rclone/vfs/vfscache/item_test.go
Nick Craig-Wood 184459ba8f vfs: fix stale data when using --vfs-cache-mode full
Before this change the VFS cache could get into a state where when an
object was updated remotely, the fingerprint of the item was correct
for the new object but the data in the VFS cache was for the old
object.

This fixes the problem by updating the fingerprint of the item at the
point we remove the stale data. The empty cache item now represents
the new item even though it has no data in.

This stops the fallback code for an empty fingerprint running (used
when we are writing items to the cache instead of reading them) which
was causing the problem.

Fixes #6053
See: https://forum.rclone.org/t/cached-webdav-mount-fingerprints-get-nuked-on-ls/43974/
2024-01-15 11:12:59 +00:00

590 lines
14 KiB
Go

package vfscache
// FIXME need to test async writeback here
import (
"context"
"fmt"
"io"
"math/rand"
"os"
"sync"
"testing"
"time"
"github.com/rclone/rclone/fs"
"github.com/rclone/rclone/fstest"
"github.com/rclone/rclone/lib/random"
"github.com/rclone/rclone/lib/readers"
"github.com/rclone/rclone/vfs/vfscommon"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
)
var zeroes = string(make([]byte, 100))
func newItemTestCache(t *testing.T) (r *fstest.Run, c *Cache) {
opt := vfscommon.DefaultOpt
// Disable the cache cleaner as it interferes with these tests
opt.CachePollInterval = 0
// Disable synchronous write
opt.WriteBack = 0
return newTestCacheOpt(t, opt)
}
// Check the object has contents
func checkObject(t *testing.T, r *fstest.Run, remote string, contents string) {
obj, err := r.Fremote.NewObject(context.Background(), remote)
require.NoError(t, err)
in, err := obj.Open(context.Background())
require.NoError(t, err)
buf, err := io.ReadAll(in)
require.NoError(t, err)
require.NoError(t, in.Close())
assert.Equal(t, contents, string(buf))
}
func newFileLength(t *testing.T, r *fstest.Run, c *Cache, remote string, length int) (contents string, obj fs.Object, item *Item) {
contents = random.String(length)
r.WriteObject(context.Background(), remote, contents, time.Now())
item, _ = c.get(remote)
obj, err := r.Fremote.NewObject(context.Background(), remote)
require.NoError(t, err)
return
}
func newFile(t *testing.T, r *fstest.Run, c *Cache, remote string) (contents string, obj fs.Object, item *Item) {
return newFileLength(t, r, c, remote, 100)
}
func TestItemExists(t *testing.T) {
_, c := newItemTestCache(t)
item, _ := c.get("potato")
assert.False(t, item.Exists())
require.NoError(t, item.Open(nil))
assert.True(t, item.Exists())
require.NoError(t, item.Close(nil))
assert.True(t, item.Exists())
item.remove("test")
assert.False(t, item.Exists())
}
func TestItemGetSize(t *testing.T) {
r, c := newItemTestCache(t)
item, _ := c.get("potato")
require.NoError(t, item.Open(nil))
size, err := item.GetSize()
require.NoError(t, err)
assert.Equal(t, int64(0), size)
n, err := item.WriteAt([]byte("hello"), 0)
require.NoError(t, err)
assert.Equal(t, 5, n)
size, err = item.GetSize()
require.NoError(t, err)
assert.Equal(t, int64(5), size)
require.NoError(t, item.Close(nil))
checkObject(t, r, "potato", "hello")
}
func TestItemDirty(t *testing.T) {
r, c := newItemTestCache(t)
item, _ := c.get("potato")
require.NoError(t, item.Open(nil))
assert.Equal(t, false, item.IsDirty())
n, err := item.WriteAt([]byte("hello"), 0)
require.NoError(t, err)
assert.Equal(t, 5, n)
assert.Equal(t, true, item.IsDirty())
require.NoError(t, item.Close(nil))
// Sync writeback so expect clean here
assert.Equal(t, false, item.IsDirty())
item.Dirty()
assert.Equal(t, true, item.IsDirty())
checkObject(t, r, "potato", "hello")
}
func TestItemSync(t *testing.T) {
_, c := newItemTestCache(t)
item, _ := c.get("potato")
