From 0ad13d35a74565b148a5aff47e54e50700527698 Mon Sep 17 00:00:00 2001
From: dirkmc <dirkmdev@gmail.com>
Date: Fri, 4 Aug 2023 14:41:57 +0200
Subject: [PATCH] fix: startup with disabled index provider (#1604)

---
 node/modules/graphsync.go                   | 6 ++++--
 retrievalmarket/server/gsunpaidretrieval.go | 2 +-
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/node/modules/graphsync.go b/node/modules/graphsync.go
index cd6695742..8ecb75b8e 100644
--- a/node/modules/graphsync.go
+++ b/node/modules/graphsync.go
@@ -69,8 +69,10 @@ func (p *LinkSystemProv) LinkSys() *ipld.LinkSystem {
 }
 
 func SetLinkSystem(proxy *LinkSystemProv, prov provider.Interface) {
-	e := prov.(*engine.Engine)
-	proxy.LinkSystem = e.LinkSystem()
+	e, ok := prov.(*engine.Engine)
+	if ok {
+		proxy.LinkSystem = e.LinkSystem()
+	}
 }
 
 // RetrievalGraphsync creates a graphsync instance used to serve retrievals.
diff --git a/retrievalmarket/server/gsunpaidretrieval.go b/retrievalmarket/server/gsunpaidretrieval.go
index 2f97a6289..6740a3d2d 100644
--- a/retrievalmarket/server/gsunpaidretrieval.go
+++ b/retrievalmarket/server/gsunpaidretrieval.go
@@ -120,7 +120,7 @@ func (g *GraphsyncUnpaidRetrieval) Start(ctx context.Context) error {
 	g.ctx = ctx
 	g.validator.ctx = ctx
 
-	if g.linkSystem != nil {
+	if g.linkSystem != nil && g.linkSystem.LinkSys() != nil {
 		// The index provider uses graphsync to fetch advertisements.
 		// We need to tell graphsync to use a different IPLD Link System to provide
 		// the advertisements (instead of using the blockstore).