graph/db: version reject cache for policies

Make the reject cache version-aware so v1 and v2 policy state can be
cached independently per channel ID.  Add helpers to store v1 timestamps
or v2 block heights and thread the versioned cache key through KV/SQL
store cache accesses.

graph/db/reject_cache_test.go

@@ -3,6 +3,8 @@ package graphdb
 import (
 	"reflect"
 	"testing"
+
+	"github.com/lightningnetwork/lnd/lnwire"
 )
 
 // TestRejectCache checks the behavior of the rejectCache with respect to insertion,
@@ -15,14 +17,14 @@ func TestRejectCache(t *testing.T) {
 
 	// As a sanity check, assert that querying the empty cache does not
 	// return an entry.
-	_, ok := c.get(0)
+	_, ok := c.get(lnwire.GossipVersion1, 0)
 	if ok {
 		t.Fatalf("reject cache should be empty")
 	}
 
 	// Now, fill up the cache entirely.
 	for i := uint64(0); i < cacheSize; i++ {
-		c.insert(i, entryForInt(i))
+		c.insert(lnwire.GossipVersion1, i, entryForInt(i))
 	}
 
 	// Assert that the cache has all of the entries just inserted, since no
@@ -30,7 +32,10 @@ func TestRejectCache(t *testing.T) {
 	assertHasEntries(t, c, 0, cacheSize)
 
 	// Now, insert a new element that causes the cache to evict an element.
-	c.insert(cacheSize, entryForInt(cacheSize))
+	c.insert(
+		lnwire.GossipVersion1, cacheSize,
+		entryForInt(cacheSize),
+	)
 
 	// Assert that the cache has this last entry, as the cache should evict
 	// some prior element and not the newly inserted one.
@@ -40,7 +45,7 @@ func TestRejectCache(t *testing.T) {
 	// elements.
 	evicted := make(map[uint64]struct{})
 	for i := uint64(0); i < cacheSize+1; i++ {
-		_, ok := c.get(i)
+		_, ok := c.get(lnwire.GossipVersion1, i)
 		if !ok {
 			evicted[i] = struct{}{}
 		}
@@ -54,9 +59,9 @@ func TestRejectCache(t *testing.T) {
 
 	// Remove the highest item which initially caused the eviction and
 	// reinsert the element that was evicted prior.
-	c.remove(cacheSize)
+	c.remove(lnwire.GossipVersion1, cacheSize)
 	for i := range evicted {
-		c.insert(i, entryForInt(i))
+		c.insert(lnwire.GossipVersion1, i, entryForInt(i))
 	}
 
 	// Since the removal created an extra slot, the last insertion should
@@ -69,7 +74,7 @@ func TestRejectCache(t *testing.T) {
 	// happening on inserts for existing cache items, we expect this to fail
 	// with high probability.
 	for i := uint64(0); i < cacheSize; i++ {
-		c.insert(i, entryForInt(i))
+		c.insert(lnwire.GossipVersion1, i, entryForInt(i))
 	}
 	assertHasEntries(t, c, 0, cacheSize)
 
@@ -82,7 +87,7 @@ func assertHasEntries(t *testing.T, c *rejectCache, start, end uint64) {
 	t.Helper()
 
 	for i := start; i < end; i++ {
-		entry, ok := c.get(i)
+		entry, ok := c.get(lnwire.GossipVersion1, i)
 		if !ok {
 			t.Fatalf("reject cache should contain chan %d", i)
 		}