open-vault/physical/raft/snapshot_test.go

959 lines
21 KiB
Go

package raft
import (
"bytes"
"context"
"fmt"
"hash/crc64"
"io"
"io/ioutil"
"net/http/httptest"
"os"
"path/filepath"
"reflect"
"runtime"
"testing"
"time"
hclog "github.com/hashicorp/go-hclog"
"github.com/hashicorp/raft"
"github.com/hashicorp/vault/sdk/logical"
"github.com/hashicorp/vault/sdk/physical"
"github.com/hashicorp/vault/sdk/plugin/pb"
)
type idAddr struct {
id string
}
func (a *idAddr) Network() string { return "inmem" }
func (a *idAddr) String() string { return a.id }
func addPeer(t *testing.T, leader, follower *RaftBackend) {
t.Helper()
if err := leader.AddPeer(context.Background(), follower.NodeID(), follower.NodeID()); err != nil {
t.Fatal(err)
}
peers, err := leader.Peers(context.Background())
if err != nil {
t.Fatal(err)
}
err = follower.Bootstrap(peers)
if err != nil {
t.Fatal(err)
}
err = follower.SetupCluster(context.Background(), SetupOpts{})
if err != nil {
t.Fatal(err)
}
leader.raftTransport.(*raft.InmemTransport).Connect(raft.ServerAddress(follower.NodeID()), follower.raftTransport)
follower.raftTransport.(*raft.InmemTransport).Connect(raft.ServerAddress(leader.NodeID()), leader.raftTransport)
}
func TestRaft_Snapshot_Loading(t *testing.T) {
raft, dir := getRaft(t, true, false)
defer os.RemoveAll(dir)
// Write some data
for i := 0; i < 1000; i++ {
err := raft.Put(context.Background(), &physical.Entry{
Key: fmt.Sprintf("key-%d", i),
Value: []byte(fmt.Sprintf("value-%d", i)),
})
if err != nil {
t.Fatal(err)
}
}
readCloser, writeCloser := io.Pipe()
metaReadCloser, metaWriteCloser := io.Pipe()
go func() {
raft.fsm.writeTo(context.Background(), metaWriteCloser, writeCloser)
}()
// Create a CRC64 hash
stateHash := crc64.New(crc64.MakeTable(crc64.ECMA))
// Compute the hash
size1, err := io.Copy(stateHash, metaReadCloser)
if err != nil {
t.Fatal(err)
}
computed1 := stateHash.Sum(nil)
// Create a CRC64 hash
stateHash = crc64.New(crc64.MakeTable(crc64.ECMA))
// Compute the hash
size2, err := io.Copy(stateHash, readCloser)
if err != nil {
t.Fatal(err)
}
computed2 := stateHash.Sum(nil)
if size1 != size2 {
t.Fatal("sizes did not match")
}
if !bytes.Equal(computed1, computed2) {
t.Fatal("hashes did not match")
}
snapFuture := raft.raft.Snapshot()
if err := snapFuture.Error(); err != nil {
t.Fatal(err)
}
meta, reader, err := snapFuture.Open()
if err != nil {
t.Fatal(err)
}
if meta.Size != size1 {
t.Fatal("meta size did not match expected")
}
// Create a CRC64 hash
stateHash = crc64.New(crc64.MakeTable(crc64.ECMA))
// Compute the hash
size3, err := io.Copy(stateHash, reader)
if err != nil {
t.Fatal(err)
}
computed3 := stateHash.Sum(nil)
if size1 != size3 {
t.Fatal("sizes did not match")
}
if !bytes.Equal(computed1, computed3) {
t.Fatal("hashes did not match")
}
}
func TestRaft_Snapshot_Index(t *testing.T) {
raft, dir := getRaft(t, true, false)
defer os.RemoveAll(dir)
err := raft.Put(context.Background(), &physical.Entry{
Key: "key",
Value: []byte("value"),
})
if err != nil {
t.Fatal(err)
}
// Get index
index, _ := raft.fsm.LatestState()
if index.Term != 2 {
t.Fatalf("unexpected term, got %d expected 2", index.Term)
}
