func TestAtomicUpdateNoChange(t *testing.T) {
fakeClient := NewFakeEtcdClient(t)
fakeClient.TestIndex = true
helper := EtcdHelper{fakeClient, scheme, api.NewJSONBaseResourceVersioner()}
// Create a new node.
fakeClient.ExpectNotFoundGet("/some/key")
obj := &TestResource{JSONBase: api.JSONBase{ID: "foo"}, Value: 1}
err := helper.AtomicUpdate("/some/key", &TestResource{}, func(in interface{}) (interface{}, error) {
return obj, nil
})
if err != nil {
t.Errorf("Unexpected error %#v", err)
}
// Update an existing node with the same data
callbackCalled := false
objUpdate := &TestResource{JSONBase: api.JSONBase{ID: "foo"}, Value: 1}
fakeClient.Err = errors.New("should not be called")
err = helper.AtomicUpdate("/some/key", &TestResource{}, func(in interface{}) (interface{}, error) {
callbackCalled = true
return objUpdate, nil
})
if err != nil {
t.Errorf("Unexpected error %#v", err)
}
if !callbackCalled {
t.Errorf("tryUpdate callback should have been called.")
}
}
func TestAtomicUpdate(t *testing.T) {
fakeClient := NewFakeEtcdClient(t)
fakeClient.TestIndex = true
codec := scheme
helper := EtcdHelper{fakeClient, codec, api.NewJSONBaseResourceVersioner()}
// Create a new node.
fakeClient.ExpectNotFoundGet("/some/key")
obj := &TestResource{JSONBase: api.JSONBase{ID: "foo"}, Value: 1}
err := helper.AtomicUpdate("/some/key", &TestResource{}, func(in interface{}) (interface{}, error) {
return obj, nil
})
if err != nil {
t.Errorf("Unexpected error %#v", err)
}
data, err := codec.Encode(obj)
if err != nil {
t.Errorf("Unexpected error %#v", err)
}
expect := string(data)
got := fakeClient.Data["/some/key"].R.Node.Value
if expect != got {
t.Errorf("Wanted %v, got %v", expect, got)
}
// Update an existing node.
callbackCalled := false
objUpdate := &TestResource{JSONBase: api.JSONBase{ID: "foo"}, Value: 2}
err = helper.AtomicUpdate("/some/key", &TestResource{}, func(in interface{}) (interface{}, error) {
callbackCalled = true
if in.(*TestResource).Value != 1 {
t.Errorf("Callback input was not current set value")
}
return objUpdate, nil
})
if err != nil {
t.Errorf("Unexpected error %#v", err)
}
data, err = codec.Encode(objUpdate)
if err != nil {
t.Errorf("Unexpected error %#v", err)
}
expect = string(data)
got = fakeClient.Data["/some/key"].R.Node.Value
if expect != got {
t.Errorf("Wanted %v, got %v", expect, got)
}
if !callbackCalled {
t.Errorf("tryUpdate callback should have been called.")
}
}
func TestAtomicUpdate_CreateCollision(t *testing.T) {
fakeClient := NewFakeEtcdClient(t)
fakeClient.TestIndex = true
codec := scheme
helper := EtcdHelper{fakeClient, codec, api.NewJSONBaseResourceVersioner()}
fakeClient.ExpectNotFoundGet("/some/key")
const concurrency = 10
var wgDone sync.WaitGroup
var wgForceCollision sync.WaitGroup
wgDone.Add(concurrency)
wgForceCollision.Add(concurrency)
for i := 0; i < concurrency; i++ {
// Increment TestResource.Value by 1
go func() {
defer wgDone.Done()
firstCall := true
err := helper.AtomicUpdate("/some/key", &TestResource{}, func(in interface{}) (interface{}, error) {
defer func() { firstCall = false }()
if firstCall {
// Force collision by joining all concurrent AtomicUpdate operations here.
wgForceCollision.Done()
wgForceCollision.Wait()
}
currValue := in.(*TestResource).Value
obj := TestResource{JSONBase: api.JSONBase{ID: "foo"}, Value: currValue + 1}
return obj, nil
})
if err != nil {
t.Errorf("Unexpected error %#v", err)
}
}()
}
wgDone.Wait()
// Check that stored TestResource has received all updates.
body := fakeClient.Data["/some/key"].R.Node.Value
stored := &TestResource{}
if err := codec.DecodeInto([]byte(body), stored); err != nil {
t.Errorf("Error decoding stored value: %v", body)
}
if stored.Value != concurrency {
t.Errorf("Some of the writes were lost. Stored value: %d", stored.Value)
}
}