#222: Add new request/response to check transaction validity in mempool

koinos/rpc/mempool/mempool_rpc.proto

@@ -44,12 +44,27 @@ message check_account_nonce_response {
    bool success = 1;
 }
 
+message check_transaction_eligibility_request {
+   bytes payer = 1 [(btype) = ADDRESS];
+   bytes payee = 2 [(btype) = ADDRESS];
+   bytes nonce = 3;
+   uint64 max_payer_rc = 4 [jstype = JS_STRING];
+   uint64 rc_limit = 5 [jstype = JS_STRING];
+
+   optional bytes block_id = 1000 [(btype) = BLOCK_ID];
+}
+
+message check_transaction_eligibility_response {
+   bool success = 1;
+}
+
 message mempool_request {
    oneof request {
       rpc.reserved_rpc reserved = 1;
       check_pending_account_resources_request check_pending_account_resources = 2;
       get_pending_transactions_request get_pending_transactions = 3;
       check_account_nonce_request check_account_nonce = 4;
+      check_transaction_eligibility_request check_transaction_eligibility = 5;
    }
 }
 
@@ -60,5 +75,6 @@ message mempool_response {
       check_pending_account_resources_response check_pending_account_resources = 3;
       get_pending_transactions_response get_pending_transactions = 4;
       check_account_nonce_response check_account_nonce = 5;
+      check_transaction_eligibility_response check_transaction_eligibility = 6;
    }
 }