if index.Index != 3 {
t.Fatalf("unexpected index, got %d expected 3", index.Term)
}
// Write some data
for i := 0; i < 100; i++ {
err := raft.Put(context.Background(), &physical.Entry{
Key: fmt.Sprintf("key-%d", i),
Value: []byte(fmt.Sprintf("value-%d", i)),
})
if err != nil {
t.Fatal(err)
}
}
// Get index
index, _ = raft.fsm.LatestState()
if index.Term != 2 {
t.Fatalf("unexpected term, got %d expected 2", index.Term)
}
if index.Index != 103 {
t.Fatalf("unexpected index, got %d expected 103", index.Term)
}
// Take a snapshot
snapFuture := raft.raft.Snapshot()
if err := snapFuture.Error(); err != nil {
t.Fatal(err)
}
meta, reader, err := snapFuture.Open()
if err != nil {
t.Fatal(err)
}
io.Copy(ioutil.Discard, reader)
if meta.Index != index.Index {
t.Fatalf("indexes did not match, got %d expected %d", meta.Index, index.Index)
}
if meta.Term != index.Term {
t.Fatalf("term did not match, got %d expected %d", meta.Term, index.Term)
}
// Write some more data
for i := 0; i < 100; i++ {
err := raft.Put(context.Background(), &physical.Entry{
Key: fmt.Sprintf("key-%d", i),
Value: []byte(fmt.Sprintf("value-%d", i)),
})
if err != nil {
t.Fatal(err)
}
}
// Open the same snapshot again
meta, reader, err = raft.snapStore.Open(meta.ID)
if err != nil {
t.Fatal(err)
}
io.Copy(ioutil.Discard, reader)
// Make sure the meta data has updated to the new values
if meta.Index != 203 {
t.Fatalf("unexpected snapshot index %d", meta.Index)
}
if meta.Term != 2 {
t.Fatalf("unexpected snapshot term %d", meta.Term)
}
}
func TestRaft_Snapshot_Peers(t *testing.T) {
raft1, dir := getRaft(t, true, false)
raft2, dir2 := getRaft(t, false, false)
raft3, dir3 := getRaft(t, false, false)
defer os.RemoveAll(dir)
defer os.RemoveAll(dir2)
defer os.RemoveAll(dir3)
// Write some data
for i := 0; i < 1000; i++ {
err := raft1.Put(context.Background(), &physical.Entry{
Key: fmt.Sprintf("key-%d", i),
Value: []byte(fmt.Sprintf("value-%d", i)),
})
if err != nil {
t.Fatal(err)
}
}
// Force a snapshot
snapFuture := raft1.raft.Snapshot()
if err := snapFuture.Error(); err != nil {
t.Fatal(err)
}
commitIdx := raft1.CommittedIndex()
// Add raft2 to the cluster
addPeer(t, raft1, raft2)
ensureCommitApplied(t, commitIdx, raft2)
// Make sure the snapshot was applied correctly on the follower
if err := compareDBs(t, raft1.fsm.getDB(), raft2.fsm.getDB(), false); err != nil {
t.Fatal(err)
}
// Write some more data
for i := 1000; i < 2000; i++ {
err := raft1.Put(context.Background(), &physical.Entry{
Key: fmt.Sprintf("key-%d", i),
Value: []byte(fmt.Sprintf("value-%d", i)),
})
if err != nil {
t.Fatal(err)
}
}
snapFuture = raft1.raft.Snapshot()
if err := snapFuture.Error(); err != nil {
t.Fatal(err)
}
commitIdx = raft1.CommittedIndex()
// Add raft3 to the cluster
addPeer(t, raft1, raft3)
ensureCommitApplied(t, commitIdx, raft2)
ensureCommitApplied(t, commitIdx, raft3)
// Make sure all stores are the same
compareFSMs(t, raft1.fsm, raft2.fsm)
compareFSMs(t, raft1.fsm, raft3.fsm)
}
func ensureCommitApplied(t *testing.T, leaderCommitIdx uint64, backend *RaftBackend) {
t.Helper()
timeout := time.Now().Add(10 * time.Second)
for {
if time.Now().After(timeout) {
