public void UpdateData_should_return_fail_without_retries_if_cant_read_data(ZooKeeperStatus errorStatus)
{
const string path = "zk/default";
zooKeeperClient.GetDataAsync(Arg.Any <GetDataRequest>()).Returns(GetDataResult.Unsuccessful(errorStatus, path, null));
zooKeeperClient.UpdateData(new UpdateDataRequest(path, dummyUpdate))
.Should()
.BeEquivalentTo(UpdateDataResult.Unsuccessful(errorStatus, path, null));
zooKeeperClient.ReceivedWithAnyArgs(1)
.GetDataAsync(Arg.Any <GetDataRequest>());
zooKeeperClient.DidNotReceiveWithAnyArgs()
.SetDataAsync(Arg.Any <SetDataRequest>());
}
public void UpdateData_should_return_false_after_one_attempt_if_set_data_fails(ZooKeeperStatus failFastStatus)
{
const string path = "zk/default";
var bytes = new byte[] { 0, 1, 1, 2, 3, 5, 8, 13 };
zooKeeperClient.GetDataAsync(Arg.Any <GetDataRequest>())
.Returns(GetDataResult.Successful(path, bytes, Stat));
zooKeeperClient.SetDataAsync(Arg.Any <SetDataRequest>())
.Returns(SetDataResult.Unsuccessful(failFastStatus, path, null));
zooKeeperClient.UpdateData(new UpdateDataRequest(path, dummyUpdate))
.Should()
.BeEquivalentTo(UpdateDataResult.Unsuccessful(failFastStatus, path, null));
zooKeeperClient.ReceivedWithAnyArgs(1).SetDataAsync(Arg.Any <SetDataRequest>());
}
/// <summary>
/// <para>Trying to update node data with optimistic concurrency strategy according to given <paramref name="request"/>.</para>
/// <para>Check returned <see cref="UpdateDataResult"/> to see if operation was successful.</para>
/// </summary>
public static async Task <UpdateDataResult> UpdateDataAsync(this IZooKeeperClient zooKeeperClient, UpdateDataRequest request)
{
try
{
for (var i = 0; i < request.Attempts; i++)
{
var readResult = await zooKeeperClient.GetDataAsync(new GetDataRequest(request.Path)).ConfigureAwait(false);
if (!readResult.IsSuccessful)
{
return(UpdateDataResult.Unsuccessful(readResult.Status, readResult.Path, readResult.Exception));
}
var newData = request.Update(readResult.Data);
if (ByteArrayKey.Equals(readResult.Data, newData))
{
return(UpdateDataResult.Successful(readResult.Path));
}
var setDataRequest = new SetDataRequest(request.Path, newData)
{
Version = readResult.Stat.Version
};
var updateResult = await zooKeeperClient.SetDataAsync(setDataRequest).ConfigureAwait(false);
if (updateResult.Status == ZooKeeperStatus.VersionsMismatch)
{
continue;
}
return(updateResult.IsSuccessful ? UpdateDataResult.Successful(updateResult.Path) : UpdateDataResult.Unsuccessful(updateResult.Status, updateResult.Path, updateResult.Exception));
}
return(UpdateDataResult.Unsuccessful(ZooKeeperStatus.VersionsMismatch, request.Path, null));
}
catch (Exception e)
{
return(UpdateDataResult.Unsuccessful(ZooKeeperStatus.UnknownError, request.Path, e));
}
}
public void UpdateData_should_make_all_attempts_to_set_data_and_return_fail()
{
const string path = "zk/default";
const int attempts = 10;
var bytes = new byte[] { 0, 1, 1, 2, 3, 5, 8, 13 };
zooKeeperClient.GetDataAsync(Arg.Any <GetDataRequest>())
.Returns(GetDataResult.Successful(path, bytes, Stat));
zooKeeperClient.SetDataAsync(Arg.Any <SetDataRequest>())
.Returns(SetDataResult.Unsuccessful(ZooKeeperStatus.VersionsMismatch, path, null));
zooKeeperClient.UpdateData(new UpdateDataRequest(path, dummyUpdate)
{
Attempts = attempts
})
.Should()
.BeEquivalentTo(UpdateDataResult.Unsuccessful(ZooKeeperStatus.VersionsMismatch, path, null));
zooKeeperClient.ReceivedWithAnyArgs(attempts)
.SetDataAsync(Arg.Any <SetDataRequest>());
}