Files
kopia/internal/cache/persistent_lru_cache_test.go
Julio López 961a39039b refactor(general): use errors.New where appropriate (#4160)
Replaces 'errors.Errorf\("([^"]+)"\)' => 'errors.New("\1")'
2024-10-05 19:05:00 -07:00

375 lines
11 KiB
Go

package cache_test
import (
"bytes"
"context"
"testing"
"time"
"github.com/pkg/errors"
"github.com/stretchr/testify/require"
"github.com/kopia/kopia/internal/blobtesting"
"github.com/kopia/kopia/internal/cache"
"github.com/kopia/kopia/internal/cacheprot"
"github.com/kopia/kopia/internal/clock"
"github.com/kopia/kopia/internal/fault"
"github.com/kopia/kopia/internal/gather"
"github.com/kopia/kopia/internal/testlogging"
"github.com/kopia/kopia/internal/testutil"
"github.com/kopia/kopia/repo/blob"
)
func TestPersistentLRUCache(t *testing.T) {
ctx := testlogging.ContextWithLevel(t, testlogging.LevelInfo)
const maxSizeBytes = 1000
cs := blobtesting.NewMapStorageWithLimit(blobtesting.DataMap{}, nil, nil, maxSizeBytes).(cache.Storage)
pc, err := cache.NewPersistentCache(ctx, "testing", cs, cacheprot.ChecksumProtection([]byte{1, 2, 3}), cache.SweepSettings{
MaxSizeBytes: maxSizeBytes,
TouchThreshold: cache.DefaultTouchThreshold,
}, nil, clock.Now)
require.NoError(t, err)
var tmp gather.WriteBuffer
defer tmp.Close()
if got := pc.GetFull(ctx, "key", &tmp); got {
t.Fatalf("unexpected cache hit on empty cache")
}
someData := bytes.Repeat([]byte{1}, 300)
pc.Put(ctx, "key1", gather.FromSlice(someData))
verifyBlobExists(ctx, t, cs, "key1")
pc.Put(ctx, "key2", gather.FromSlice(someData))
verifyBlobExists(ctx, t, cs, "key2")
pc.Put(ctx, "key3", gather.FromSlice(someData))
verifyBlobExists(ctx, t, cs, "key3")
pc.Put(ctx, "key4", gather.FromSlice(someData))
verifyBlobExists(ctx, t, cs, "key4")
require.True(t, pc.GetFull(ctx, "key2", &tmp))
if got, want := tmp.ToByteSlice(), someData; !bytes.Equal(got, want) {
t.Fatalf("invalid data retrieved from cache: %x", got)
}
// final sweep is performed on close at which time key1 becomes candidate
// for expulsion from cache because it's the oldest and we have 1200 bytes in the cache
// but the limit is only 1000.
pc.Close(ctx)
verifyBlobDoesNotExist(ctx, t, cs, "key1")
verifyBlobExists(ctx, t, cs, "key2")
verifyBlobExists(ctx, t, cs, "key3")
verifyBlobExists(ctx, t, cs, "key4")
pc, err = cache.NewPersistentCache(ctx, "testing", cs, cacheprot.ChecksumProtection([]byte{1, 2, 3}), cache.SweepSettings{
MaxSizeBytes: maxSizeBytes,
TouchThreshold: cache.DefaultTouchThreshold,
}, nil, clock.Now)
require.NoError(t, err)
verifyCached(ctx, t, pc, "key1", nil)
verifyCached(ctx, t, pc, "key2", someData)
verifyCached(ctx, t, pc, "key3", someData)
verifyCached(ctx, t, pc, "key4", someData)
// create another persistent cache based on the same storage but wrong protection key.
// all reads from cache will be invalid, which means GetOrLoad will fetch them from the source.
pc2, err := cache.NewPersistentCache(ctx, "testing", cs, cacheprot.ChecksumProtection([]byte{3, 2, 1}), cache.SweepSettings{
MaxSizeBytes: maxSizeBytes,
TouchThreshold: cache.DefaultTouchThreshold,
}, nil, clock.Now)
require.NoError(t, err)
someError := errors.New("some error")
var tmp2 gather.WriteBuffer
defer tmp2.Close()
require.NoError(t, pc2.GetOrLoad(ctx, "key2", func(output *gather.WriteBuffer) error {
output.Append([]byte{1, 2, 3})
return nil
}, &tmp2))
require.NoError(t, pc2.GetOrLoad(ctx, "key2", func(output *gather.WriteBuffer) error {
return someError
}, &tmp2))
// make sure we received data returned by the callback.
require.Equal(t, []byte{1, 2, 3}, tmp2.ToByteSlice())
// at this point 'cs' was updated with a different checksum, so attempting to read it using
// 'pc' will return cache miss.