t.Fatal("timeout reached while verifying applied index on raft backend")
}
if backend.AppliedIndex() >= leaderCommitIdx {
break
}
time.Sleep(1 * time.Second)
}
}
func TestRaft_Snapshot_Restart(t *testing.T) {
raft1, dir := getRaft(t, true, false)
defer os.RemoveAll(dir)
raft2, dir2 := getRaft(t, false, false)
defer os.RemoveAll(dir2)
// Write some data
for i := 0; i < 100; i++ {
err := raft1.Put(context.Background(), &physical.Entry{
Key: fmt.Sprintf("key-%d", i),
Value: []byte(fmt.Sprintf("value-%d", i)),
})
if err != nil {
t.Fatal(err)
}
}
// Take a snapshot
snapFuture := raft1.raft.Snapshot()
if err := snapFuture.Error(); err != nil {
t.Fatal(err)
}
// Advance FSM's index past configuration change
raft1.Put(context.Background(), &physical.Entry{
Key: "key",
Value: []byte("value"),
})
// Add raft2 to the cluster
addPeer(t, raft1, raft2)
time.Sleep(2 * time.Second)
peers, err := raft2.Peers(context.Background())
if err != nil {
t.Fatal(err)
}
if len(peers) != 2 {
t.Fatal(peers)
}
// Shutdown raft1
if err := raft1.TeardownCluster(nil); err != nil {
t.Fatal(err)
}
// Start Raft
err = raft1.SetupCluster(context.Background(), SetupOpts{})
if err != nil {
t.Fatal(err)
}
peers, err = raft1.Peers(context.Background())
if err != nil {
t.Fatal(err)
}
if len(peers) != 2 {
t.Fatal(peers)
}
compareFSMs(t, raft1.fsm, raft2.fsm)
}
/*
func TestRaft_Snapshot_ErrorRecovery(t *testing.T) {
raft1, dir := getRaft(t, true, false)
raft2, dir2 := getRaft(t, false, false)
raft3, dir3 := getRaft(t, false, false)
defer os.RemoveAll(dir)
defer os.RemoveAll(dir2)
defer os.RemoveAll(dir3)
// Add raft2 to the cluster
addPeer(t, raft1, raft2)
// Write some data
for i := 0; i < 100; i++ {
err := raft1.Put(context.Background(), &physical.Entry{
Key: fmt.Sprintf("key-%d", i),
Value: []byte(fmt.Sprintf("value-%d", i)),
})
if err != nil {
t.Fatal(err)
}
}
// Take a snapshot on each node to ensure we no longer have older logs
snapFuture := raft1.raft.Snapshot()
if err := snapFuture.Error(); err != nil {
t.Fatal(err)
}
stepDownLeader(t, raft1)
leader := waitForLeader(t, raft1, raft2)
snapFuture = leader.raft.Snapshot()
if err := snapFuture.Error(); err != nil {
t.Fatal(err)
}
// Advance FSM's index past snapshot index
leader.Put(context.Background(), &physical.Entry{
Key: "key",
Value: []byte("value"),
})
// Error on snapshot restore
raft3.fsm.testSnapshotRestoreError = true
// Add raft3 to the cluster
addPeer(t, leader, raft3)
time.Sleep(2 * time.Second)
// Restart the failing node to make sure fresh state does not have invalid
// values.
if err := raft3.TeardownCluster(nil); err != nil {
t.Fatal(err)
}
// Ensure the databases are not equal
if err := compareFSMsWithErr(t, leader.fsm, raft3.fsm); err == nil {
t.Fatal("nil error")
}
// Remove error and make sure we can reconcile state
raft3.fsm.testSnapshotRestoreError = false
// Step down leader node
stepDownLeader(t, leader)
leader = waitForLeader(t, raft1, raft2)
// Start Raft3
if err := raft3.SetupCluster(context.Background(), SetupOpts{}); err != nil {
t.Fatal(err)
}
connectPeers(raft1, raft2, raft3)
waitForLeader(t, raft1, raft2)
time.Sleep(5 * time.Second)
// Make sure state gets re-replicated.
