From 17ea6411a24bd76e9b0cd4c4cd8e886bb0863181 Mon Sep 17 00:00:00 2001
From: Roman Khimov <roman@nspcc.ru>
Date: Thu, 2 Jul 2020 16:00:07 +0300
Subject: [PATCH] rpc/client: ensure compatibility with preview2 C# node for
 invoke*

It won't work with proper cosigners and the client must be compatible both
with neo-go and C# node. See neo/neo-modules#260 also.
---
 pkg/rpc/client/rpc.go | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/pkg/rpc/client/rpc.go b/pkg/rpc/client/rpc.go
index f19fdd83e..f41bf38eb 100644
--- a/pkg/rpc/client/rpc.go
+++ b/pkg/rpc/client/rpc.go
@@ -369,6 +369,18 @@ func (c *Client) invokeSomething(method string, p request.RawParams, cosigners [
 		p.Values = append(p.Values, cosigners)
 	}
 	if err := c.performRequest(method, p, resp); err != nil {
+		// Retry with old-fashioned hashes (see neo/neo-modules#260).
+		if cosigners != nil {
+			var hashes = make([]util.Uint160, len(cosigners))
+			for i := range cosigners {
+				hashes[i] = cosigners[i].Account
+			}
+			p.Values[len(p.Values)-1] = hashes
+			err = c.performRequest(method, p, resp)
+			if err == nil {
+				return resp, nil
+			}
+		}
 		return nil, err
 	}
 	return resp, nil