From d52362a106a59fd9c6e8dfb243a2cd204ef7c470 Mon Sep 17 00:00:00 2001
From: Neil Alexander <neilalexander@users.noreply.github.com>
Date: Fri, 16 Oct 2020 13:26:04 +0100
Subject: [PATCH] Take write lock for rate limit map

---
 clientapi/routing/rate_limiting.go | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/clientapi/routing/rate_limiting.go b/clientapi/routing/rate_limiting.go
index 16e3c0565..9bd09022c 100644
--- a/clientapi/routing/rate_limiting.go
+++ b/clientapi/routing/rate_limiting.go
@@ -73,8 +73,13 @@ func (l *rateLimits) rateLimit(req *http.Request) *util.JSONResponse {
 	// let's create one.
 	rateLimit, ok := l.limits[caller]
 	if !ok {
-		l.limits[caller] = make(chan struct{}, l.requestThreshold)
-		rateLimit = l.limits[caller]
+		rateLimit = make(chan struct{}, l.requestThreshold)
+
+		l.limitsMutex.RUnlock()
+		l.limitsMutex.Lock()
+		l.limits[caller] = rateLimit
+		l.limitsMutex.Unlock()
+		l.limitsMutex.RLock()
 	}
 
 	// Check if the user has got free resource slots for this request.