compareFSMs(t, raft1.fsm, raft3.fsm)
}*/
func TestRaft_Snapshot_Take_Restore(t *testing.T) {
raft1, dir := getRaft(t, true, false)
defer os.RemoveAll(dir)
raft2, dir2 := getRaft(t, false, false)
defer os.RemoveAll(dir2)
addPeer(t, raft1, raft2)
// Write some data
for i := 0; i < 100; i++ {
err := raft1.Put(context.Background(), &physical.Entry{
Key: fmt.Sprintf("key-%d", i),
Value: []byte(fmt.Sprintf("value-%d", i)),
})
if err != nil {
t.Fatal(err)
}
}
recorder := httptest.NewRecorder()
snap := logical.NewHTTPResponseWriter(recorder)
err := raft1.Snapshot(snap, nil)
if err != nil {
t.Fatal(err)
}
// Write some more data
for i := 100; i < 200; i++ {
err := raft1.Put(context.Background(), &physical.Entry{
Key: fmt.Sprintf("key-%d", i),
Value: []byte(fmt.Sprintf("value-%d", i)),
})
if err != nil {
t.Fatal(err)
}
}
snapFile, cleanup, metadata, err := raft1.WriteSnapshotToTemp(ioutil.NopCloser(recorder.Body), nil)
if err != nil {
t.Fatal(err)
}
defer cleanup()
err = raft1.RestoreSnapshot(context.Background(), metadata, snapFile)
if err != nil {
t.Fatal(err)
}
// make sure we don't have the second batch of writes
for i := 100; i < 200; i++ {
{
value, err := raft1.Get(context.Background(), fmt.Sprintf("key-%d", i))
if err != nil {
t.Fatal(err)
}
if value != nil {
t.Fatal("didn't remove data")
}
}
{
value, err := raft2.Get(context.Background(), fmt.Sprintf("key-%d", i))
if err != nil {
t.Fatal(err)
}
if value != nil {
t.Fatal("didn't remove data")
}
}
}
time.Sleep(10 * time.Second)
compareFSMs(t, raft1.fsm, raft2.fsm)
}
func TestBoltSnapshotStore_CreateSnapshotMissingParentDir(t *testing.T) {
parent, err := ioutil.TempDir("", "raft")
if err != nil {
t.Fatalf("err: %v ", err)
}
defer os.RemoveAll(parent)
dir, err := ioutil.TempDir(parent, "raft")
if err != nil {
t.Fatalf("err: %v ", err)
}
logger := hclog.New(&hclog.LoggerOptions{
Name: "raft",
Level: hclog.Trace,
})
snap, err := NewBoltSnapshotStore(dir, logger, nil)
if err != nil {
t.Fatalf("err: %v", err)
}
os.RemoveAll(parent)
_, trans := raft.NewInmemTransport(raft.NewInmemAddr())
sink, err := snap.Create(raft.SnapshotVersionMax, 10, 3, raft.Configuration{}, 0, trans)
if err != nil {
t.Fatal(err)
}
defer sink.Cancel()
_, err = sink.Write([]byte("test"))
if err != nil {
t.Fatalf("should not fail when using non existing parent: %s", err)
}
// Ensure the snapshot file exists
_, err = os.Stat(filepath.Join(snap.path, sink.ID()+tmpSuffix, databaseFilename))
if err != nil {
t.Fatal(err)
}
}
func TestBoltSnapshotStore_Listing(t *testing.T) {
// Create a test dir
parent, err := ioutil.TempDir("", "raft")
if err != nil {
t.Fatalf("err: %v ", err)
}
defer os.RemoveAll(parent)
dir, err := ioutil.TempDir(parent, "raft")
if err != nil {
t.Fatalf("err: %v ", err)
}
logger := hclog.New(&hclog.LoggerOptions{
Name: "raft",
Level: hclog.Trace,
})
fsm, err := NewFSM(parent, logger)
if err != nil {
t.Fatal(err)
}
snap, err := NewBoltSnapshotStore(dir, logger, fsm)
if err != nil {
t.Fatalf("err: %v", err)
}
// FSM has no data, should have empty snapshot list
snaps, err := snap.List()
if err != nil {
t.Fatalf("err: %v", err)
}
if len(snaps) != 0 {
t.Fatalf("expect 0 snapshots: %v", snaps)
}
// Move the fsm forward
err = fsm.witnessSnapshot(&raft.SnapshotMeta{
Index: 100,
Term: 20,
Configuration: raft.Configuration{},
ConfigurationIndex: 0,
})
if err != nil {
t.Fatal(err)
}
snaps, err = snap.List()
if err != nil {
t.Fatal(err)
}
if len(snaps) != 1 {
