// 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)
disableOwnNodeCertain(s)
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 := roachpb.Key("key")
value := roachpb.Value{}
// 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) *roachpb.Error {
i++
s.Manual.Increment(1)
futureTS := s.Clock.Now()
futureTS.WallTime++
value.SetBytes([]byte(fmt.Sprintf("value-%d", i)))
if err := engine.MVCCPut(s.Eng, nil, key, futureTS, value, nil); err != nil {
t.Fatal(err)
}
gr, pErr := txn.Get(key)
if pErr != nil {
return pErr
}
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 roachpb.Value initialized from the source
// interface{}, returning an error if the types are not compatible.
func marshalValue(v interface{}) (roachpb.Value, error) {
var r roachpb.Value
// Handle a few common types via a type switch.
switch t := v.(type) {
case *roachpb.Value:
return *t, nil
case nil:
return r, nil
case bool:
i := int64(0)
if t {
i = 1
}
r.SetInt(i)
return r, nil
case string:
r.SetBytes([]byte(t))
return r, nil
case []byte:
r.SetBytes(t)
return r, nil
case inf.Dec:
err := r.SetDecimal(&t)
return r, err
case roachpb.Key:
r.SetBytes([]byte(t))
return r, nil
case time.Time:
r.SetTime(t)
return r, nil
case duration.Duration:
err := r.SetDuration(t)
return r, err
case proto.Message:
err := r.SetProto(t)
return r, err
}
// Handle all of the Go primitive types besides struct and pointers. This
// switch also handles types based on a primitive type (e.g. "type MyInt
// int").
switch v := reflect.ValueOf(v); v.Kind() {
case reflect.Bool:
i := int64(0)
if v.Bool() {
i = 1
}
r.SetInt(i)
return r, nil
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
r.SetInt(v.Int())
return r, nil
case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
r.SetInt(int64(v.Uint()))
return r, nil
case reflect.Float32, reflect.Float64:
r.SetFloat(v.Float())
return r, nil
case reflect.String:
r.SetBytes([]byte(v.String()))
return r, nil
}
return r, fmt.Errorf("unable to marshal %T: %v", v, v)
}