providerQueryManager: when max == 0 in FindProvidersAsync, use maxProviders option.

Author: hsanjuan

bitswap/client/internal/session/session.go

@@ -410,9 +410,7 @@ func (s *Session) findMorePeers(ctx context.Context, c cid.Cid) {
 	go func(k cid.Cid) {
 		ctx, span := internal.StartSpan(ctx, "Session.FindMorePeers")
 		defer span.End()
-		// Max is set to -1. This means "use the default limit" in the
-		// provider query manager.
-		for p := range s.providerFinder.FindProvidersAsync(ctx, k, -1) {
+		for p := range s.providerFinder.FindProvidersAsync(ctx, k, 0) {
 			// When a provider indicates that it has a cid, it's equivalent to
 			// the providing peer sending a HAVE
 			span.AddEvent("FoundPeer")

routing/providerquerymanager/providerquerymanager.go

@@ -116,7 +116,9 @@ func WithMaxInProcessRequests(count int) Option {
 	}
 }
 
-// WithMaxProviders is the maximum number of providers that will be looked up per query
+// WithMaxProviders is the maximum number of providers that will be looked up
+// per query.  We only return providers that we can connect to. Defaults to 0,
+// which means unbounded.
 func WithMaxProviders(count int) Option {
 	return func(mgr *ProviderQueryManager) error {
 		mgr.maxProviders = count
@@ -168,11 +170,10 @@ func (pqm *ProviderQueryManager) setFindProviderTimeout(findProviderTimeout time
 
 // FindProvidersAsync finds providers for the given block. The max parameter
 // controls how many will be returned at most. For a provider to be returned,
-// we must have successfully connected to it. Setting max to -1 will use the
-// configured MaxProviders. Setting max to 0 will return an unbounded number
-// of providers.
+// we must have successfully connected to it. Setting max to 0 will use the
+// configured MaxProviders which defaults to 0 (unbounded).
 func (pqm *ProviderQueryManager) FindProvidersAsync(sessionCtx context.Context, k cid.Cid, max int) <-chan peer.AddrInfo {
-	if max < 0 {
+	if max == 0 {
 		max = pqm.maxProviders
 	}
 

routing/providerquerymanager/providerquerymanager_test.go

@@ -400,7 +400,7 @@ func TestLimitedProviders(t *testing.T) {
 	providerQueryManager.setFindProviderTimeout(100 * time.Millisecond)
 	keys := random.Cids(1)
 
-	providersChan := providerQueryManager.FindProvidersAsync(ctx, keys[0], -1)
+	providersChan := providerQueryManager.FindProvidersAsync(ctx, keys[0], 0)
 	total := 0
 	for range providersChan {
 		total++