require.Error(t, item.Sync())
require.NoError(t, item.Open(nil))
require.NoError(t, item.Sync())
require.NoError(t, item.Close(nil))
}
func TestItemTruncateNew(t *testing.T) {
r, c := newItemTestCache(t)
item, _ := c.get("potato")
require.Error(t, item.Truncate(0))
require.NoError(t, item.Open(nil))
require.NoError(t, item.Truncate(100))
size, err := item.GetSize()
require.NoError(t, err)
assert.Equal(t, int64(100), size)
// Check the Close callback works
callbackCalled := false
callback := func(o fs.Object) {
callbackCalled = true
assert.Equal(t, "potato", o.Remote())
assert.Equal(t, int64(100), o.Size())
}
require.NoError(t, item.Close(callback))
assert.True(t, callbackCalled)
checkObject(t, r, "potato", zeroes)
}
func TestItemTruncateExisting(t *testing.T) {
r, c := newItemTestCache(t)
contents, obj, item := newFile(t, r, c, "existing")
require.Error(t, item.Truncate(40))
checkObject(t, r, "existing", contents)
require.NoError(t, item.Open(obj))
require.NoError(t, item.Truncate(40))
require.NoError(t, item.Truncate(60))
require.NoError(t, item.Close(nil))
checkObject(t, r, "existing", contents[:40]+zeroes[:20])
}
func TestItemReadAt(t *testing.T) {
r, c := newItemTestCache(t)
contents, obj, item := newFile(t, r, c, "existing")
buf := make([]byte, 10)
_, err := item.ReadAt(buf, 10)
require.Error(t, err)
require.NoError(t, item.Open(obj))
n, err := item.ReadAt(buf, 10)
assert.Equal(t, 10, n)
require.NoError(t, err)
assert.Equal(t, contents[10:20], string(buf[:n]))
n, err = item.ReadAt(buf, 95)
assert.Equal(t, 5, n)
assert.Equal(t, io.EOF, err)
assert.Equal(t, contents[95:], string(buf[:n]))
n, err = item.ReadAt(buf, 1000)
assert.Equal(t, 0, n)
assert.Equal(t, io.EOF, err)
assert.Equal(t, contents[:0], string(buf[:n]))
n, err = item.ReadAt(buf, -1)
assert.Equal(t, 0, n)
assert.Equal(t, io.EOF, err)
assert.Equal(t, contents[:0], string(buf[:n]))
require.NoError(t, item.Close(nil))
}
func TestItemWriteAtNew(t *testing.T) {
r, c := newItemTestCache(t)
item, _ := c.get("potato")
buf := make([]byte, 10)
_, err := item.WriteAt(buf, 10)
require.Error(t, err)
require.NoError(t, item.Open(nil))
assert.Equal(t, int64(0), item.getDiskSize())
n, err := item.WriteAt([]byte("HELLO"), 10)
require.NoError(t, err)
assert.Equal(t, 5, n)
// FIXME we account for the sparse data we've "written" to
// disk here so this is actually 5 bytes higher than expected
assert.Equal(t, int64(15), item.getDiskSize())
n, err = item.WriteAt([]byte("THEND"), 20)
require.NoError(t, err)
assert.Equal(t, 5, n)
assert.Equal(t, int64(25), item.getDiskSize())
require.NoError(t, item.Close(nil))
checkObject(t, r, "potato", zeroes[:10]+"HELLO"+zeroes[:5]+"THEND")
}
func TestItemWriteAtExisting(t *testing.T) {
r, c := newItemTestCache(t)
contents, obj, item := newFile(t, r, c, "existing")
require.NoError(t, item.Open(obj))
n, err := item.WriteAt([]byte("HELLO"), 10)
require.NoError(t, err)
assert.Equal(t, 5, n)
n, err = item.WriteAt([]byte("THEND"), 95)
require.NoError(t, err)
assert.Equal(t, 5, n)
n, err = item.WriteAt([]byte("THEVERYEND"), 120)
require.NoError(t, err)
assert.Equal(t, 10, n)
require.NoError(t, item.Close(nil))
checkObject(t, r, "existing", contents[:10]+"HELLO"+contents[15:95]+"THEND"+zeroes[:20]+"THEVERYEND")
}
func TestItemLoadMeta(t *testing.T) {
r, c := newItemTestCache(t)
contents, obj, item := newFile(t, r, c, "existing")
_ = contents
// Open the object to create metadata for it
require.NoError(t, item.Open(obj))
require.NoError(t, item.Close(nil))
info := item.info
// Remove the item from the cache
c.mu.Lock()
delete(c.item, item.name)
c.mu.Unlock()
// Reload the item so we have to load the metadata
item2, _ := c._get("existing")
require.NoError(t, item2.Open(obj))
