protected abstract IStreamQueryDistributor CreateDistributor(
Func<Lease, Task> onReceive = null,
LeasableResource[] leasableResources = null,
int maxDegreesOfParallelism = 5,
[CallerMemberName] string name = null,
TimeSpan? waitInterval = null,
string scope = null);
protected override IStreamQueryDistributor CreateDistributor(
Func<Lease, Task> onReceive = null,
LeasableResource[] leasableResources = null,
int maxDegreesOfParallelism = 1,
string name = null,
TimeSpan? waitInterval = null,
string scope = null)
{
leasableResources = leasableResources ?? DefaultLeasableResources;
scope = scope ?? DateTimeOffset.UtcNow.Ticks.ToString();
distributor = new SqlBrokeredStreamQueryDistributor(
leasableResources,
settings,
scope,
maxDegreesOfParallelism,
waitInterval,
DefaultLeaseDuration);
if (onReceive != null)
{
distributor.OnReceive(onReceive);
}
ProvisionLeasableResources(leasableResources, scope);
return distributor;
}
public InMemoryStreamQueryDistributor(
LeasableResource[] leasableResources,
string scope,
int maxDegreesOfParallelism = 5,
TimeSpan? waitInterval = null) :
base(leasableResources,
maxDegreesOfParallelism,
waitInterval)
{
if (scope == null)
{
throw new ArgumentNullException("scope");
}
workInProgress = workInProgressGlobal.GetOrAdd(scope, s => new ConcurrentDictionary<LeasableResource, Lease>());
}
protected StreamQueryDistributorBase(
LeasableResource[] leasableResources,
int maxDegreesOfParallelism = 5,
TimeSpan? waitInterval = null)
{
if (leasableResources == null)
{
throw new ArgumentNullException("leasableResources");
}
if (maxDegreesOfParallelism <= 0)
{
throw new ArgumentException("maxDegreesOfParallelism must be at least 1.");
}
this.leasableResources = leasableResources;
this.maxDegreesOfParallelism = Math.Min(maxDegreesOfParallelism, leasableResources.Count());
this.waitInterval = waitInterval ?? TimeSpan.FromSeconds(.5);
}
public Lease(
LeasableResource leasableResource,
TimeSpan duration,
dynamic ownerToken = null,
Func<TimeSpan, Task> extend = null)
{
if (leasableResource == null)
{
throw new ArgumentNullException("leasableResource");
}
this.leasableResource = leasableResource;
this.duration = duration;
this.ownerToken = ownerToken;
this.extend = extend;
cancellationTokenSource.CancelAfter(Duration);
}
protected override IStreamQueryDistributor CreateDistributor(
Func<Lease, Task> onReceive = null,
LeasableResource[] leasableResources = null,
int maxDegreesOfParallelism = 5,
string name = null,
TimeSpan? waitInterval = null,
string scope = null)
{
distributor = new InMemoryStreamQueryDistributor(
leasableResources ?? DefaultLeasableResources,
scope ?? DateTimeOffset.UtcNow.Ticks.ToString(),
maxDegreesOfParallelism,
waitInterval);
if (onReceive != null)
{
distributor.OnReceive(onReceive);
}
return distributor;
}
private void ProvisionLeasableResources(LeasableResource[] leasableResources, string scope)
{
using (var connection = new SqlConnection(settings.ConnectionString))
{
connection.Open();
foreach (var resource in leasableResources)
{
var cmd = connection.CreateCommand();
cmd.CommandType = CommandType.Text;
cmd.CommandText = @"
IF NOT EXISTS (SELECT * FROM [Alluvial].[Leases]
WHERE Scope = @scope AND
ResourceName = @resourceName)
BEGIN
INSERT INTO [Alluvial].[Leases]
([ResourceName],
[Scope],
[LastGranted],
[LastReleased],
[Expires])
VALUES
(@resourceName,
@scope,
@lastGranted,
@lastReleased,
@expires)
END";
cmd.Parameters.AddWithValue(@"@resourceName", resource.Name);
cmd.Parameters.AddWithValue(@"@scope", scope);
cmd.Parameters.AddWithValue(@"@lastGranted", resource.LeaseLastGranted);
cmd.Parameters.AddWithValue(@"@lastReleased", resource.LeaseLastReleased);
cmd.Parameters.AddWithValue(@"@expires", DateTimeOffset.MinValue);
cmd.ExecuteScalar();
}
}
}
