public void ProcessHostStarted_IfHostConcurrentlyUpdated_DeletesKnownFunctionsIfLatest()
{
// Arrange
const string hostId = "host";
string[] originalFunctionIds = new string[] { "a", "b" };
string[] finalFunctionIds = new string[] { "b", "d" };
IHostIndexManager concurrentlyRemoveFunctionsHostIndexManager = CreateStubHostIndexManager(
existingSnapshot: CreateHostSnapshot(DateTimeOffset.MaxValue, finalFunctionIds), persistSucceeds: true);
IFunctionIndexManager functionIndexManager = CreateFakeFunctionIndexManager();
DateTimeOffset earlierHostVersion = DateTimeOffset.MinValue;
AddFunctionToIndex(functionIndexManager, hostId, originalFunctionIds[0], earlierHostVersion);
AddFunctionToIndex(functionIndexManager, hostId, originalFunctionIds[1], earlierHostVersion);
IHostIndexer product = CreateProductUnderTest(concurrentlyRemoveFunctionsHostIndexManager,
functionIndexManager);
HostStartedMessage message = new HostStartedMessage
{
SharedQueueName = hostId,
EnqueuedOn = DateTimeOffset.Now,
Functions = new FunctionDescriptor[]
{
new FunctionDescriptor {
Id = originalFunctionIds[0]
},
new FunctionDescriptor {
Id = originalFunctionIds[1]
},
new FunctionDescriptor {
Id = "c"
},
new FunctionDescriptor {
Id = "d"
}
}
};
// Act
product.ProcessHostStarted(message);
// Assert
IEnumerable <VersionedMetadata> functions = functionIndexManager.List(hostId);
Assert.NotNull(functions); // Guard
IEnumerable <string> functionIds = functions.Select(f => f.Id).ToArray();
Assert.Equal(finalFunctionIds, functionIds);
}
public void ProcessHostStarted_UpdatesExistingFunctionsIfLatest()
{
// Arrange
const string hostId = "host";
DateTimeOffset expectedVersion = DateTimeOffset.Now;
string[] expectedFunctionIds = new string[] { "a", "b", "c" };
IHostIndexManager hostIndexManager = CreateStubHostIndexManager(
CreateHostSnapshot(expectedVersion, expectedFunctionIds), persistSucceeds: true);
IFunctionIndexManager functionIndexManager = CreateFakeFunctionIndexManager();
DateTimeOffset earlierHostVersion = DateTimeOffset.MinValue;
AddFunctionToIndex(functionIndexManager, hostId, expectedFunctionIds[0], earlierHostVersion);
AddFunctionToIndex(functionIndexManager, hostId, expectedFunctionIds[1], earlierHostVersion);
AddFunctionToIndex(functionIndexManager, hostId, expectedFunctionIds[2], earlierHostVersion);
IHostIndexer product = CreateProductUnderTest(hostIndexManager, functionIndexManager);
HostStartedMessage message = new HostStartedMessage
{
SharedQueueName = hostId,
EnqueuedOn = expectedVersion,
Functions = new FunctionDescriptor[]
{
new FunctionDescriptor {
Id = expectedFunctionIds[0]
},
new FunctionDescriptor {
Id = expectedFunctionIds[1]
},
new FunctionDescriptor {
Id = expectedFunctionIds[2]
}
}
};
// Act
product.ProcessHostStarted(message);
// Assert
IEnumerable <VersionedMetadata> functions = functionIndexManager.List(hostId);
Assert.NotNull(functions); // Guard
IEnumerable <string> functionIds = functions.Select(f => f.Id).ToArray();
Assert.Equal(expectedFunctionIds, functionIds);
IEnumerable <DateTimeOffset> versions = functions.Select(f => f.Version).ToArray();
Assert.Equal(new DateTimeOffset[] { expectedVersion, expectedVersion, expectedVersion }, versions);
}
public void ProcessHostStarted_IfHostPreviouslyRemovedButProcessingAborted_DeletesKnownFunctionsIfLatest()
{
// Arrange
const string hostId = "host";
DateTimeOffset hostVersion = DateTimeOffset.Now;
string[] previouslyProcessedFunctionIds = new string[] { "a", "b", "c" };
IHostIndexManager concurrentlyRemoveFunctionsHostIndexManager = CreateStubHostIndexManager(
existingSnapshot: null, persistSucceeds: false);
IFunctionIndexManager functionIndexManager = CreateFakeFunctionIndexManager();
AddFunctionToIndex(functionIndexManager, hostId, previouslyProcessedFunctionIds[0], hostVersion);
AddFunctionToIndex(functionIndexManager, hostId, previouslyProcessedFunctionIds[1], hostVersion);
AddFunctionToIndex(functionIndexManager, hostId, previouslyProcessedFunctionIds[2], hostVersion);
IHostIndexer product = CreateProductUnderTest(concurrentlyRemoveFunctionsHostIndexManager,
functionIndexManager);
HostStartedMessage message = new HostStartedMessage
{
SharedQueueName = hostId,
EnqueuedOn = hostVersion,
Functions = new FunctionDescriptor[]
{
new FunctionDescriptor {
Id = previouslyProcessedFunctionIds[0]
