/// <summary>
/// Perform read-only operations in a consistent context.It guarantees that multiple operations on multiple collections, even on a multi-node clusters
/// give a consistent result. No write operation (normal or transactional) will be executed while the context is open.
///
/// </summary>
/// <param name="action">Should contain a list of queries performed on a <see cref="ConsistentContext"/></param>
/// <param name="collections"></param>
public void ConsistentRead(Action <ConsistentContext> action, [NotNull] params string[] collections)
{
if (collections.Length == 0)
{
throw new ArgumentException("Value cannot be an empty collection.", nameof(collections));
}
// check that the collections have been declared
lock (_collectionSchema)
{
foreach (var collection in collections)
{
if (!_collectionSchema.ContainsKey(collection))
{
throw new NotSupportedException(
$"Unknown collection {collection}. Use Connector.DeclareCollection");
}
}
}
Guid sessionId = default;
try
{
sessionId = Client.AcquireLock(false, collections);
action(new ConsistentContext(sessionId, this, collections));
}
finally
{
Client.ReleaseLock(sessionId);
}
}
public void Lock_Disposable()
{
var client = new Client();
const string keyName = "test/lock/disposable";
using (var l = client.AcquireLock(keyName))
{
Assert.IsTrue(l.IsHeld);
}
}
public void Lock_EphemeralAcquireRelease()
{
var client = new Client();
const string keyName = "test/lock/ephemerallock";
var sessionId = client.Session.Create(new SessionEntry { Behavior = SessionBehavior.Delete });
using (var l = client.AcquireLock(new LockOptions(keyName) { Session = sessionId.Response }, CancellationToken.None))
{
Assert.IsTrue(l.IsHeld);
client.Session.Destroy(sessionId.Response);
}
Assert.IsNull(client.KV.Get(keyName).Response);
}
public void Lock_EphemeralAcquireRelease()
{
var client = new Client();
const string keyName = "test/lock/ephemerallock";
var sessionId = client.Session.Create(new SessionEntry {
Behavior = SessionBehavior.Delete
});
using (var l = client.AcquireLock(new LockOptions(keyName)
{
Session = sessionId.Response
}, CancellationToken.None))
{
Assert.IsTrue(l.IsHeld);
client.Session.Destroy(sessionId.Response);
}
Assert.IsNull(client.KV.Get(keyName).Response);
}
public void Lock_Disposable()
{
var client = new Client();
const string keyName = "test/lock/disposable";
using (var l = client.AcquireLock(keyName))
{
Assert.IsTrue(l.IsHeld);
}
}