Files
seaweedfs/weed/s3api/s3api_local_read_fallback_test.go
T
Chris LuandGitHub d9d5fab35b S3: commit GET status only after the first read succeeds (#10930)
streamFromVolumeServers wrote the 200/206 status from filer metadata
before any byte had been fetched from a volume server, so a missing or
corrupted needle surfaced as a broken 200 body and the request metrics
recorded a success. Defer the status commit to the first body write: a
failed first read now returns a clean 500 before headers, while the
wire timing of successful responses is unchanged since net/http buffers
the status line until body bytes arrive anyway.
2026-08-24 16:14:52 -07:00

367 lines
15 KiB
Go

package s3api
import (
"bytes"
"context"
"errors"
"io"
"net/http"
"net/http/httptest"
"testing"
"time"
"github.com/seaweedfs/seaweedfs/weed/filer"
"github.com/seaweedfs/seaweedfs/weed/pb"
"github.com/seaweedfs/seaweedfs/weed/pb/filer_pb"
"github.com/seaweedfs/seaweedfs/weed/remote_storage"
"github.com/seaweedfs/seaweedfs/weed/s3api/s3_constants"
"github.com/seaweedfs/seaweedfs/weed/util/chunk_cache"
"github.com/seaweedfs/seaweedfs/weed/wdclient"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
)
// stubReaderAt stands in for ChunkReadAt in probe unit tests.
type stubReaderAt struct {
n int
err error
}
func (s stubReaderAt) ReadAtWithTime(ctx context.Context, p []byte, offset int64) (int, int64, error) {
return s.n, 0, s.err
}
// blockingReaderAt never returns until the context is cancelled.
type blockingReaderAt struct{}
func (blockingReaderAt) ReadAtWithTime(ctx context.Context, p []byte, offset int64) (int, int64, error) {
<-ctx.Done()
return 0, 0, ctx.Err()
}
func TestProbeReadable(t *testing.T) {
t.Run("readable local copy", func(t *testing.T) {
assert.NoError(t, probeReadable(context.Background(), stubReaderAt{n: 1}, 0, time.Second))
})
t.Run("final byte with trailing EOF counts as readable", func(t *testing.T) {
assert.NoError(t, probeReadable(context.Background(), stubReaderAt{n: 1, err: io.EOF}, 0, time.Second))
})
t.Run("zero-byte EOF is unreadable", func(t *testing.T) {
assert.Error(t, probeReadable(context.Background(), stubReaderAt{n: 0, err: io.EOF}, 0, time.Second))
})
t.Run("zero-byte read without error is unreadable", func(t *testing.T) {
assert.ErrorIs(t, probeReadable(context.Background(), stubReaderAt{n: 0, err: nil}, 0, time.Second), io.ErrUnexpectedEOF)
})
t.Run("read error surfaces", func(t *testing.T) {
boom := errors.New("volume: connection refused")
assert.ErrorIs(t, probeReadable(context.Background(), stubReaderAt{err: boom}, 0, time.Second), boom)
})
t.Run("stuck volume trips the timeout instead of blocking", func(t *testing.T) {
start := time.Now()
err := probeReadable(context.Background(), blockingReaderAt{}, 0, 50*time.Millisecond)
assert.ErrorIs(t, err, context.DeadlineExceeded)
assert.Less(t, time.Since(start), time.Second, "must not block past the probe timeout")
})
}
func TestShouldFallBackToRemote(t *testing.T) {
const size = int64(100)
remoteEntry := func() *filer_pb.Entry {
return &filer_pb.Entry{
Attributes: &filer_pb.FuseAttributes{FileSize: uint64(size)},
RemoteEntry: &filer_pb.RemoteEntry{RemoteSize: size},
}
}
server := func() *S3ApiServer {
return &S3ApiServer{option: &S3ApiServerOption{}}
}
t.Run("matching remote", func(t *testing.T) {
assert.True(t, server().shouldFallBackToRemote(remoteEntry(), size, ""))
})
t.Run("null versionId is treated as unversioned", func(t *testing.T) {
assert.True(t, server().shouldFallBackToRemote(remoteEntry(), size, "null"))
})
t.Run("versioned read cannot use the unversioned remote key", func(t *testing.T) {
assert.False(t, server().shouldFallBackToRemote(remoteEntry(), size, "v123"))
})
t.Run("latest read that resolves to a version cannot use the unversioned key", func(t *testing.T) {
versioned := remoteEntry()
versioned.Extended = map[string][]byte{s3_constants.ExtVersionIdKey: []byte("v9")}
assert.False(t, server().shouldFallBackToRemote(versioned, size, ""))
})
t.Run("no remote entry", func(t *testing.T) {
local := &filer_pb.Entry{Attributes: &filer_pb.FuseAttributes{FileSize: uint64(size)}}
assert.False(t, server().shouldFallBackToRemote(local, size, ""))
})
t.Run("size mismatch is not served as identical bytes", func(t *testing.T) {
assert.False(t, server().shouldFallBackToRemote(remoteEntry(), size+1, ""))
})
}
// The fake filer does not implement LookupVolume, so every chunk read through
// this ReaderCache fails, standing in for an unreachable volume server.