},
new FunctionDescriptor {
Id = previouslyProcessedFunctionIds[1]
},
new FunctionDescriptor {
Id = previouslyProcessedFunctionIds[2]
}
}
};
// Act
product.ProcessHostStarted(message);
// Assert
IEnumerable <VersionedMetadata> functions = functionIndexManager.List(hostId);
Assert.NotNull(functions); // Guard
IEnumerable <string> functionIds = functions.Select(f => f.Id).ToArray();
Assert.Equal(new string[0], functionIds);
}
public void ProcessHostStarted(HostStartedMessage message)
{
if (message == null)
{
throw new ArgumentNullException("message");
}
string hostId = message.SharedQueueName;
DateTimeOffset hostVersion = message.EnqueuedOn;
DateTime hostVersionUtc = hostVersion.UtcDateTime;
IEnumerable <FunctionDescriptor> messageFunctions = message.Functions ?? Enumerable.Empty <FunctionDescriptor>();
HostSnapshot newSnapshot = new HostSnapshot
{
HostVersion = hostVersion,
FunctionIds = CreateFunctionIds(messageFunctions)
};
if (_hostIndexManager.UpdateOrCreateIfLatest(hostId, newSnapshot))
{
IEnumerable <VersionedMetadata> existingFunctions = _functionIndexManager.List(hostId);
IEnumerable <VersionedMetadata> removedFunctions = existingFunctions
.Where((f) => !newSnapshot.FunctionIds.Any(i => f.Id == i));
foreach (VersionedMetadata removedFunction in removedFunctions)
{
// Remove all functions no longer in our list (unless they exist with a later host version than
// ours).
string fullId = new FunctionIdentifier(hostId, removedFunction.Id).ToString();
_functionIndexManager.DeleteIfLatest(fullId, hostVersion, removedFunction.ETag,
removedFunction.Version);
}
HeartbeatDescriptor heartbeat = message.Heartbeat;
IEnumerable <FunctionDescriptor> addedFunctions = messageFunctions
.Where((d) => !existingFunctions.Any(f => d.Id == f.Id));
foreach (FunctionDescriptor addedFunction in addedFunctions)
{
// Create any functions just appearing in our list (or update existing ones if they're earlier than
// ours).
FunctionSnapshot snapshot = CreateFunctionSnapshot(hostId, heartbeat, addedFunction, hostVersion);
_functionIndexManager.CreateOrUpdateIfLatest(snapshot);
}
// Update any functions appearing in both lists provided they're still earlier than ours (or create them
// if they've since been deleted).
var possiblyUpdatedFunctions = existingFunctions
.Join(messageFunctions, (f) => f.Id, (d) => d.Id, (f, d) => new
{
Descriptor = d,
HostVersion = f.Version,
ETag = f.ETag
});
foreach (var possiblyUpdatedFunction in possiblyUpdatedFunctions)
{
FunctionSnapshot snapshot = CreateFunctionSnapshot(hostId, heartbeat,
possiblyUpdatedFunction.Descriptor, hostVersion);
_functionIndexManager.UpdateOrCreateIfLatest(snapshot, possiblyUpdatedFunction.ETag,
possiblyUpdatedFunction.HostVersion);
}
}
// Delete any functions we may have added or updated that are no longer in the index.
// The create and update calls above may have occured after another instance started processing a later
// version of this host. If that instance had already read the existing function list before we added the
// function, it would think the function had already been deleted. In the end, we can't leave a function
// around unless it's still in the host index after we've added or updated it.
HostSnapshot finalSnapshot = _hostIndexManager.Read(hostId);
IEnumerable <FunctionDescriptor> functionsRemovedAfterThisHostVersion;
if (finalSnapshot == null)
{
functionsRemovedAfterThisHostVersion = messageFunctions;
}
else if (finalSnapshot.HostVersion.UtcDateTime > hostVersionUtc)
{
// Note that we base the list of functions to delete on what's in the HostStartedMessage, not what's in
// the addedFunctions and possibleUpdatedFunctions variables, as this instance could have been aborted
// and resumed and could lose state like those local variables.
functionsRemovedAfterThisHostVersion = messageFunctions.Where(
f => !finalSnapshot.FunctionIds.Any((i) => f.Id == i));
}
else
{
functionsRemovedAfterThisHostVersion = Enumerable.Empty <FunctionDescriptor>();
}
foreach (FunctionDescriptor functionNoLongerInSnapshot in functionsRemovedAfterThisHostVersion)
{
string fullId = new FunctionIdentifier(hostId, functionNoLongerInSnapshot.Id).ToString();
_functionIndexManager.DeleteIfLatest(fullId, hostVersionUtc);
}
_functionIndexVersionManager.UpdateOrCreateIfLatest(newSnapshot.HostVersion);
}
