private async Task <bool> CheckPersistToAsync(ObserveParams observeParams)
{
if (observeParams.PersistTo == PersistTo.Zero)
{
return(true);
}
var op = new ObserveSeqno(observeParams.Token, _clusterController.Transcoder, _timeout);
observeParams.Operation = op;
var tcs = new TaskCompletionSource <IOperationResult <ObserveSeqnoResponse> >();
op.Completed = CallbackFactory.CompletedFuncForRetry(_pending, _clusterController, tcs);
_pending.TryAdd(op.Opaque, op);
var server = await GetServerAsync(observeParams);
await server.SendAsync(op).ContinueOnAnyContext();
var response = await tcs.Task.ContinueOnAnyContext();
observeParams.CheckMutationLost(response);
observeParams.CheckPersisted(response);
return(observeParams.IsDurabilityMet());
}
static Task <bool> CheckReplicaAsync(ObserveParams observeParams, ObserveSeqno op, int replicaId)
{
var cloned = (ObserveSeqno)op.Clone();
var replica = observeParams.VBucket.LocateReplica(replicaId);
var result = replica.Send(cloned);
observeParams.CheckMutationLost(result.Value);
observeParams.CheckPersisted(result.Value);
observeParams.CheckReplicated(result.Value);
return(Task.FromResult(observeParams.IsDurabilityMet()));
}
async Task <bool> CheckReplicasAsync(ObserveParams observeParams, ObserveSeqno op)
{
var replicas = observeParams.GetReplicas();
var tasks = new List <Task <bool> >();
replicas.ForEach(x => tasks.Add(CheckReplicaAsync(observeParams, op, x)));
await Task.WhenAll(tasks);
return(observeParams.IsDurabilityMet());
}
/// <summary>
/// Checks a replica for durability constraints.
/// </summary>
/// <param name="observeParams">The observe parameters.</param>
/// <param name="op">The op.</param>
/// <param name="replicaId">The replica identifier.</param>
/// <returns></returns>
private bool CheckReplica(ObserveParams observeParams, ObserveSeqno op, int replicaId)
{
var cloned = (ObserveSeqno)op.Clone();
var replica = observeParams.VBucket.LocateReplica(replicaId);
var result = replica.Send(cloned);
observeParams.CheckMutationLost(result);
observeParams.CheckPersisted(result);
observeParams.CheckReplicated(result);
return(observeParams.IsDurabilityMet());
}
/// <summary>
/// Performs an observe event on the durability requirements specified on a key asynchronously
/// </summary>
/// <param name="token">The <see cref="MutationToken"/> to compare against.</param>
/// <param name="replicateTo">The number of replicas that the key must be replicated to to satisfy the durability constraint.</param>
/// <param name="persistTo">The number of replicas that the key must be persisted to to satisfy the durability constraint.</param>
/// <returns> A <see cref="Task{bool}"/> representing the aynchronous operation.</returns>
/// <exception cref="ReplicaNotConfiguredException">Thrown if the number of replicas requested
/// in the ReplicateTo parameter does not match the # of replicas configured on the server.</exception>
public async Task <bool> ObserveAsync(MutationToken token, ReplicateTo replicateTo, PersistTo persistTo)
{
var keyMapper = (VBucketKeyMapper)_configInfo.GetKeyMapper();
var obParams = new ObserveParams
{
ReplicateTo = replicateTo,
PersistTo = persistTo,
Token = token,
VBucket = keyMapper[token.VBucketId]
};
obParams.CheckConfiguredReplicas();
var op = new ObserveSeqno(obParams.Token, _transcoder, _timeout);
using (var cts = new CancellationTokenSource((int)_timeout))
{
//perform the observe operation at the set interval and terminate if not successful by the timeout
var task = await ObserveEvery(async p =>
{
IServer master;
var attempts = 0;
while ((master = p.VBucket.LocatePrimary()) == null)
{
if (attempts++ > 10)
{
throw new TimeoutException("Could not acquire a server.");
}
await Task.Delay((int)Math.Pow(2, attempts)).ContinueOnAnyContext();
}
var result = master.Send(op);
var osr = result.Value;
p.CheckMutationLost(osr);
p.CheckPersisted(osr);
if (p.IsDurabilityMet())
{
return(true);
}
return(await CheckReplicasAsync(p, op).ContinueOnAnyContext());
}, obParams, _interval, op, cts.Token).ContinueOnAnyContext();
return(task);
}
}
/// <summary>
/// Observes the specified key using the Seqno.
