adding api to query vote objects by id

libraries/app/api.cpp

@@ -417,6 +417,44 @@ namespace graphene { namespace app {
           return *itr;
        return {};
     }
+    vector<variant> database_api::lookup_vote_ids( const vector<vote_id_type>& votes )const
+    {
+       FC_ASSERT( votes.size() < 100, "Only 100 votes can be queried at a time" );
+
+       const auto& witness_idx = _db.get_index_type<witness_index>().indices().get<by_vote_id>();
+       const auto& committee_idx = _db.get_index_type<committee_member_index>().indices().get<by_vote_id>();
+
+       vector<variant> result;
+       result.reserve( votes.size() );
+       for( auto id : votes )
+       {
+          switch( id.type() )
+          {
+             case vote_id_type::committee:
+             {
+                auto itr = committee_idx.find( id );
+                if( itr != committee_idx.end() )
+                   result.emplace_back( variant( *itr ) );
+                else
+                   result.emplace_back( variant() );
+                break;
+             }
+             case vote_id_type::witness:
+             {
+                auto itr = witness_idx.find( id );
+                if( itr != witness_idx.end() )
+                   result.emplace_back( variant( *itr ) );
+                else
+                   result.emplace_back( variant() );
+                break;
+             }
+             case vote_id_type::worker:
+                break;
+             case vote_id_type::VOTE_TYPE_COUNT: break; // supress unused enum value warnings
+          }
+       }
+       return result;
+    }
 
     uint64_t database_api::get_witness_count()const
     {

libraries/app/include/graphene/app/api.hpp

@@ -222,6 +222,16 @@ namespace graphene { namespace app {
           */
          fc::optional<witness_object> get_witness_by_account(account_id_type account)const;
 
+         /**
+          *  @brief Given a set of votes, return the objects they are voting for.  
+          *
+          *  This will be a mixture of committee_member_object, witness_objects, and worker_objects 
+          *
+          *  The results will be in the same order as the votes.  Null will be returned for
+          *  any vote ids that are not found.
+          */
+         vector<variant> lookup_vote_ids( const vector<vote_id_type>& votes )const;
+
          /**
           * @brief Get the total number of witnesses registered with the blockchain
           */
@@ -558,6 +568,7 @@ FC_API(graphene::app::database_api,
        (get_witnesses)
        (get_committee_members)
        (get_witness_by_account)
+       (lookup_vote_ids)
        (get_witness_count)
        (lookup_witness_accounts)
        (lookup_committee_member_accounts)

libraries/chain/include/graphene/chain/committee_member_object.hpp

@@ -48,6 +48,7 @@ namespace graphene { namespace chain {
    };
 
    struct by_account;
+   struct by_vote_id;
    using committee_member_multi_index_type = multi_index_container<
       committee_member_object,
       indexed_by<
@@ -56,6 +57,9 @@ namespace graphene { namespace chain {
          >,
          hashed_unique< tag<by_account>,
             member<committee_member_object, account_id_type, &committee_member_object::committee_member_account>
+         >,
+         hashed_unique< tag<by_vote_id>,
+            member<committee_member_object, vote_id_type, &committee_member_object::vote_id>
          >
       >
    >;

libraries/chain/include/graphene/chain/protocol/vote.hpp

@@ -52,6 +52,7 @@ struct vote_id_type
    /// Lower 8 bits are type; upper 24 bits are instance
    uint32_t content;
 
+   friend size_t hash_value( vote_id_type v ) { return std::hash<uint32_t>()(v.content); }
    enum vote_type
    {
       committee,

libraries/chain/include/graphene/chain/witness_object.hpp

@@ -43,6 +43,7 @@ namespace graphene { namespace chain {
    };
 
    struct by_account;
+   struct by_vote_id;
    using witness_multi_index_type = multi_index_container<
       witness_object,
       indexed_by<
@@ -51,6 +52,9 @@ namespace graphene { namespace chain {
          >,
          hashed_unique< tag<by_account>,
             member<witness_object, account_id_type, &witness_object::witness_account>
+         >,
+         hashed_unique< tag<by_vote_id>,
+            member<witness_object, vote_id_type, &witness_object::vote_id>
          >
       >
    >;