/// <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()));
}
/// <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>
/// 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);
}
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());
}
/// <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>
/// 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>
/// 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();
}
