check (within smart contract) if an account is a proxy

Question

How can I verify within a smart contract that an account is a proxy? I know that there is a function is_account, which verifies that a name is an existing account. Is there a way to check if an account is a proxy? Such as a function like is_proxy?

Answer 1

There's no provided is_proxy method, but proxy information is stored in multi_index in eosio account, you can query that from your contract. The next code block is an example of is_proxy implementation.

/**
 * @file proxy.hpp
 */
#pragma once

#include <eosio/eosio.hpp>
#include <eosio/asset.hpp>

namespace eosio {

   constexpr name system_account{"eosio"_n};

   struct voter_info {
      name                owner;
      name                proxy;
      std::vector<name>   producers;
      int64_t             staked = 0;
      double              last_vote_weight = 0;
      double              proxied_vote_weight= 0;
      bool                is_proxy = 0;
      uint32_t            flags1 = 0;
      uint32_t            reserved2 = 0;
      eosio::asset        reserved3;

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

      EOSLIB_SERIALIZE( voter_info, (owner)(proxy)(producers)(staked)(last_vote_weight)(proxied_vote_weight)(is_proxy)(flags1)(reserved2)(reserved3) )
   };

   typedef eosio::multi_index< "voters"_n, voter_info >  voters_table;

   bool is_proxy(name name) {
      voters_table _voters(system_account, system_account.value);

      auto it = _voters.find(name.value);
      return it != _voters.end() && it->is_proxy;
   }

} /// namespace eosio