info2 := item.info
require.NoError(t, item2.Close(nil))
// Check that the item is different
assert.NotEqual(t, item, item2)
// ... but the info is the same
assert.Equal(t, info, info2)
}
func TestItemReload(t *testing.T) {
r, c := newItemTestCache(t)
contents, obj, item := newFile(t, r, c, "existing")
_ = contents
// Open the object to create metadata for it
require.NoError(t, item.Open(obj))
// Make it dirty
n, err := item.WriteAt([]byte("THEENDMYFRIEND"), 95)
require.NoError(t, err)
assert.Equal(t, 14, n)
assert.True(t, item.IsDirty())
// Close the file to pacify Windows, but don't call item.Close()
item.mu.Lock()
require.NoError(t, item.fd.Close())
item.fd = nil
item.mu.Unlock()
// Remove the item from the cache
c.mu.Lock()
delete(c.item, item.name)
c.mu.Unlock()
// Reload the item so we have to load the metadata and restart
// the transfer
item2, _ := c._get("existing")
require.NoError(t, item2.reload(context.Background()))
assert.False(t, item2.IsDirty())
// Check that the item is different
assert.NotEqual(t, item, item2)
// And check the contents got written back to the remote
checkObject(t, r, "existing", contents[:95]+"THEENDMYFRIEND")
// And check that AddVirtual was called
assert.Equal(t, []avInfo{
{Remote: "existing", Size: 109, IsDir: false},
}, avInfos)
}
func TestItemReloadRemoteGone(t *testing.T) {
r, c := newItemTestCache(t)
contents, obj, item := newFile(t, r, c, "existing")
_ = contents
// Open the object to create metadata for it
require.NoError(t, item.Open(obj))
size, err := item.GetSize()
require.NoError(t, err)
assert.Equal(t, int64(100), size)
// Read something to instantiate the cache file
buf := make([]byte, 10)
_, err = item.ReadAt(buf, 10)
require.NoError(t, err)
// Test cache file present
_, err = os.Stat(item.c.toOSPath(item.name))
require.NoError(t, err)
require.NoError(t, item.Close(nil))
// Remove the remote object
require.NoError(t, obj.Remove(context.Background()))
// Re-open with no object
require.NoError(t, item.Open(nil))
// Check size is now 0
size, err = item.GetSize()
require.NoError(t, err)
assert.Equal(t, int64(0), size)
// Test cache file is now empty
fi, err := os.Stat(item.c.toOSPath(item.name))
require.NoError(t, err)
assert.Equal(t, int64(0), fi.Size())
require.NoError(t, item.Close(nil))
}
func TestItemReloadCacheStale(t *testing.T) {
r, c := newItemTestCache(t)
contents, obj, item := newFile(t, r, c, "existing")
// Open the object to create metadata for it
require.NoError(t, item.Open(obj))
size, err := item.GetSize()
require.NoError(t, err)
assert.Equal(t, int64(100), size)
// Read something to instantiate the cache file
buf := make([]byte, 10)
_, err = item.ReadAt(buf, 10)
require.NoError(t, err)
// Test cache file present
_, err = os.Stat(item.c.toOSPath(item.name))
require.NoError(t, err)
require.NoError(t, item.Close(nil))
// Update the remote to something different
contents2, obj, item := newFileLength(t, r, c, "existing", 110)
assert.NotEqual(t, contents, contents2)
// Re-open with updated object
oldFingerprint := item.info.Fingerprint
assert.NotEqual(t, "", oldFingerprint)
require.NoError(t, item.Open(obj))
// Make sure fingerprint was updated
assert.NotEqual(t, oldFingerprint, item.info.Fingerprint)
assert.NotEqual(t, "", item.info.Fingerprint)
// Check size is now 110
size, err = item.GetSize()
require.NoError(t, err)
assert.Equal(t, int64(110), size)
// Test cache file is now correct size
fi, err := os.Stat(item.c.toOSPath(item.name))
require.NoError(t, err)
assert.Equal(t, int64(110), fi.Size())
// Write to the file to make it dirty
// This checks we aren't re-using stale data
n, err := item.WriteAt([]byte("HELLO"), 0)
require.NoError(t, err)
assert.Equal(t, 5, n)
assert.Equal(t, true, item.IsDirty())