t.Fatalf("expect 1 snapshots: %v", snaps)
}
if snaps[0].Index != 100 || snaps[0].Term != 20 {
t.Fatalf("bad snapshot: %+v", snaps[0])
}
if snaps[0].ID != boltSnapshotID {
t.Fatalf("bad snapshot: %+v", snaps[0])
}
}
func TestBoltSnapshotStore_CreateInstallSnapshot(t *testing.T) {
// Create a test dir
parent, err := ioutil.TempDir("", "raft")
if err != nil {
t.Fatalf("err: %v ", err)
}
defer os.RemoveAll(parent)
dir, err := ioutil.TempDir(parent, "raft")
if err != nil {
t.Fatalf("err: %v ", err)
}
logger := hclog.New(&hclog.LoggerOptions{
Name: "raft",
Level: hclog.Trace,
})
fsm, err := NewFSM(parent, logger)
if err != nil {
t.Fatal(err)
}
defer fsm.Close()
snap, err := NewBoltSnapshotStore(dir, logger, fsm)
if err != nil {
t.Fatalf("err: %v", err)
}
// Check no snapshots
snaps, err := snap.List()
if err != nil {
t.Fatalf("err: %v", err)
}
if len(snaps) != 0 {
t.Fatalf("did not expect any snapshots: %v", snaps)
}
// Create a new sink
var configuration raft.Configuration
configuration.Servers = append(configuration.Servers, raft.Server{
Suffrage: raft.Voter,
ID: raft.ServerID("my id"),
Address: raft.ServerAddress("over here"),
})
_, trans := raft.NewInmemTransport(raft.NewInmemAddr())
sink, err := snap.Create(raft.SnapshotVersionMax, 10, 3, configuration, 2, trans)
if err != nil {
t.Fatalf("err: %v", err)
}
protoWriter := NewDelimitedWriter(sink)
err = fsm.Put(context.Background(), &physical.Entry{
Key: "test-key",
Value: []byte("test-value"),
})
if err != nil {
t.Fatal(err)
}
err = fsm.Put(context.Background(), &physical.Entry{
Key: "test-key1",
Value: []byte("test-value1"),
})
if err != nil {
t.Fatal(err)
}
// Write to the sink
err = protoWriter.WriteMsg(&pb.StorageEntry{
Key: "test-key",
Value: []byte("test-value"),
})
if err != nil {
t.Fatalf("err: %v", err)
}
err = protoWriter.WriteMsg(&pb.StorageEntry{
Key: "test-key1",
Value: []byte("test-value1"),
})
if err != nil {
t.Fatalf("err: %v", err)
}
// Done!
err = sink.Close()
if err != nil {
t.Fatalf("err: %v", err)
}
// Read the snapshot
meta, r, err := snap.Open(sink.ID())
if err != nil {
t.Fatalf("err: %v", err)
}
// Check the latest
if meta.Index != 10 {
t.Fatalf("bad snapshot: %+v", meta)
}
if meta.Term != 3 {
t.Fatalf("bad snapshot: %+v", meta)
}
if !reflect.DeepEqual(meta.Configuration, configuration) {
t.Fatalf("bad snapshot: %+v", meta)
}
if meta.ConfigurationIndex != 2 {
t.Fatalf("bad snapshot: %+v", meta)
}
installer, ok := r.(*boltSnapshotInstaller)
if !ok {
t.Fatal("expected snapshot installer object")
}
newFSM, err := NewFSM(filepath.Dir(installer.Filename()), logger)
if err != nil {
t.Fatal(err)
}
err = compareDBs(t, fsm.getDB(), newFSM.getDB(), true)
if err != nil {
t.Fatal(err)
}
// Make sure config data is different
err = compareDBs(t, fsm.getDB(), newFSM.getDB(), false)
if err == nil {
t.Fatal("expected error")
}
if err := newFSM.Close(); err != nil {
t.Fatal(err)
}
err = fsm.Restore(installer)
if err != nil {
t.Fatal(err)
}
for i := 0; i < 2; i++ {
latestIndex, latestConfigRaw := fsm.LatestState()
latestConfigIndex, latestConfig := protoConfigurationToRaftConfiguration(latestConfigRaw)
if latestIndex.Index != 10 {
t.Fatalf("bad install: %+v", latestIndex)
}
if latestIndex.Term != 3 {
t.Fatalf("bad install: %+v", latestIndex)
}
if !reflect.DeepEqual(latestConfig, configuration) {
t.Fatalf("bad install: %+v", latestConfig)
}
if latestConfigIndex != 2 {
t.Fatalf("bad install: %+v", latestConfigIndex)
}
v, err := fsm.Get(context.Background(), "test-key")
