// Indirectly this tests that the transaction remembers the NodeID of the node
// being read from correctly, at least in this simple case. Not remembering the
// node would lead to thousands of transaction restarts and almost certainly a
// test timeout.
func TestUncertaintyRestarts(t *testing.T) {
{
db, eng, clock, mClock, _, transport, err := createTestDB()
if err != nil {
t.Fatal(err)
}
defer transport.Close()
// Set a large offset so that a busy restart-loop
// really shows. Also makes sure that the values
// we write in the future below don't actually
// wind up in the past.
offset := 4000 * time.Millisecond
clock.SetMaxOffset(offset)
key := proto.Key("key")
value := proto.Value{
Bytes: nil, // Set for each Put
}
// With the correct restart behaviour, we see only one restart
// and the value read is the very first one (as nothing else
// has been written)
wantedBytes := []byte("value-0")
txnOpts := &client.TransactionOptions{
Name: "uncertainty",
}
gr := &proto.GetResponse{}
i := -1
tErr := db.RunTransaction(txnOpts, func(txn *client.KV) error {
i++
mClock.Increment(1)
futureTS := clock.Now()
futureTS.WallTime++
value.Bytes = []byte(fmt.Sprintf("value-%d", i))
err = engine.MVCCPut(eng, nil, key, futureTS, value, nil)
if err != nil {
t.Fatal(err)
}
gr.Reset()
if err := txn.Call(proto.Get, proto.GetArgs(key), gr); err != nil {
return err
}
if gr.Value == nil || !bytes.Equal(gr.Value.Bytes, wantedBytes) {
t.Fatalf("%d: read wrong value: %v, wanted %q", i,
gr.Value, wantedBytes)
}
return nil
})
if i != 1 {
t.Errorf("txn restarted %d times, expected only one restart", i)
}
if tErr != nil {
t.Fatal(tErr)
}
}
}
// Indirectly this tests that the transaction remembers the NodeID of the node
// being read from correctly, at least in this simple case. Not remembering the
// node would lead to thousands of transaction restarts and almost certainly a
// test timeout.
func TestUncertaintyRestarts(t *testing.T) {
defer leaktest.AfterTest(t)
s := createTestDB(t)
defer s.Stop()
// Set a large offset so that a busy restart-loop
// really shows. Also makes sure that the values
// we write in the future below don't actually
// wind up in the past.
offset := 4000 * time.Millisecond
s.Clock.SetMaxOffset(offset)
key := proto.Key("key")
value := proto.Value{
Bytes: nil, // Set for each Put
}
// With the correct restart behaviour, we see only one restart
// and the value read is the very first one (as nothing else
// has been written)
wantedBytes := []byte("value-0")
i := -1
tErr := s.DB.Txn(func(txn *client.Txn) error {
i++
s.Manual.Increment(1)
futureTS := s.Clock.Now()
futureTS.WallTime++
value.Bytes = []byte(fmt.Sprintf("value-%d", i))
if err := engine.MVCCPut(s.Eng, nil, key, futureTS, value, nil); err != nil {
t.Fatal(err)
}
gr, err := txn.Get(key)
if err != nil {
return err
}
if !gr.Exists() || !bytes.Equal(gr.ValueBytes(), wantedBytes) {
t.Fatalf("%d: read wrong value: %v, wanted %q", i, gr.Value, wantedBytes)
}
return nil
})
if i != 1 {
t.Errorf("txn restarted %d times, expected only one restart", i)
}
if tErr != nil {
t.Fatal(tErr)
}
}
// marshalValue returns a proto.Value initialized from the source
// reflect.Value, returning an error if the types are not compatible.
func marshalValue(v reflect.Value) (proto.Value, error) {
var r proto.Value
if !v.IsValid() {
return r, nil
}
switch t := v.Interface().(type) {
case nil:
return r, nil
case string:
r.Bytes = []byte(t)
return r, nil
case []byte:
r.Bytes = t
return r, nil
case proto.Key:
r.Bytes = []byte(t)
return r, nil
case gogoproto.Message:
var err error
r.Bytes, err = gogoproto.Marshal(t)
return r, err
case encoding.BinaryMarshaler:
var err error
r.Bytes, err = t.MarshalBinary()
return r, err
}
switch v.Kind() {
case reflect.Bool:
i := int64(0)
if v.Bool() {
i = 1
}
r.SetInteger(i)
return r, nil
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
r.SetInteger(v.Int())
return r, nil
case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
r.SetInteger(int64(v.Uint()))
return r, nil
case reflect.Float32, reflect.Float64:
r.SetInteger(int64(math.Float64bits(v.Float())))
return r, nil
case reflect.String:
r.Bytes = []byte(v.String())
return r, nil
}
return r, fmt.Errorf("unable to marshal value: %s", v)
}