require.NoError(t, item.Close(nil))
// Now check with all that swizzling stuff around that the
// object is correct
checkObject(t, r, "existing", "HELLO"+contents2[5:])
}
func TestItemReadWrite(t *testing.T) {
r, c := newItemTestCache(t)
const (
size = 50*1024*1024 + 123
fileName = "large"
)
item, _ := c.get(fileName)
require.NoError(t, item.Open(nil))
// Create the test file
in := readers.NewPatternReader(size)
buf := make([]byte, 1024*1024)
buf2 := make([]byte, 1024*1024)
offset := int64(0)
for {
n, err := in.Read(buf)
n2, err2 := item.WriteAt(buf[:n], offset)
offset += int64(n2)
require.NoError(t, err2)
require.Equal(t, n, n2)
if err == io.EOF {
break
}
require.NoError(t, err)
}
// Check it is the right size
readSize, err := item.GetSize()
require.NoError(t, err)
assert.Equal(t, int64(size), readSize)
require.NoError(t, item.Close(nil))
assert.False(t, item.remove(fileName))
obj, err := r.Fremote.NewObject(context.Background(), fileName)
require.NoError(t, err)
assert.Equal(t, int64(size), obj.Size())
// read and check a block of size N at offset
// It returns eof true if the end of file has been reached
readCheckBuf := func(t *testing.T, in io.ReadSeeker, buf, buf2 []byte, item *Item, offset int64, N int) (n int, eof bool) {
what := fmt.Sprintf("buf=%p, buf2=%p, item=%p, offset=%d, N=%d", buf, buf2, item, offset, N)
n, err := item.ReadAt(buf, offset)
_, err2 := in.Seek(offset, io.SeekStart)
require.NoError(t, err2, what)
n2, err2 := in.Read(buf2[:n])
require.Equal(t, n, n2, what)
assert.Equal(t, buf[:n], buf2[:n2], what)
assert.Equal(t, buf[:n], buf2[:n2], what)
if err == io.EOF {
return n, true
}
require.NoError(t, err, what)
require.NoError(t, err2, what)
return n, false
}
readCheck := func(t *testing.T, item *Item, offset int64, N int) (n int, eof bool) {
return readCheckBuf(t, in, buf, buf2, item, offset, N)
}
// Read it back sequentially
t.Run("Sequential", func(t *testing.T) {
require.NoError(t, item.Open(obj))
assert.False(t, item.present())
offset := int64(0)
for {
n, eof := readCheck(t, item, offset, len(buf))
offset += int64(n)
if eof {
break
}
}
assert.Equal(t, int64(size), offset)
require.NoError(t, item.Close(nil))
assert.False(t, item.remove(fileName))
})
// Read it back randomly
t.Run("Random", func(t *testing.T) {
require.NoError(t, item.Open(obj))
assert.False(t, item.present())
for !item.present() {
blockSize := rand.Intn(len(buf))
offset := rand.Int63n(size+2*int64(blockSize)) - int64(blockSize)
if offset < 0 {
offset = 0
}
_, _ = readCheck(t, item, offset, blockSize)
}
require.NoError(t, item.Close(nil))
assert.False(t, item.remove(fileName))
})
// Read it back randomly concurrently
t.Run("RandomConcurrent", func(t *testing.T) {
require.NoError(t, item.Open(obj))
assert.False(t, item.present())
var wg sync.WaitGroup
for i := 0; i < 8; i++ {
wg.Add(1)
go func() {
defer wg.Done()
in := readers.NewPatternReader(size)
buf := make([]byte, 1024*1024)
buf2 := make([]byte, 1024*1024)
for !item.present() {
blockSize := rand.Intn(len(buf))
offset := rand.Int63n(size+2*int64(blockSize)) - int64(blockSize)
if offset < 0 {
offset = 0
}
_, _ = readCheckBuf(t, in, buf, buf2, item, offset, blockSize)
}
}()
}
wg.Wait()
require.NoError(t, item.Close(nil))
assert.False(t, item.remove(fileName))
})
// Read it back in reverse which creates the maximum number of
// downloaders
t.Run("Reverse", func(t *testing.T) {
require.NoError(t, item.Open(obj))
assert.False(t, item.present())
offset := int64(size)
for {
blockSize := len(buf)
offset -= int64(blockSize)
if offset < 0 {
offset = 0
blockSize += int(offset)
}
_, _ = readCheck(t, item, offset, blockSize)
if offset == 0 {
break
}
}
require.NoError(t, item.Close(nil))
assert.False(t, item.remove(fileName))
})
}