/// </summary>
/// <param name="key">The key.</param>
/// <param name="token">The token.</param>
/// <param name="replicateTo">The replicate to.</param>
/// <param name="persistTo">The persist to.</param>
/// <returns>True if durability constraints were matched.</returns>
/// <exception cref="DocumentMutationLostException">Thrown if the observed document was lost during
/// a hard failover because the document did not reach the replica in time.</exception>
/// <exception cref="ReplicaNotConfiguredException">Thrown if the number of replicas requested
/// in the ReplicateTo parameter does not match the # of replicas configured on the server.</exception>
public bool Observe(MutationToken token, ReplicateTo replicateTo, PersistTo persistTo)
{
var keyMapper = (VBucketKeyMapper)_configInfo.GetKeyMapper();
var p = new ObserveParams
{
ReplicateTo = replicateTo,
PersistTo = persistTo,
Token = token,
VBucket = keyMapper[token.VBucketId]
};
p.CheckConfiguredReplicas();
var op = new ObserveSeqno(p.Token, _transcoder, _timeout);
do
{
var master = p.VBucket.LocatePrimary();
var result = master.Send(op);
var osr = result.Value;
p.CheckMutationLost(osr);
p.CheckPersisted(osr);
if (p.IsDurabilityMet())
{
return(true);
}
if (CheckReplicas(p, op))
{
return(true);
}
//prepare for another attempt
op = (ObserveSeqno)op.Clone();
p.Reset();
} while (!op.TimedOut());
return(false);
}
public void Test_ObserveSeqno2()
{
var key = "bar";
var delete = new Delete(key, GetVBucket(), Transcoder, OperationLifespanTimeout);
var deleteResult = IOService.Execute(delete);
var features = new List<short>();
features.Add((short)ServerFeatures.MutationSeqno);
var hello = new Hello("couchbase-net-sdk/2.1.4", features.ToArray(), Transcoder, 0, 0);
var result = IOService.Execute(hello);
Assert.IsTrue(result.Success);
var add = new Add<string>(key, "foo", GetVBucket(), Transcoder, OperationLifespanTimeout);
var result2 = IOService.Execute(add);
var observeSeqno = new ObserveSeqno(result2.Token, Transcoder, 1000);
var observeSeqnoResult = IOService.Execute(observeSeqno);
Assert.IsTrue(observeSeqnoResult.Success);
}
private async Task <bool> CheckReplicaAsync(ObserveParams observeParams, int replicaId)
{
var op = new ObserveSeqno(observeParams.Token, _clusterController.Transcoder, _timeout);
observeParams.Operation = op;
var tcs = new TaskCompletionSource <IOperationResult <ObserveSeqnoResponse> >();
op.Completed = CallbackFactory.CompletedFuncForRetry(_pending, _clusterController, tcs);
_pending.TryAdd(op.Opaque, op);
Log.Debug("checking replica {0} - opaque: {1}", replicaId, op.Opaque);
var replica = observeParams.VBucket.LocateReplica(replicaId);
await replica.SendAsync(op).ContinueOnAnyContext();
var response = await tcs.Task.ContinueOnAnyContext();
observeParams.CheckMutationLost(response);
observeParams.CheckPersisted(response);
observeParams.CheckReplicated(response);
return(observeParams.IsDurabilityMet());
}
public void Test_ObserveSeqno2()
{
var key = "bar";
var delete = new Delete(key, GetVBucket(), Transcoder, OperationLifespanTimeout);
var deleteResult = IOStrategy.Execute(delete);
var features = new List <short>();
features.Add((short)ServerFeatures.MutationSeqno);
var hello = new Hello("couchbase-net-sdk/2.1.4", features.ToArray(), Transcoder, 0, 0);
var result = IOStrategy.Execute(hello);
Assert.IsTrue(result.Success);
var add = new Add <string>(key, "foo", GetVBucket(), Transcoder, OperationLifespanTimeout);
var result2 = IOStrategy.Execute(add);
var observeSeqno = new ObserveSeqno(result2.Token, Transcoder, 1000);
var observeSeqnoResult = IOStrategy.Execute(observeSeqno);
Assert.IsTrue(observeSeqnoResult.Success);
}
/// <summary>
/// Observes a set of keys at a specified interval and timeout.
