public async Task RestartOrchestrationWithExternalEvents()
{
using TestOrchestrationHost host = TestHelpers.GetTestOrchestrationHost(enableExtendedSessions: false);
await host.StartAsync();
// This is the local method we'll use to continuously recreate the same instance.
// It doesn't matter that the orchestration name is different as long as the instance ID is the same.
Task <TestInstance <string> > CreateInstance(int i) => host.StartInlineOrchestration(
input: "Hello, world!",
instanceId: "Singleton",
orchestrationName: $"EchoOrchestration{i}",
implementation: (ctx, input) => Task.FromResult(input));
// Start the first iteration and wait for it to complete.
TestInstance <string> instance = await CreateInstance(0);
await instance.WaitForCompletion();
int restartIterations = 10;
int externalEventCount = 10;
// We'll keep track of the execution IDs to make 100% sure we get new instances every iteration.
var executionIds = new HashSet <string> {
instance.ExecutionId
};
// Simultaneously send a bunch of external events as well as a "recreate" message. Repeat this
// several times. Need to ensure that the orchestration can always be restarted reliably. It
// doesn't matter whether the orchestration handles the external events or not.
for (int i = 1; i <= restartIterations; i++)
{
List <Task> concurrentTasks = Enumerable.Range(0, externalEventCount).Select(j => instance.RaiseEventAsync("DummyEvent", j)).ToList();
Task <TestInstance <string> > recreateInstanceTask = CreateInstance(i);
concurrentTasks.Add(recreateInstanceTask);
await Task.WhenAll(concurrentTasks);
// Wait for the newly created instance to complete.
instance = await recreateInstanceTask;
await instance.WaitForCompletion();
// Ensure that this is a new execution ID.
Assert.IsTrue(executionIds.Add(instance.ExecutionId));
}
}