public async Task Acquire_lock_multiple_times_work()
{
const string lockName = "my-lock";
var locker = new SqlServerDistributedAppLockProvider(_connectionFactory,
new SqlServerDistributedAppLockConfig
{
DisposeDbConnection = false
});
using (await locker.AcquireAsync(lockName))
{
// mutual exclusion scope here
}
using (await locker.AcquireAsync(lockName))
{
// mutual exclusion scope here
}
using (await locker.AcquireAsync(lockName))
{
// mutual exclusion scope here
}
}
public void Test_that_is_acquired_is_false_when_disposed()
{
var provider = new SqlServerDistributedAppLockProvider(_connectionFactory);
var theLock = provider.Acquire("this-is-my-lock");
theLock.Dispose();
Assert.False(theLock.IsActive);
}
public async Task Throws_if_given_connection_is_not_open()
{
var locker = new SqlServerDistributedAppLockProvider(() => new SqlConnection(_connectionString));
var ex = await Assert.ThrowsAsync <DistributedAppLockException>(async() => { await locker.AcquireAsync("TheLock"); });
var arEx = Assert.IsAssignableFrom <ArgumentException>(ex.InnerException);
Assert.Equal("dbConnection", arEx.ParamName);
}
public void Acquire_sync_also_works()
{
const string lockName = "my-lock";
var locker = new SqlServerDistributedAppLockProvider(_connectionFactory);
using (locker.Acquire(lockName))
{
// mutual exclusion scope here
}
}
public async Task Acquire_with_auto_expiry_throws()
{
var ex = await Assert.ThrowsAsync <DistributedAppLockException>(async() =>
{
var locker = new SqlServerDistributedAppLockProvider(_connectionFactory);
await locker.AcquireAsync("theLock", TimeSpan.Zero, TimeSpan.MaxValue);
});
Assert.IsAssignableFrom <NotSupportedException>(ex.InnerException);
}
public void Test_acquire_lock_with_timeout_works()
{
/*
* This test flow goes something like:
* 1. acquire firstLock
* 2. Start a new thread that immediately returns and waits for a while
* 3. Try to acquire second lock, but be patient and wait for up to 20 secs while retrying
* 4. thread unlocks first lock after 700 ms
* 5. thread waits 500 ms
* 6. now we expect the second call to acquire to have succeeded, assert that this is true
*/
SqlServerDistributedAppLock firstLock = null;
SqlServerDistributedAppLock secondLock = null;
var lockName = "some-other-lock";
var locker = new SqlServerDistributedAppLockProvider(_connectionFactory);
firstLock = (SqlServerDistributedAppLock)locker.Acquire(lockName, TimeSpan.FromSeconds(1));
Assert.True(firstLock.WasAcquiredInstantly);
var threadStarted = false;
// Create task to dispose of lock at some point
Task.Factory.StartNew(() =>
{
threadStarted = true;
// Wait 700 ms to allow the main thread to start acquiring second lock
var timeStart = DateTime.UtcNow;
while (DateTime.UtcNow.Subtract(timeStart).TotalMilliseconds < 700)
{
// Do nothing
}
// release the first lock
firstLock.Dispose();
// wait and the new lock should be acquired
Task.Delay(TimeSpan.FromMilliseconds(500));
Assert.Equal(lockName, secondLock.Name);
Assert.True(secondLock.IsActive);
Assert.False(secondLock.WasAcquiredInstantly);
Assert.True(secondLock.TimeUsedToAcquire.Ticks > 0);
secondLock.Dispose();
});
// Thread creation can take some time
// This waits for the thread to be created
SpinWait.SpinUntil(() => threadStarted);
// this second lock now enters retry mode
secondLock = (SqlServerDistributedAppLock)locker.Acquire(lockName, TimeSpan.FromSeconds(20));
}
public async Task Default_behavior_disposes_connection()
{
var hasBeenDisposed = false;
_connection.Disposed += (sender, args) => { hasBeenDisposed = true; };
var provider = new SqlServerDistributedAppLockProvider(_connectionFactory);
var handle = await provider.AcquireAsync("some-lock");
handle.Dispose();
await Task.Delay(50);
Assert.True(hasBeenDisposed);
Assert.Equal(ConnectionState.Closed, _connection.State);
}
public async Task Configured_behavior_leaves_connection_intact()
{
var hasBeenDisposed = false;
_connection.Disposed += (sender, args) => { hasBeenDisposed = true; };
var provider = new SqlServerDistributedAppLockProvider(_connectionFactory,
new SqlServerDistributedAppLockConfig
{
DisposeDbConnection = false
});
var handle = await provider.AcquireAsync("some-lock");
handle.Dispose();
await Task.Delay(50);
Assert.False(hasBeenDisposed);
Assert.Equal(ConnectionState.Open, _connection.State);
}
public void Cannot_acquire_lock_twice()
{
const string lockName = "second-lock";
var locker = new SqlServerDistributedAppLockProvider(_connectionFactory);
using (locker.Acquire(lockName, TimeSpan.FromSeconds(1)))
{
var ex = Assert.Throws <DistributedAppLockException>(() =>
{
// we have to create a new connection here as taking the lock twice via the same connection is OK
var otherLocker = new SqlServerDistributedAppLockProvider(() =>
{
var conn = new SqlConnection(_connectionString);
conn.Open();
return(conn);
});
return(otherLocker.Acquire(lockName));
});
Assert.Equal(DistributedAppLockExceptionReason.LockAlreadyAcquired, ex.Reason);
}
}