func newLocalReadFallbackServer(t *testing.T, filerAddr pb.ServerAddress) *S3ApiServer {
t.Helper()
s3a := newRemoteCacheTestServer(filerAddr)
fc := wdclient.NewFilerClient(s3a.option.Filers, s3a.option.GrpcDialOption, s3a.option.DataCenter)
s3a.filerClient = fc
s3a.readerCache = filer.NewReaderCache(8, (*chunk_cache.TieredChunkCache)(nil), fc.GetLookupFileIdFunction(), fc)
return s3a
}
// a remote-mounted object whose cached copy is in the metadata but unreadable
func cachedEntry(content []byte) *filer_pb.Entry {
return &filer_pb.Entry{
Name: "obj.bin",
Attributes: &filer_pb.FuseAttributes{FileSize: uint64(len(content))},
Chunks: []*filer_pb.FileChunk{{FileId: "1,0123456789ab", Size: uint64(len(content)), Offset: 0}},
RemoteEntry: &filer_pb.RemoteEntry{RemoteSize: int64(len(content))},
}
}
func TestS3CachedReadFallsBackToRemote(t *testing.T) {
content := []byte("0123456789")
t.Run("unreadable local copy is served from the mounted remote", func(t *testing.T) {
client := &fakeStreamRemoteClient{data: content}
remote_storage.RemoteStorageClientMakers["faketest"] = &fakeStreamRemoteMaker{client: client}
s3a := newLocalReadFallbackServer(t, startStreamThroughFiler(t, "faketest-cachedfail", nil))
w := httptest.NewRecorder()
r := httptest.NewRequest(http.MethodGet, "/mybucket/dir/obj.bin", nil)
err := s3a.streamFromVolumeServers(w, r, cachedEntry(content), "", "mybucket", "dir/obj.bin", "")
require.NoError(t, err)
assert.Equal(t, http.StatusOK, w.Code)
assert.Equal(t, content, w.Body.Bytes())
require.NotNil(t, client.gotLoc, "must read from the mounted remote")
assert.Equal(t, "/data/dir/obj.bin", client.gotLoc.Path)
})
t.Run("range fallback serves the requested window from the remote", func(t *testing.T) {
client := &fakeStreamRemoteClient{data: content}
remote_storage.RemoteStorageClientMakers["faketest"] = &fakeStreamRemoteMaker{client: client}
s3a := newLocalReadFallbackServer(t, startStreamThroughFiler(t, "faketest-cachedrange", nil))
w := httptest.NewRecorder()
r := httptest.NewRequest(http.MethodGet, "/mybucket/dir/obj.bin", nil)
r.Header.Set("Range", "bytes=2-5")
err := s3a.streamFromVolumeServers(w, r, cachedEntry(content), "", "mybucket", "dir/obj.bin", "")
require.NoError(t, err)
assert.Equal(t, http.StatusPartialContent, w.Code)
assert.Equal(t, content[2:6], w.Body.Bytes())
assert.Equal(t, int64(2), client.gotOffset)
assert.Equal(t, int64(4), client.gotSize)
})
t.Run("a local-only object gets a clean 500, not a broken 200 body", func(t *testing.T) {
client := &fakeStreamRemoteClient{data: content}
remote_storage.RemoteStorageClientMakers["faketest"] = &fakeStreamRemoteMaker{client: client}
s3a := newLocalReadFallbackServer(t, startStreamThroughFiler(t, "faketest-nofallback", nil))
local := cachedEntry(content)
local.RemoteEntry = nil
w := httptest.NewRecorder()
ctx, cancel := context.WithTimeout(context.Background(), 3*time.Second)
defer cancel()
r := httptest.NewRequest(http.MethodGet, "/mybucket/dir/obj.bin", nil).WithContext(ctx)
err := s3a.streamFromVolumeServers(w, r, local, "", "mybucket", "dir/obj.bin", "")
require.Error(t, err)
assert.Equal(t, http.StatusInternalServerError, w.Code, "the status must not be committed before the first read succeeds")
assert.Contains(t, w.Body.String(), "InternalError")
assert.Nil(t, client.gotLoc, "an object that is not remote-mounted has no remote to fall back to")
})
t.Run("versioned read does not fall back to the unversioned remote key", func(t *testing.T) {
client := &fakeStreamRemoteClient{data: content}
remote_storage.RemoteStorageClientMakers["faketest"] = &fakeStreamRemoteMaker{client: client}
s3a := newLocalReadFallbackServer(t, startStreamThroughFiler(t, "faketest-cachedversioned", nil))
