Getting account CPU usage in smart contract

Question

Is it possible to access the CPU usage of a given account from within a smart contract?

For eg. in a smart contract transfer notification, you call get_account_info(N(some_account_name)) which returns a struct object containing {cpu_used, cpu_available, net_used, net_available, ram_used} etc.

Answer 1

In order to access this information, you must create a struct as follows:

   struct [[eosio::table, eosio::contract("eosio.system")]] user_resources {
      name          owner;
      asset         net_weight;
      asset         cpu_weight;
      int64_t       ram_bytes = 0;

      uint64_t primary_key()const { return owner.value; }

      // explicit serialization macro is not necessary, used here only to improve compilation time
      EOSLIB_SERIALIZE( user_resources, (owner)(net_weight)(cpu_weight)(ram_bytes) )
   };
   typedef eosio::multi_index< "userres"_n, user_resources >      user_resources_table;

Then, in order to access a user's resources, you can do:

   user_resources_table  userres( _self, username.value );
   auto user = userres.find(username.value);
   print("User's NET EOS staked: ",user->net_weight,"\n");
   print("User's CPU EOS staked: ",user->_weight,"\n");
   print("User's RAM: ",user->ram_bytes,"\n");

Note: I haven't tested this code yet. Please edit appropriately if there is a typo or other mistake