
https://github.com/ElrondNetwork/elrond-wasm-rs/blob/master/elrond-wasm-modules/src/only_admin.rs
Might be clearer looking at the mandos test:
https://github.com/ElrondNetwork/elrond-wasm-rs/blob/master/contracts/feature-tests/use-module/mandos/use_module_only_admin.scen.json
After deployment the owner adds another wallet as admin (without giving up ownership) and then only the admin is able to call the only_admin_mod_endpoint
It seems to be utilizing the OnlyAdminModule from here: https://github.com/ElrondNetwork/elrond-wasm-rs/blob/master/elrond-wasm-modules/src/only_admin.rs Might be clearer looking at the mandos test: https://github.com/ElrondNetwork/elrond-wasm-rs/blob/master/contracts/feature-tests/use-module/mandos/use_module_only_admin.scen.json After deployment the owner adds another wallet as admin (without giving up ownership) and then only the admin is able to call the only_admin_mod_endpoint