versioned := cachedEntry(content)
versioned.Extended = map[string][]byte{s3_constants.ExtVersionIdKey: []byte("v456")}
w := httptest.NewRecorder()
ctx, cancel := context.WithTimeout(context.Background(), 3*time.Second)
defer cancel()
r := httptest.NewRequest(http.MethodGet, "/mybucket/dir/obj.bin?versionId=v456", nil).WithContext(ctx)
err := s3a.streamFromVolumeServers(w, r, versioned, "", "mybucket", "dir/obj.bin", "v456")
require.Error(t, err)
assert.Nil(t, client.gotLoc, "a versioned read must not serve the unversioned remote object")
})
}
// the deferred status commit must be invisible on the success path: a readable
// local object still streams with the same status and headers as before
func TestS3LocalReadCommitsStatusOnFirstWrite(t *testing.T) {
content := []byte("0123456789")
newLocalServer := func(t *testing.T, name string) *S3ApiServer {
s3a := newLocalReadFallbackServer(t, startStreamThroughFiler(t, name, nil))
cache := chunk_cache.NewChunkCacheInMemory(16)
cache.SetChunk("1,0123456789ab", content)
s3a.readerCache = filer.NewReaderCache(8, cache, s3a.filerClient.GetLookupFileIdFunction(), s3a.filerClient)
return s3a
}
localEntry := func() *filer_pb.Entry {
local := cachedEntry(content)
local.RemoteEntry = nil
return local
}
t.Run("readable local object streams a 200", func(t *testing.T) {
s3a := newLocalServer(t, "faketest-localok")
w := httptest.NewRecorder()
r := httptest.NewRequest(http.MethodGet, "/mybucket/dir/obj.bin", nil)
err := s3a.streamFromVolumeServers(w, r, localEntry(), "", "mybucket", "dir/obj.bin", "")
require.NoError(t, err)
assert.Equal(t, http.StatusOK, w.Code)
assert.Equal(t, content, w.Body.Bytes())
assert.Equal(t, "10", w.Header().Get("Content-Length"))
})
t.Run("readable range streams a 206 with range headers", func(t *testing.T) {
s3a := newLocalServer(t, "faketest-localrange")
w := httptest.NewRecorder()
r := httptest.NewRequest(http.MethodGet, "/mybucket/dir/obj.bin", nil)
r.Header.Set("Range", "bytes=2-5")
err := s3a.streamFromVolumeServers(w, r, localEntry(), "", "mybucket", "dir/obj.bin", "")
require.NoError(t, err)
assert.Equal(t, http.StatusPartialContent, w.Code)
assert.Equal(t, content[2:6], w.Body.Bytes())
assert.Equal(t, "bytes 2-5/10", w.Header().Get("Content-Range"))
assert.Equal(t, "4", w.Header().Get("Content-Length"))
})
}
// a multi-chunk object whose later chunk's volume server is unreachable
type truncatedReaderAt struct {
data []byte
breakAt int64
err error
}
func (t truncatedReaderAt) ReadAt(p []byte, offset int64) (int, error) {
if offset >= t.breakAt {
return 0, t.err
}
return copy(p, t.data[offset:t.breakAt]), nil
}
// a client that disconnected mid-response
type failingWriter struct{ err error }
func (f failingWriter) Write(p []byte) (int, error) { return 0, f.err }
// the window the probe cannot cover: the byte at offset reads fine, the response
// is committed, and only then does a later chunk turn out to be unreadable
func TestStreamRangeToClientFinishesFromRemote(t *testing.T) {
content := []byte("0123456789")
size := int64(len(content))
newServer := func(t *testing.T, name string) (*S3ApiServer, *fakeStreamRemoteClient) {
client := &fakeStreamRemoteClient{data: content}
remote_storage.RemoteStorageClientMakers["faketest"] = &fakeStreamRemoteMaker{client: client}
return newLocalReadFallbackServer(t, startStreamThroughFiler(t, name, nil)), client
}
t.Run("later chunk failure is finished from the remote", func(t *testing.T) {
s3a, client := newServer(t, "faketest-midstream")
w := httptest.NewRecorder()
r := httptest.NewRequest(http.MethodGet, "/mybucket/dir/obj.bin", nil)
