/// <summary>
/// Connect to canal server.
/// </summary>
/// <returns></returns>
public async Task ConnectAsync()
{
//get canal address from zk
await ConnectToZkAsync();
var nodeData = await _zk.GetDataAsync(ZK_SERVER_RUNNING_NODE);
var runningInfo = JsonConvert.DeserializeObject <CanalServerRunningInfo>(Encoding.UTF8.GetString(nodeData));
_logger.LogInformation($"get canal address from zookeeper success: {runningInfo.Address}");
//connect to canal
_currentConn = new SimpleCanalConnection(CopyOptions(runningInfo), _loggerFactory.CreateLogger <SimpleCanalConnection>());
await _currentConn.ConnectAsync();
_serverRunningNodeReCreated = false;
var localIp = _currentConn.GetLocalEndPoint().ToString();
_clientRunningInfo = new CanalClientRunningInfo()
{
Active = true, Address = localIp, ClientId = _options.ClientId
};
_ = GetZkLockAsync(_clientRunningInfo);
await _completionSource.Task;
_logger.LogInformation("Ready to use!");
}
private async Task GetZkLockAsync(CanalClientRunningInfo runningInfo, bool waiting = false)
{
var times = 0;
while (waiting && times < 60)
{
await Task.Delay(1000);
times++;
_logger.LogWarning($"Waiting for get lock {times}-60...");
}
if (await _zk.NodeExistsAsync(ZK_CLIENT_RUNNING_NODE))
{
_logger.LogInformation($"Node {ZK_CLIENT_RUNNING_NODE} exits, get Zookeeper lock failed. Other instances are running.");
_logger.LogWarning("Waiting...");
}
else
{
try
{
var clientNodeData = Encoding.UTF8.GetBytes(JsonConvert.SerializeObject(runningInfo));
var parentNode = ZK_CLIENT_RUNNING_NODE.Replace("/running", "");
if (!await _zk.NodeExistsAsync(parentNode))
{
await _zk.CreateNodeAsync(parentNode, null,
new List <Acl>() { new Acl(AclPerm.All, AclScheme.World, AclId.World()) }, NodeType.Persistent);
}
await _zk.CreateNodeAsync(ZK_CLIENT_RUNNING_NODE, clientNodeData,
new List <Acl>() { new Acl(AclPerm.All, AclScheme.World, AclId.World()) }, NodeType.Ephemeral);
await _zk.CreateNodeAsync(parentNode + "/" + runningInfo.Address, null,
new List <Acl>() { new Acl(AclPerm.All, AclScheme.World, AclId.World()) }, NodeType.Ephemeral);
await _zk.NodeExistsAsync(ZK_CLIENT_RUNNING_NODE);
_completionSource.SetResult(0);
_logger.LogInformation("Get zookeeper lock success.");
}
catch (KeeperException.NodeExistsException e)
{
if (e.getPath() != ZK_CLIENT_RUNNING_NODE)
{
_logger.LogError(e, "Error during get lock.");
Environment.Exit(-1);
}
_logger.LogInformation(
$"Node {ZK_CLIENT_RUNNING_NODE} exits, get Zookeeper lock failed. Other instances are running.");
_logger.LogWarning("Waiting...");
}
catch (Exception e)
{
_logger.LogError(e, "Exception in lock");
}
}
}