Recently, while working on Service Bus triggered Azure Durable Function, we got an error saying “The function runtime is unable to start. Microsoft.Azure.WebJobs.ServiceBus: Microsoft Azure WebJobs SDK ServiceBus connection string ‘AzureWebJobsServiceBus’ is missing or empty”.
Below is the code that we were using:
[FunctionName("UpdateGlobalRatesOnRSLs")]
public static async Task Run([ServiceBusTrigger("%QueueName%")] Message message, MessageReceiver messageReceiver, string lockToken, [OrchestrationClient]DurableOrchestrationClient starter, ILogger log)
{
string inputMessage = Encoding.UTF8.GetString(message.Body);
log.LogInformation($"message - " + inputMessage);
MessageReceiver receiver = messageReceiver;
string token = lockToken;
}
NOTE: QueueName used above is defined in localsettings.json as a key/value pair to make it configurable.
We can fix this issue in couple of ways:
- We can provide a Connection String name in the Service Bus Trigger attribute which will be defined in localsettings.json as shown below:
[FunctionName("UpdateGlobalRatesOnRSLs")]
public static async Task Run([ServiceBusTrigger("%QueueName%", Connection = "ServiceBusConnectionString")] Message message, MessageReceiver messageReceiver, string lockToken, [OrchestrationClient]DurableOrchestrationClient starter, ILogger log)
{
string inputMessage = Encoding.UTF8.GetString(message.Body);
log.LogInformation($"message - " + inputMessage);
MessageReceiver receiver = messageReceiver;
string token = lockToken;
}
In localsettings.json:
{
"IsEncrypted": false,
"Values": {
"QueueName": "devglobalrateupdatequeue",
"ServiceBusConnectionString": "[PrimaryConnectionStringOfSharedAccessPolicy]"
}
}
- It can be left blank in the Service Bus Trigger attribute and in localsettings.json file define a key/value pair with name AzureWebJobsServiceBus
[FunctionName("UpdateGlobalRatesOnRSLs")]
public static async Task Run([ServiceBusTrigger("%QueueName%")] Message message, MessageReceiver messageReceiver, string lockToken, [OrchestrationClient]DurableOrchestrationClient starter, ILogger log)
{
string inputMessage = Encoding.UTF8.GetString(message.Body);
log.LogInformation($"message - " + inputMessage);
MessageReceiver receiver = messageReceiver;
string token = lockToken;
}
In localsettings.json:
{
"IsEncrypted": false,
"Values": {
"QueueName": "devglobalrateupdatequeue",
"AzureWebJobsServiceBus": "[PrimaryConnectionStringOfSharedAccessPolicy]"
}
}
NOTE: During deployment of the Durable Function to Azure, create the above key/value pair application settings in Function App –> Function App Settings –> Manage Application Settings –> New Application Setting and Save them.
Hope it helps !!
Ajit Patra 