graphdb: add test for cache invalidation

Author: Abdulkbk

graph/db/graph_sql_test.go

@@ -0,0 +1,75 @@
+//go:build test_db_postgres || test_db_sqlite
+
+package graphdb
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+// TestNodeIsPublicCacheInvalidation ensures that we invalidate correctly our
+// cache we use when determing if a node is public or not.
+func TestNodeIsPublicCacheInvalidation(t *testing.T) {
+	t.Parallel()
+	ctx := t.Context()
+
+	graph := MakeTestGraph(t)
+
+	node1 := createTestVertex(t)
+	node2 := createTestVertex(t)
+
+	require.NoError(t, graph.AddNode(ctx, node1))
+	require.NoError(t, graph.AddNode(ctx, node2))
+
+	edge, _ := createEdge(10, 0, 0, 0, node1, node2)
+	require.NoError(t, graph.AddChannelEdge(ctx, &edge))
+
+	// First IsPublic call should populate cache.
+	isPublic1, err := graph.IsPublicNode(node1.PubKeyBytes)
+	require.NoError(t, err)
+	require.True(t, isPublic1)
+
+	// Test invalidation scenarios:
+
+	// 1. DeleteChannelEdges:
+	// Above, the channel being public should be cached, but we expect that
+	// DeleteChannelEdge will invalidate the cache for both nodes else when
+	// we call IsPublic, we will hit the cache.
+	err = graph.DeleteChannelEdges(false, true, edge.ChannelID)
+	require.NoError(t, err)
+	isPublic1, err = graph.IsPublicNode(node1.PubKeyBytes)
+	require.NoError(t, err)
+	require.False(t, isPublic1)
+
+	isPublic2, err := graph.IsPublicNode(node2.PubKeyBytes)
+	require.NoError(t, err)
+	require.False(t, isPublic2)
+
+	// 2. AddChannelEdge:
+	// Now we know that the last `IsPublicNode` call above will cache our
+	// nodes with `isPublic` = false. But add a new channel edge should
+	// invalidate the cache such that when we call `IsPublic` it should
+	// return `True`.
+	edge2, _ := createEdge(10, 1, 0, 1, node1, node2)
+	require.NoError(t, graph.AddChannelEdge(ctx, &edge2))
+	isPublic1, err = graph.IsPublicNode(node1.PubKeyBytes)
+	require.NoError(t, err)
+	require.True(t, isPublic1)
+
+	isPublic2, err = graph.IsPublicNode(node2.PubKeyBytes)
+	require.NoError(t, err)
+	require.True(t, isPublic2)
+
+	// 3. DeleteNode:
+	// Again, the last two sets of `IsPublic` should have cached our nodes
+	// as `True`. Now we can delete a node and expect the next call to be
+	// False.
+	//
+	// NOTE: We don't get an error calling `IsPublicNode` because of how the
+	// SQL query is implemented to check for the existence of public nodes.
+	require.NoError(t, graph.DeleteNode(ctx, node1.PubKeyBytes))
+	isPublic1, err = graph.IsPublicNode(node1.PubKeyBytes)
+	require.NoError(t, err)
+	require.False(t, isPublic1)
+}