/// </summary>
/// <param name="observe">The func to call at the specific interval</param>
/// <param name="observeParams">The parameters to pass in.</param>
/// <param name="interval">The interval to check.</param>
/// <param name="cancellationToken">The <see cref="CancellationToken"/> to use to terminate the observation at the specified timeout.</param>
/// <returns>True if the durability requirements specified by <see cref="PersistTo"/> and <see cref="ReplicateTo"/> have been satisfied.</returns>
static async Task<bool> ObserveEvery(Func<ObserveParams, Task<bool>> observe, ObserveParams observeParams, int interval, ObserveSeqno op, CancellationToken cancellationToken)
{
while (true)
{
var result = await observe(observeParams).ContinueOnAnyContext();
if (result)
{
return true;
}
var task = Task.Delay(interval, cancellationToken).ContinueOnAnyContext();
try
{
await task;
}
catch (TaskCanceledException)
{
return false;
}
//prepare for a second attempt
op = (ObserveSeqno)op.Clone();
observeParams.Reset();
}
}
/// <summary>
/// Performs an observe event on the durability requirements specified on a key asynchronously
/// </summary>
/// <param name="token">The <see cref="MutationToken"/> to compare against.</param>
/// <param name="replicateTo">The number of replicas that the key must be replicated to to satisfy the durability constraint.</param>
/// <param name="persistTo">The number of replicas that the key must be persisted to to satisfy the durability constraint.</param>
/// <returns> A <see cref="Task{bool}"/> representing the aynchronous operation.</returns>
/// <exception cref="ReplicaNotConfiguredException">Thrown if the number of replicas requested
/// in the ReplicateTo parameter does not match the # of replicas configured on the server.</exception>
public async Task<bool> ObserveAsync(MutationToken token, ReplicateTo replicateTo, PersistTo persistTo)
{
var keyMapper = (VBucketKeyMapper)_configInfo.GetKeyMapper();
var obParams = new ObserveParams
{
ReplicateTo = replicateTo,
PersistTo = persistTo,
Token = token,
VBucket = keyMapper[token.VBucketId]
};
obParams.CheckConfiguredReplicas();
var op = new ObserveSeqno(obParams.Token, _transcoder, _timeout);
using (var cts = new CancellationTokenSource((int)_timeout))
{
//perform the observe operation at the set interval and terminate if not successful by the timeout
var task = await ObserveEvery(async p =>
{
IServer master;
var attempts = 0;
while ((master = p.VBucket.LocatePrimary()) == null)
{
if (attempts++ > 10) { throw new TimeoutException("Could not acquire a server."); }
await Task.Delay((int)Math.Pow(2, attempts)).ContinueOnAnyContext();
}
var result = master.Send(op);
var osr = result.Value;
p.CheckMutationLost(osr);
p.CheckPersisted(osr);
if (p.IsDurabilityMet())
{
return true;
}
return await CheckReplicasAsync(p, op).ContinueOnAnyContext();
}, obParams, _interval, op, cts.Token).ContinueOnAnyContext();
return task;
}
}
/// <summary>
/// Checks the replicas for durability constraints.
/// </summary>
/// <param name="observeParams">The observe parameters.</param>
/// <param name="op">The op.</param>
/// <returns></returns>
bool CheckReplicas(ObserveParams observeParams, ObserveSeqno op)
{
var replicas = observeParams.GetReplicas();
return(replicas.Any(replicaId => CheckReplica(observeParams, op, replicaId)));
}
/// <summary>
/// Checks a replica for durability constraints.
/// </summary>
/// <param name="observeParams">The observe parameters.</param>
/// <param name="op">The op.</param>
/// <param name="replicaId">The replica identifier.</param>
/// <returns></returns>
private bool CheckReplica(ObserveParams observeParams, ObserveSeqno op, int replicaId)
{
var cloned = (ObserveSeqno)op.Clone();
var replica = observeParams.VBucket.LocateReplica(replicaId);
var result = replica.Send(cloned);
observeParams.CheckMutationLost(result);
observeParams.CheckPersisted(result);
observeParams.CheckReplicated(result);
return observeParams.IsDurabilityMet();
}
async Task<bool> CheckReplicasAsync(ObserveParams observeParams, ObserveSeqno op)
{
var replicas = observeParams.GetReplicas();
var tasks = new List<Task<bool>>();
replicas.ForEach(x => tasks.Add(CheckReplicaAsync(observeParams, op, x)));
await Task.WhenAll(tasks);
return observeParams.IsDurabilityMet();
}
private async Task<bool> CheckReplicaAsync(ObserveParams observeParams, int replicaId)
{
var op = new ObserveSeqno(observeParams.Token, _clusterController.Transcoder, _timeout);
observeParams.Operation = op;
var tcs = new TaskCompletionSource<IOperationResult<ObserveSeqnoResponse>>();
op.Completed = CallbackFactory.CompletedFuncForRetry(_pending, _clusterController, tcs);
_pending.TryAdd(op.Opaque, op);
Log.Debug(m => m("checking replica {0} - opaque: {1}", replicaId, op.Opaque));
var replica = observeParams.VBucket.LocateReplica(replicaId);
await replica.SendAsync(op).ContinueOnAnyContext();
var response = await tcs.Task.ContinueOnAnyContext();
observeParams.CheckMutationLost(response);
observeParams.CheckPersisted(response);
observeParams.CheckReplicated(response);
return observeParams.IsDurabilityMet();
}
/// <summary>
/// Observes the specified key using the Seqno.
