Truncate segments on broken header

util_test.go

@@ -0,0 +1,67 @@
+// The MIT License (MIT)
+
+// Copyright (c) 2014 Ben Johnson
+
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+package tsdb
+
+import (
+	"fmt"
+	"path/filepath"
+	"reflect"
+	"runtime"
+	"testing"
+)
+
+// Assert fails the test if the condition is false.
+func Assert(tb testing.TB, condition bool, msg string, v ...interface{}) {
+	if !condition {
+		_, file, line, _ := runtime.Caller(1)
+		fmt.Printf("\033[31m%s:%d: "+msg+"\033[39m\n\n", append([]interface{}{filepath.Base(file), line}, v...)...)
+		tb.FailNow()
+	}
+}
+
+// Ok fails the test if an err is not nil.
+func Ok(tb testing.TB, err error) {
+	if err != nil {
+		_, file, line, _ := runtime.Caller(1)
+		fmt.Printf("\033[31m%s:%d: unexpected error: %s\033[39m\n\n", filepath.Base(file), line, err.Error())
+		tb.FailNow()
+	}
+}
+
+// NotOk fails the test if an err is nil.
+func NotOk(tb testing.TB, err error) {
+	if err == nil {
+		_, file, line, _ := runtime.Caller(1)
+		fmt.Printf("\033[31m%s:%d: expected error, got nothing \033[39m\n\n", filepath.Base(file), line)
+		tb.FailNow()
+	}
+}
+
+// Equals fails the test if exp is not equal to act.
+func Equals(tb testing.TB, exp, act interface{}) {
+	if !reflect.DeepEqual(exp, act) {
+		_, file, line, _ := runtime.Caller(1)
+		fmt.Printf("\033[31m%s:%d:\n\n\texp: %#v\n\n\tgot: %#v\033[39m\n\n", filepath.Base(file), line, exp, act)
+		tb.FailNow()
+	}
+}

wal.go

@@ -222,12 +222,21 @@ func OpenSegmentWAL(dir string, logger log.Logger, flushInterval time.Duration,
 	if err != nil {
 		return nil, err
 	}
-	for _, fn := range fns {
+
+	for i, fn := range fns {
 		f, err := w.openSegmentFile(fn)
-		if err != nil {
-			return nil, err
-		}
+		if err == nil {
 			w.files = append(w.files, newSegmentFile(f))
+			continue
+		}
+		level.Warn(logger).Log("msg", "invalid segment file detected, truncating WAL", "err", err, "file", fn)
+
+		for _, fn := range fns[i:] {
+			if err := os.Remove(fn); err != nil {
+				return w, errors.Wrap(err, "removing segment failed")
+			}
+		}
+		break
 	}
 
 	go w.run(flushInterval)

wal_test.go

@@ -15,69 +15,16 @@ package tsdb
 
 import (
 	"encoding/binary"
-	"fmt"
 	"io/ioutil"
 	"math/rand"
 	"os"
 	"testing"
 
 	"github.com/go-kit/kit/log"
+	"github.com/prometheus/tsdb/fileutil"
 	"github.com/stretchr/testify/require"
 )
 
-func TestSegmentWAL_Open(t *testing.T) {
-	tmpdir, err := ioutil.TempDir("", "test_wal_open")
-	require.NoError(t, err)
-	defer os.RemoveAll(tmpdir)
-
-	// Create segment files with an appropriate header.
-	for i := 1; i <= 5; i++ {
-		metab := make([]byte, 8)
-		binary.BigEndian.PutUint32(metab[:4], WALMagic)
-		metab[4] = WALFormatDefault
-
-		f, err := os.Create(fmt.Sprintf("%s/000%d", tmpdir, i))
-		require.NoError(t, err)
-		_, err = f.Write(metab)
-		require.NoError(t, err)
-		require.NoError(t, f.Close())
-	}
-
-	// Initialize 5 correct segment files.
-	w, err := OpenSegmentWAL(tmpdir, nil, 0, nil)
-	require.NoError(t, err)
-
-	require.Equal(t, 5, len(w.files), "unexpected number of segments loaded")
-
-	// Validate that files are locked properly.
-	for _, of := range w.files {
-		f, err := os.Open(of.Name())
-		require.NoError(t, err, "open locked segment %s", f.Name())
-
-		_, err = f.Read([]byte{0})
-		require.NoError(t, err, "read locked segment %s", f.Name())
-
-		_, err = f.Write([]byte{0})
-		require.Error(t, err, "write to tail segment file %s", f.Name())
-
-		require.NoError(t, f.Close())
-	}
-
-	for _, f := range w.files {
-		require.NoError(t, f.Close())
-	}
-
-	// Make initialization fail by corrupting the header of one file.
-	f, err := os.OpenFile(w.files[3].Name(), os.O_WRONLY, 0666)
-	require.NoError(t, err)
-
-	_, err = f.WriteAt([]byte{0}, 4)
-	require.NoError(t, err)
-
-	w, err = OpenSegmentWAL(tmpdir, nil, 0, nil)
-	require.Error(t, err, "open with corrupted segments")
-}
-
 func TestSegmentWAL_cut(t *testing.T) {
 	tmpdir, err := ioutil.TempDir("", "test_wal_cut")
 	require.NoError(t, err)
@@ -312,6 +259,36 @@ func TestSegmentWAL_Log_Restore(t *testing.T) {
 	}
 }
 
+func TestWALRestoreCorrupted_invalidSegment(t *testing.T) {
+	dir, err := ioutil.TempDir("", "test_wal_log_restore")
+	Ok(t, err)
+	defer os.RemoveAll(dir)
+
+	wal, err := OpenSegmentWAL(dir, nil, 0, nil)
+	Ok(t, err)
+
+	_, err = wal.createSegmentFile(dir + "/000000")
+	Ok(t, err)
+	f, err := wal.createSegmentFile(dir + "/000001")
+	Ok(t, err)
+	_, err = wal.createSegmentFile(dir + "/000002")
+	Ok(t, err)
+
+	// Make header of second segment invalid.
+	_, err = f.WriteAt([]byte{1, 2, 3, 4}, 0)
+	Ok(t, err)
+	Ok(t, f.Close())
+
+	Ok(t, wal.Close())
+
+	wal, err = OpenSegmentWAL(dir, log.NewLogfmtLogger(os.Stderr), 0, nil)
+	Ok(t, err)
+
+	fns, err := fileutil.ReadDir(dir)
+	Ok(t, err)
+	Equals(t, []string{"000000"}, fns)
+}
+
 // Test reading from a WAL that has been corrupted through various means.
 func TestWALRestoreCorrupted(t *testing.T) {
 	cases := []struct {