verifyCached(ctx, t, pc, "key2", nil)
require.ErrorIs(t, pc2.GetOrLoad(ctx, "key9", func(output *gather.WriteBuffer) error {
return someError
}, &tmp2), someError)
}
type faultyCache struct {
*blobtesting.FaultyStorage
}
func (faultyCache) TouchBlob(ctx context.Context, blobID blob.ID, threshold time.Duration) (time.Time, error) {
return time.Time{}, nil
}
func TestPersistentLRUCache_Invalid(t *testing.T) {
t.Parallel()
ctx := testlogging.ContextWithLevel(t, testlogging.LevelInfo)
someError := errors.New("some error")
st := blobtesting.NewMapStorage(blobtesting.DataMap{}, nil, nil)
fs := blobtesting.NewFaultyStorage(st)
fc := faultyCache{fs}
fs.AddFault(blobtesting.MethodGetMetadata).ErrorInstead(someError)
pc, err := cache.NewPersistentCache(ctx, "test", fc, nil, cache.SweepSettings{}, nil, clock.Now)
require.ErrorIs(t, err, someError)
require.Nil(t, pc)
}
func TestPersistentLRUCache_GetDeletesInvalidBlob(t *testing.T) {
t.Parallel()
ctx := testlogging.ContextWithLevel(t, testlogging.LevelInfo)
someError := errors.New("some error")
data := blobtesting.DataMap{}
const maxSizeBytes = 1000
st := blobtesting.NewMapStorageWithLimit(data, nil, nil, maxSizeBytes)
fs := blobtesting.NewFaultyStorage(st)
fc := faultyCache{fs}
pc, err := cache.NewPersistentCache(ctx, "test", fc, cacheprot.ChecksumProtection([]byte{1, 2, 3}), cache.SweepSettings{MaxSizeBytes: maxSizeBytes}, nil, clock.Now)
require.NoError(t, err)
pc.Put(ctx, "key", gather.FromSlice([]byte{1, 2, 3}))
// corrupt cached data
data["key"][0] ^= 1
var tmp gather.WriteBuffer
defer tmp.Close()
// simulate failure when trying to delete.
fs.AddFault(blobtesting.MethodDeleteBlob).ErrorInstead(someError)
pc.GetFull(ctx, "key", &tmp)
}
func TestPersistentLRUCache_PutIgnoresStorageFailure(t *testing.T) {
t.Parallel()
ctx := testlogging.ContextWithLevel(t, testlogging.LevelInfo)
someError := errors.New("some error")
data := blobtesting.DataMap{}
st := blobtesting.NewMapStorage(data, nil, nil)
fs := blobtesting.NewFaultyStorage(st)
fc := faultyCache{fs}
pc, err := cache.NewPersistentCache(ctx, "test", fc, cacheprot.ChecksumProtection([]byte{1, 2, 3}), cache.SweepSettings{}, nil, clock.Now)
require.NoError(t, err)
fs.AddFault(blobtesting.MethodPutBlob).ErrorInstead(someError)
pc.Put(ctx, "key", gather.FromSlice([]byte{1, 2, 3}))
var tmp gather.WriteBuffer
defer tmp.Close()
require.False(t, pc.GetFull(ctx, "key", &tmp))
require.Equal(t, 1, fs.NumCalls(blobtesting.MethodPutBlob))
}
func TestPersistentLRUCache_SweepMinSweepAge(t *testing.T) {
t.Parallel()
ctx := testlogging.ContextWithLevel(t, testlogging.LevelInfo)
data := blobtesting.DataMap{}
const maxSizeBytes = 1000
st := blobtesting.NewMapStorageWithLimit(data, nil, nil, maxSizeBytes)
fs := blobtesting.NewFaultyStorage(st)
fc := faultyCache{fs}
pc, err := cache.NewPersistentCache(ctx, "test", fc, cacheprot.ChecksumProtection([]byte{1, 2, 3}), cache.SweepSettings{
MaxSizeBytes: maxSizeBytes,
MinSweepAge: 10 * time.Second,
}, nil, clock.Now)
require.NoError(t, err)
pc.Put(ctx, "key", gather.FromSlice([]byte{1, 2, 3}))
pc.Put(ctx, "key2", gather.FromSlice(bytes.Repeat([]byte{1, 2, 3}, 10)))
time.Sleep(1 * time.Second)
// simulate error during final sweep
fs.AddFault(blobtesting.MethodListBlobs).ErrorInstead(errors.New("some error"))
pc.Close(ctx)
// both keys are retained since we're under min sweep age
require.Len(t, data, 2)
}
func TestPersistentLRUCache_SweepIgnoresErrors(t *testing.T) {
t.Parallel()
ctx := testlogging.ContextWithLevel(t, testlogging.LevelInfo)
data := blobtesting.DataMap{}
const maxSizeBytes = 1000
st := blobtesting.NewMapStorageWithLimit(data, nil, nil, maxSizeBytes)
