graph/db: version cacheable iteration methods

Add gossip version parameters to ForEachNodeCacheable and
ForEachChannelCacheable in the Store interface and both implementations.

Thread the version through SQL helpers and update call sites/tests
accordingly.

graph/db/graph.go

@@ -163,19 +163,23 @@ func (c *ChannelGraph) populateCache(ctx context.Context) error {
 	log.Info("Populating in-memory channel graph, this might take a " +
 		"while...")
 
-	err := c.db.ForEachNodeCacheable(ctx, func(node route.Vertex,
-		features *lnwire.FeatureVector) error {
+	// TODO(elle): the cache should be populated with data from across
+	//  protocol versions.
+	err := c.db.ForEachNodeCacheable(
+		ctx, lnwire.GossipVersion1, func(node route.Vertex,
+			features *lnwire.FeatureVector) error {
 
-		c.graphCache.AddNodeFeatures(node, features)
+			c.graphCache.AddNodeFeatures(node, features)
 
-		return nil
-	}, func() {})
+			return nil
+		}, func() {},
+	)
 	if err != nil {
 		return err
 	}
 
 	err = c.db.ForEachChannelCacheable(
-		func(info *models.CachedEdgeInfo,
+		lnwire.GossipVersion1, func(info *models.CachedEdgeInfo,
 			policy1, policy2 *models.CachedEdgePolicy) error {
 
 			c.graphCache.AddChannel(info, policy1, policy2)
@@ -606,10 +610,10 @@ func (c *ChannelGraph) ForEachNode(ctx context.Context,
 
 // ForEachNodeCacheable iterates through all stored vertices/nodes in the graph.
 func (c *ChannelGraph) ForEachNodeCacheable(ctx context.Context,
-	cb func(route.Vertex, *lnwire.FeatureVector) error,
-	reset func()) error {
+	v lnwire.GossipVersion, cb func(route.Vertex,
+		*lnwire.FeatureVector) error, reset func()) error {
 
-	return c.db.ForEachNodeCacheable(ctx, cb, reset)
+	return c.db.ForEachNodeCacheable(ctx, v, cb, reset)
 }
 
 // NodeUpdatesInHorizon returns all known lightning nodes with updates in the
@@ -642,14 +646,6 @@ func (c *ChannelGraph) ForEachChannel(ctx context.Context,
 	return c.db.ForEachChannel(ctx, v, cb, reset)
 }
 
-// ForEachChannelCacheable iterates through all channel edges for the cache.
-func (c *ChannelGraph) ForEachChannelCacheable(cb func(*models.CachedEdgeInfo,
-	*models.CachedEdgePolicy, *models.CachedEdgePolicy) error,
-	reset func()) error {
-
-	return c.db.ForEachChannelCacheable(cb, reset)
-}
-
 // DisabledChannelIDs returns the channel ids of disabled channels.
 func (c *ChannelGraph) DisabledChannelIDs() ([]uint64, error) {
 	return c.db.DisabledChannelIDs()
@@ -923,6 +919,22 @@ func (c *VersionedGraph) ForEachChannel(ctx context.Context,
 	return c.db.ForEachChannel(ctx, c.v, cb, reset)
 }
 
+// ForEachNodeCacheable iterates through all stored vertices/nodes in the graph.
+func (c *VersionedGraph) ForEachNodeCacheable(ctx context.Context,
+	cb func(route.Vertex, *lnwire.FeatureVector) error,
+	reset func()) error {
+
+	return c.db.ForEachNodeCacheable(ctx, c.v, cb, reset)
+}
+
+// ForEachChannelCacheable iterates through all channel edges for the cache.
+func (c *VersionedGraph) ForEachChannelCacheable(
+	cb func(*models.CachedEdgeInfo, *models.CachedEdgePolicy,
+		*models.CachedEdgePolicy) error, reset func()) error {
+
+	return c.db.ForEachChannelCacheable(c.v, cb, reset)
+}
+
 // IsPublicNode determines whether the node is seen as public in the graph.
 func (c *VersionedGraph) IsPublicNode(pubKey [33]byte) (bool, error) {
 	return c.db.IsPublicNode(c.v, pubKey)