if err != nil {
t.Fatal(err)
}
if !bytes.Equal(v.Value, []byte("test-value")) {
t.Fatalf("bad: %+v", v)
}
v, err = fsm.Get(context.Background(), "test-key1")
if err != nil {
t.Fatal(err)
}
if !bytes.Equal(v.Value, []byte("test-value1")) {
t.Fatalf("bad: %+v", v)
}
// Close/Reopen the db and make sure we still match
fsm.Close()
fsm, err = NewFSM(parent, logger)
if err != nil {
t.Fatal(err)
}
}
}
func TestBoltSnapshotStore_CancelSnapshot(t *testing.T) {
// Create a test dir
dir, err := ioutil.TempDir("", "raft")
if err != nil {
t.Fatalf("err: %v ", err)
}
defer os.RemoveAll(dir)
logger := hclog.New(&hclog.LoggerOptions{
Name: "raft",
Level: hclog.Trace,
})
snap, err := NewBoltSnapshotStore(dir, logger, nil)
if err != nil {
t.Fatalf("err: %v", err)
}
_, trans := raft.NewInmemTransport(raft.NewInmemAddr())
sink, err := snap.Create(raft.SnapshotVersionMax, 10, 3, raft.Configuration{}, 0, trans)
if err != nil {
t.Fatal(err)
}
_, err = sink.Write([]byte("test"))
if err != nil {
t.Fatalf("should not fail when using non existing parent: %s", err)
}
// Ensure the snapshot file exists
_, err = os.Stat(filepath.Join(snap.path, sink.ID()+tmpSuffix, databaseFilename))
if err != nil {
t.Fatal(err)
}
// Cancel the snapshot! Should delete
err = sink.Cancel()
if err != nil {
t.Fatalf("err: %v", err)
}
// Ensure the snapshot file does not exist
_, err = os.Stat(filepath.Join(snap.path, sink.ID()+tmpSuffix, databaseFilename))
if !os.IsNotExist(err) {
t.Fatal(err)
}
// Make sure future writes fail
_, err = sink.Write([]byte("test"))
if err == nil {
t.Fatal("expected write to fail")
}
}
func TestBoltSnapshotStore_BadPerm(t *testing.T) {
var err error
if runtime.GOOS == "windows" {
t.Skip("skipping file permission test on windows")
}
// Create a temp dir
var dir1 string
dir1, err = ioutil.TempDir("", "raft")
if err != nil {
t.Fatalf("err: %s", err)
}
defer os.RemoveAll(dir1)
// Create a sub dir and remove all permissions
var dir2 string
dir2, err = ioutil.TempDir(dir1, "badperm")
if err != nil {
t.Fatalf("err: %s", err)
}
if err = os.Chmod(dir2, 000); err != nil {
t.Fatalf("err: %s", err)
}
defer os.Chmod(dir2, 777) // Set perms back for delete
logger := hclog.New(&hclog.LoggerOptions{
Name: "raft",
Level: hclog.Trace,
})
_, err = NewBoltSnapshotStore(dir2, logger, nil)
if err == nil {
t.Fatalf("should fail to use dir with bad perms")
}
}
func TestBoltSnapshotStore_CloseFailure(t *testing.T) {
// Create a test dir
dir, err := ioutil.TempDir("", "raft")
if err != nil {
t.Fatalf("err: %v ", err)
}
defer os.RemoveAll(dir)
logger := hclog.New(&hclog.LoggerOptions{
Name: "raft",
Level: hclog.Trace,
})
snap, err := NewBoltSnapshotStore(dir, logger, nil)
if err != nil {
t.Fatalf("err: %v", err)
}
_, trans := raft.NewInmemTransport(raft.NewInmemAddr())
sink, err := snap.Create(raft.SnapshotVersionMax, 10, 3, raft.Configuration{}, 0, trans)
if err != nil {
t.Fatal(err)
}
// This should stash an error value
_, err = sink.Write([]byte("test"))
if err != nil {
t.Fatalf("should not fail when using non existing parent: %s", err)
}
// Cancel the snapshot! Should delete
err = sink.Close()
if err == nil {
t.Fatalf("expected error")
}
// Ensure the snapshot file does not exist
_, err = os.Stat(filepath.Join(snap.path, sink.ID()+tmpSuffix, databaseFilename))
if !os.IsNotExist(err) {
t.Fatal(err)
}
// Make sure future writes fail
_, err = sink.Write([]byte("test"))
if err == nil {
t.Fatal("expected write to fail")
}
}