fs := blobtesting.NewFaultyStorage(st)
fc := faultyCache{fs}
pc, err := cache.NewPersistentCache(ctx, "test", fc, cacheprot.ChecksumProtection([]byte{1, 2, 3}), cache.SweepSettings{
MaxSizeBytes: maxSizeBytes,
}, nil, clock.Now)
require.NoError(t, err)
// ignore delete errors forever
fs.AddFault(blobtesting.MethodDeleteBlob).ErrorInstead(errors.New("some delete error")).Repeat(1e6)
pc.Put(ctx, "key", gather.FromSlice([]byte{1, 2, 3}))
pc.Put(ctx, "key2", gather.FromSlice(bytes.Repeat([]byte{1, 2, 3}, 10)))
time.Sleep(500 * time.Millisecond)
// simulate error during sweep
fs.AddFaults(blobtesting.MethodListBlobs, fault.New().ErrorInstead(errors.New("some error")))
time.Sleep(500 * time.Millisecond)
pc.Close(ctx)
// both keys are retained since we're under min sweep age
require.Len(t, data, 2)
}
func TestPersistentLRUCache_Sweep1(t *testing.T) {
ctx := testlogging.ContextWithLevel(t, testlogging.LevelInfo)
data := blobtesting.DataMap{}
const maxSizeBytes = 1
st := blobtesting.NewMapStorageWithLimit(data, nil, nil, maxSizeBytes)
fs := blobtesting.NewFaultyStorage(st)
fc := faultyCache{fs}
pc, err := cache.NewPersistentCache(ctx, "test", fc, cacheprot.ChecksumProtection([]byte{1, 2, 3}), cache.SweepSettings{
MaxSizeBytes: maxSizeBytes,
MinSweepAge: 0 * time.Second,
}, nil, clock.Now)
require.NoError(t, err)
pc.Put(ctx, "key", gather.FromSlice([]byte{1, 2, 3}))
pc.Put(ctx, "key", gather.FromSlice(bytes.Repeat([]byte{1, 2, 3}, 1e6)))
time.Sleep(1 * time.Second)
// simulate error during final sweep
fs.AddFaults(blobtesting.MethodListBlobs, fault.New().ErrorInstead(errors.New("some error")))
pc.Close(ctx)
}
func TestPersistentLRUCacheNil(t *testing.T) {
ctx := testlogging.ContextWithLevel(t, testlogging.LevelInfo)
var pc *cache.PersistentCache
// no-op
pc.Close(ctx)
pc.Put(ctx, "key", gather.FromSlice([]byte{1, 2, 3}))
var tmp gather.WriteBuffer
require.False(t, pc.GetFull(ctx, "key", &tmp))
called := false
dummyError := errors.New("dummy error")
require.ErrorIs(t, pc.GetOrLoad(ctx, "key", func(output *gather.WriteBuffer) error {
called = true
return dummyError
}, &tmp), dummyError)
require.True(t, called)
}
func TestPersistentLRUCache_Defaults(t *testing.T) {
cacheDir := testutil.TempDirectory(t)
ctx := testlogging.ContextWithLevel(t, testlogging.LevelInfo)
const maxSizeBytes = 1000
cs, err := cache.NewStorageOrNil(ctx, cacheDir, maxSizeBytes, "subdir")
require.NoError(t, err)
pc, err := cache.NewPersistentCache(ctx, "testing", cs, nil, cache.SweepSettings{
MaxSizeBytes: maxSizeBytes,
}, nil, clock.Now)
require.NoError(t, err)
defer pc.Close(ctx)
pc.Put(ctx, "key1", gather.FromSlice([]byte{1, 2, 3}))
var tmp gather.WriteBuffer
defer tmp.Close()
cs.GetBlob(ctx, "key1", 0, -1, &tmp)
require.Len(t, tmp.ToByteSlice(), 3)
}
func verifyCached(ctx context.Context, t *testing.T, pc *cache.PersistentCache, key string, want []byte) {
t.Helper()
var tmp gather.WriteBuffer
defer tmp.Close()
if want == nil {
require.False(t, pc.GetFull(ctx, key, &tmp))
} else {
require.True(t, pc.GetFull(ctx, key, &tmp))
if got := tmp.ToByteSlice(); !bytes.Equal(got, want) {
t.Fatalf("invalid cached result for %v: %x, want %x", key, got, want)
}
}
}
func verifyBlobExists(ctx context.Context, t *testing.T, st blob.Storage, blobID blob.ID) {
t.Helper()
if _, err := st.GetMetadata(ctx, blobID); err != nil {
t.Fatalf("blob %v error: %v", blobID, err)
}
}
func verifyBlobDoesNotExist(ctx context.Context, t *testing.T, st blob.Storage, blobID blob.ID) {
t.Helper()
if _, err := st.GetMetadata(ctx, blobID); !errors.Is(err, blob.ErrBlobNotFound) {
t.Fatalf("unexpected blob %v error: %v", blobID, err)
}
}