channeldb: add waiting proof storage

In this commit boltdb persistent storage have been added, which allow
as to not loose announcement proofs inside gossiper subsystem.

channeldb/waitingproof_test.go

@@ -0,0 +1,57 @@
+package channeldb
+
+import (
+	"testing"
+
+	"reflect"
+
+	"github.com/go-errors/errors"
+	"github.com/lightningnetwork/lnd/lnwire"
+)
+
+// TestWaitingProofStore tests add/get/remove functions of the waiting proof
+// storage.
+func TestWaitingProofStore(t *testing.T) {
+	db, cleanup, err := makeTestDB()
+	if err != nil {
+
+	}
+	defer cleanup()
+
+	proof1 := NewWaitingProof(true, &lnwire.AnnounceSignatures{
+		NodeSignature:    testSig,
+		BitcoinSignature: testSig,
+	})
+
+	store, err := NewWaitingProofStore(db)
+	if err != nil {
+		t.Fatalf("unable to create the waiting proofs storage: %v",
+			err)
+	}
+
+	if err := store.Add(proof1); err != nil {
+		t.Fatalf("unable add proof to storage: %v", err)
+	}
+
+	proof2, err := store.Get(proof1.Key())
+	if err != nil {
+		t.Fatalf("unable retrieve proof from storage: %v", err)
+	}
+	if !reflect.DeepEqual(proof1, proof2) {
+		t.Fatal("wrong proof retrieved")
+	}
+
+	if _, err := store.Get(proof1.OppositeKey()); err != ErrWaitingProofNotFound {
+		t.Fatalf("proof shouldn't be found: %v", err)
+	}
+
+	if err := store.Remove(proof1.Key()); err != nil {
+		t.Fatalf("unable remove proof from storage: %v", err)
+	}
+
+	if err := store.ForAll(func(proof *WaitingProof) error {
+		return errors.New("storage should be empty")
+	}); err != nil && err != ErrWaitingProofNotFound {
+		t.Fatal(err)
+	}
+}