To configure a custom trigger function, remove the native NServiceBusTriggerFunction attribute. A custom trigger function can then be added manually to the project:
class CustomTriggerDefinition(IFunctionEndpoint functionEndpoint)
{
[FunctionName("MyCustomTrigger")]
public Task Run(
[ServiceBusTrigger("MyFunctionsEndpoint")]
ServiceBusReceivedMessage message,
ServiceBusClient client,
ServiceBusMessageActions messageActions,
ILogger logger,
ExecutionContext executionContext)
{
return functionEndpoint.ProcessAtomic(message, executionContext, client, messageActions, logger);
}
}
Configuring transaction mode
To use the TransportTransactionMode. mode, AutoCompleteMessages needs to be disabled and the custom trigger needs to call ProcessAtomic.
[FunctionName("ProcessMessageTx")]
public Task RunTx(
// Setting AutoComplete to false processes the message transactionally
[ServiceBusTrigger("ProcessMessageTx", AutoCompleteMessages = false)]
ServiceBusReceivedMessage message,
ServiceBusClient client,
ServiceBusMessageActions messageActions,
ILogger logger,
ExecutionContext executionContext)
{
return endpoint.ProcessAtomic(message, executionContext, client, messageActions, logger);
}
To use the TransportTransactionMode. mode, AutoCompleteMessages needs to be enabled and the trigger needs to call ProcessNonAtomic.
[FunctionName("ProcessMessage")]
public async Task Run(
// Setting AutoComplete to true (the default) processes the message non-transactionally
[ServiceBusTrigger("ProcessMessage", AutoCompleteMessages = true)]
ServiceBusReceivedMessage message,
ILogger logger,
ExecutionContext executionContext)
{
await endpoint.ProcessNonAtomic(message, executionContext, logger);
}
Incorrectly configuring the service bus trigger AutoCompleteMessages setting can lead to message loss. Use the auto-detection mechanism on the function endpoint interface, or use the trigger function attribute to specify message consistency.