From 93c782a83016ee7de83c0c4613dbf03fde8cd9f1 Mon Sep 17 00:00:00 2001
From: Kosala Hemachandra <kvhnuke@aol.com>
Date: Thu, 4 Apr 2019 22:49:14 -0700
Subject: [PATCH] add multiple gas estimation

---
 graphql/graphql.go | 14 ++++++++++++++
 graphql/schema.go  |  1 +
 2 files changed, 15 insertions(+)

diff --git a/graphql/graphql.go b/graphql/graphql.go
index b3bcbd8a43..5569a52b80 100644
--- a/graphql/graphql.go
+++ b/graphql/graphql.go
@@ -945,6 +945,20 @@ func (p *Pending) EstimateGas(ctx context.Context, args struct {
 	return ethapi.DoEstimateGas(ctx, p.backend, args.Data, rpc.PendingBlockNumber)
 }
 
+func (p *Pending) EstimateGases(ctx context.Context, args struct {
+	Data *[]ethapi.CallArgs
+}) (*[]hexutil.Uint64, error) {
+	ret := make([]hexutil.Uint64, 0, len(*args.Data))
+	for _, call := range *args.Data {
+		estimatedGas, err := ethapi.DoEstimateGas(ctx, p.backend, call, rpc.PendingBlockNumber)
+		if err != nil {
+			return &ret, nil
+		}
+		ret = append(ret, estimatedGas)
+	}
+	return &ret, nil
+}
+
 // Resolver is the top-level object in the GraphQL hierarchy.
 type Resolver struct {
 	backend *eth.EthAPIBackend
diff --git a/graphql/schema.go b/graphql/schema.go
index bd913d9aa6..a7c7d791ed 100644
--- a/graphql/schema.go
+++ b/graphql/schema.go
@@ -289,6 +289,7 @@ const schema string = `
       # EstimateGas estimates the amount of gas that will be required for
       # successful execution of a transaction for the pending state.
       estimateGas(data: CallData!): Long!
+      estimateGases(data: [CallData!]): [Long!]
     }
 
     type Query {