/// </summary>
/// <param name="key">The key.</param>
/// <param name="token">The token.</param>
/// <param name="replicateTo">The replicate to.</param>
/// <param name="persistTo">The persist to.</param>
/// <returns>True if durability constraints were matched.</returns>
/// <exception cref="DocumentMutationLostException">Thrown if the observed document was lost during
/// a hard failover because the document did not reach the replica in time.</exception>
/// <exception cref="ReplicaNotConfiguredException">Thrown if the number of replicas requested
/// in the ReplicateTo parameter does not match the # of replicas configured on the server.</exception>
public bool Observe(MutationToken token, ReplicateTo replicateTo, PersistTo persistTo)
{
var keyMapper = (VBucketKeyMapper)_configInfo.GetKeyMapper();
var p = new ObserveParams
{
ReplicateTo = replicateTo,
PersistTo = persistTo,
Token = token,
VBucket = keyMapper[token.VBucketId]
};
p.CheckConfiguredReplicas();
var op = new ObserveSeqno(p.Token, _transcoder, _timeout);
do
{
var master = p.VBucket.LocatePrimary();
var result = master.Send(op);
var osr = result.Value;
p.CheckMutationLost(osr);
p.CheckPersisted(osr);
if (p.IsDurabilityMet())
{
return true;
}
if (CheckReplicas(p, op))
{
return true;
}
//prepare for another attempt
op = (ObserveSeqno)op.Clone();
p.Reset();
} while (!op.TimedOut());
return false;
}
/// <summary>
/// Checks the replicas for durability constraints.
/// </summary>
/// <param name="observeParams">The observe parameters.</param>
/// <param name="op">The op.</param>
/// <returns></returns>
bool CheckReplicas(ObserveParams observeParams, ObserveSeqno op)
{
var replicas = observeParams.GetReplicas();
return replicas.Any(replicaId => CheckReplica(observeParams, op, replicaId));
}
/// <summary>
/// Observes a set of keys at a specified interval and timeout.
/// </summary>
/// <param name="observe">The func to call at the specific interval</param>
/// <param name="observeParams">The parameters to pass in.</param>
/// <param name="interval">The interval to check.</param>
/// <param name="cancellationToken">The <see cref="CancellationToken"/> to use to terminate the observation at the specified timeout.</param>
/// <returns>True if the durability requirements specified by <see cref="PersistTo"/> and <see cref="ReplicateTo"/> have been satisfied.</returns>
static async Task <bool> ObserveEvery(Func <ObserveParams, Task <bool> > observe, ObserveParams observeParams, int interval, ObserveSeqno op, CancellationToken cancellationToken)
{
while (true)
{
var result = await observe(observeParams).ContinueOnAnyContext();
if (result)
{
return(true);
}
var task = Task.Delay(interval, cancellationToken).ContinueOnAnyContext();
try
{
await task;
}
catch (TaskCanceledException)
{
return(false);
}
//prepare for a second attempt
op = (ObserveSeqno)op.Clone();
observeParams.Reset();
}
}
static Task<bool> CheckReplicaAsync(ObserveParams observeParams, ObserveSeqno op, int replicaId)
{
var cloned = (ObserveSeqno)op.Clone();
var replica = observeParams.VBucket.LocateReplica(replicaId);
var result = replica.Send(cloned);
observeParams.CheckMutationLost(result.Value);
observeParams.CheckPersisted(result.Value);
observeParams.CheckReplicated(result.Value);
return Task.FromResult(observeParams.IsDurabilityMet());
}
private async Task<bool> CheckPersistToAsync(ObserveParams observeParams)
{
if (observeParams.PersistTo == PersistTo.Zero) return true;
var op = new ObserveSeqno(observeParams.Token, _clusterController.Transcoder, _timeout);
observeParams.Operation = op;
var tcs = new TaskCompletionSource<IOperationResult<ObserveSeqnoResponse>>();
op.Completed = CallbackFactory.CompletedFuncForRetry(_pending, _clusterController, tcs);
_pending.TryAdd(op.Opaque, op);
var server = await GetServerAsync(observeParams);
await server.SendAsync(op).ContinueOnAnyContext();
var response = await tcs.Task.ContinueOnAnyContext();
observeParams.CheckMutationLost(response);
observeParams.CheckPersisted(response);
return observeParams.IsDurabilityMet();
}