local := truncatedReaderAt{data: content, breakAt: 4, err: errors.New("volume: connection refused")}
written, err := s3a.streamRangeToClient(w, r, local, cachedEntry(content), "mybucket", "dir/obj.bin", 0, size, size, "")
require.NoError(t, err)
assert.Equal(t, size, written)
assert.Equal(t, content, w.Body.Bytes())
assert.Equal(t, int64(4), client.gotOffset, "the remote must resume where the local copy stopped")
assert.Equal(t, int64(6), client.gotSize)
})
t.Run("a short local read reported as clean EOF is not served truncated", func(t *testing.T) {
s3a, client := newServer(t, "faketest-shortread")
w := httptest.NewRecorder()
r := httptest.NewRequest(http.MethodGet, "/mybucket/dir/obj.bin", nil)
local := truncatedReaderAt{data: content, breakAt: 7, err: io.EOF}
written, err := s3a.streamRangeToClient(w, r, local, cachedEntry(content), "mybucket", "dir/obj.bin", 0, size, size, "")
require.NoError(t, err)
assert.Equal(t, size, written)
assert.Equal(t, content, w.Body.Bytes())
assert.Equal(t, int64(7), client.gotOffset)
})
t.Run("range read resumes at the absolute offset", func(t *testing.T) {
s3a, client := newServer(t, "faketest-midstreamrange")
w := httptest.NewRecorder()
r := httptest.NewRequest(http.MethodGet, "/mybucket/dir/obj.bin", nil)
local := truncatedReaderAt{data: content, breakAt: 5, err: errors.New("volume: connection refused")}
written, err := s3a.streamRangeToClient(w, r, local, cachedEntry(content), "mybucket", "dir/obj.bin", 2, 6, size, "")
require.NoError(t, err)
assert.Equal(t, int64(6), written)
assert.Equal(t, content[2:8], w.Body.Bytes())
assert.Equal(t, int64(5), client.gotOffset)
assert.Equal(t, int64(3), client.gotSize)
})
t.Run("a remote overwritten since caching is not spliced onto the local prefix", func(t *testing.T) {
s3a, client := newServer(t, "faketest-midstreamchanged")
client.stat = &filer_pb.RemoteEntry{RemoteSize: size, RemoteETag: "reuploaded"}
w := httptest.NewRecorder()
r := httptest.NewRequest(http.MethodGet, "/mybucket/dir/obj.bin", nil)
boom := errors.New("volume: connection refused")
written, err := s3a.streamRangeToClient(w, r, truncatedReaderAt{data: content, breakAt: 4, err: boom}, cachedEntry(content), "mybucket", "dir/obj.bin", 0, size, size, "")
require.Error(t, err)
assert.Equal(t, int64(4), written, "a truncated body beats one mixing two generations")
assert.Nil(t, client.gotLoc, "must not read a remote that no longer matches what was cached")
})
t.Run("a local-only object keeps the mid-stream error", func(t *testing.T) {
s3a, client := newServer(t, "faketest-midstreamlocal")
local := cachedEntry(content)
local.RemoteEntry = nil
w := httptest.NewRecorder()
r := httptest.NewRequest(http.MethodGet, "/mybucket/dir/obj.bin", nil)
boom := errors.New("volume: connection refused")
written, err := s3a.streamRangeToClient(w, r, truncatedReaderAt{data: content, breakAt: 4, err: boom}, local, "mybucket", "dir/obj.bin", 0, size, size, "")
assert.ErrorIs(t, err, boom)
assert.Equal(t, int64(4), written)
assert.Nil(t, client.gotLoc, "an object that is not remote-mounted has no remote to fall back to")
})
t.Run("a failed write to the client is not refetched from the remote", func(t *testing.T) {
s3a, client := newServer(t, "faketest-midstreamwrite")
r := httptest.NewRequest(http.MethodGet, "/mybucket/dir/obj.bin", nil)
broken := errors.New("write: broken pipe")
written, err := s3a.streamRangeToClient(failingWriter{err: broken}, r, bytes.NewReader(content), cachedEntry(content), "mybucket", "dir/obj.bin", 0, size, size, "")
assert.ErrorIs(t, err, broken)
assert.Zero(t, written)
assert.Nil(t, client.gotLoc, "the client is gone; refetching from the remote is wasted work")
})
}