From 9b104183122426e131669b007af9afff4727b70a Mon Sep 17 00:00:00 2001
From: Guillaume Ballet <gballet@gmail.com>
Date: Tue, 16 Jul 2019 13:34:20 +0200
Subject: [PATCH] cmd/geth: let retesteth increase the payload size

---
 cmd/geth/retesteth.go |  5 +++++
 rpc/http.go           | 21 +++++++++++++++------
 2 files changed, 20 insertions(+), 6 deletions(-)

diff --git a/cmd/geth/retesteth.go b/cmd/geth/retesteth.go
index 0615f446fc..4663c04c52 100644
--- a/cmd/geth/retesteth.go
+++ b/cmd/geth/retesteth.go
@@ -68,6 +68,7 @@ var (
 )
 
 type RetestethTestAPI interface {
+	SetRPCPayloadSize(ctx context.Context, size int) (int, error)
 	SetChainParams(ctx context.Context, chainParams ChainParams) (bool, error)
 	MineBlocks(ctx context.Context, number uint64) (bool, error)
 	ModifyTimestamp(ctx context.Context, interval uint64) (bool, error)
@@ -271,6 +272,10 @@ func (e *NoRewardEngine) Close() error {
 	return e.inner.Close()
 }
 
+func (api *RetestethAPI) SetRPCPayloadSize(ctx context.Context, size int) (int, error) {
+	return rpc.SetMaxRequestContentLength(size)
+}
+
 func (api *RetestethAPI) SetChainParams(ctx context.Context, chainParams ChainParams) (bool, error) {
 	// Clean up
 	if api.blockchain != nil {
diff --git a/rpc/http.go b/rpc/http.go
index 518b3b874f..baa844d4fa 100644
--- a/rpc/http.go
+++ b/rpc/http.go
@@ -35,14 +35,23 @@ import (
 	"github.com/rs/cors"
 )
 
-const (
-	maxRequestContentLength = 1024 * 512
-	contentType             = "application/json"
-)
+const contentType = "application/json"
+
+var maxRequestContentLength = 1024 * 512
 
 // https://www.jsonrpc.org/historical/json-rpc-over-http.html#id13
 var acceptedContentTypes = []string{contentType, "application/json-rpc", "application/jsonrequest"}
 
+// SetMaxRequestContentLength changes the maximum payload size to be accepted
+// by the RPC system. This is only to be changed for tests.
+func SetMaxRequestContentLength(length int) (int, error) {
+	if length < 0 {
+		return maxRequestContentLength, fmt.Errorf("Invalid RPC payload length %d", length)
+	}
+	maxRequestContentLength = length
+	return maxRequestContentLength, nil
+}
+
 type httpConn struct {
 	client    *http.Client
 	req       *http.Request
@@ -193,7 +202,7 @@ type httpServerConn struct {
 }
 
 func newHTTPServerConn(r *http.Request, w http.ResponseWriter) ServerCodec {
-	body := io.LimitReader(r.Body, maxRequestContentLength)
+	body := io.LimitReader(r.Body, int64(maxRequestContentLength))
 	conn := &httpServerConn{Reader: body, Writer: w, r: r}
 	return NewJSONCodec(conn)
 }
@@ -275,7 +284,7 @@ func validateRequest(r *http.Request) (int, error) {
 	if r.Method == http.MethodPut || r.Method == http.MethodDelete {
 		return http.StatusMethodNotAllowed, errors.New("method not allowed")
 	}
-	if r.ContentLength > maxRequestContentLength {
+	if r.ContentLength > int64(maxRequestContentLength) {
 		err := fmt.Errorf("content length too large (%d>%d)", r.ContentLength, maxRequestContentLength)
 		return http.StatusRequestEntityTooLarge, err
 	}