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Issues running event hub triggered azure function locally, getting "Out of retries creating lease for partition" error on startup

Currently I have set up the following simple azure azure function which I tested previously few days ago and worked normally but for some unknown reason it returns an error
The function setup is:
[FunctionName("EventUpdatedHubFunction")]
public async Task Run([EventHubTrigger(
"%EventConsumer:Name%",
ConsumerGroup = "%EventConsumer:ConsumerGroup%",
Connection = "EventConsumer:ConnectionString")]
EventData[] events)
{
// logic
}
And the error I am getting when I am running the function is:
[2022-03-04T12:25:32.671Z] The listener for function 'EventUpdatedHubFunction' was unable to start.
[2022-03-04T12:27:09.897Z] The listener for function 'EventUpdatedHubFunction' was unable to start. Microsoft.Azure.EventHubs.Processor: Out of retries creating lease for partition 0. Microsoft.WindowsAzure.Storage: The response ended prematurely, with at least 157 additional bytes expected. System.Net.Http: The response ended prematurely, with at least 157 additional bytes expected.
And this is my config file (which I have no reason to believe is incorrect since it has worked in the past):
{
"IsEncrypted": false,
"Values": {
"AzureWebJobsStorage": "UseDevelopmentStorage=true",
"AzureWebJobsDashboard": "UseDevelopmentStorage=true",
"FUNCTIONS_WORKER_RUNTIME": "dotnet",
"EventConsumer:Name": "event_consumer_name_test",
"EventConsumer:ConsumerGroup": "consumer_group_test",
"EventConsumer:ConnectionString": "Endpoint=.........",
"Database:ConnectionString": "Server=.;Database=TestDatabase;Trusted_Connection=True;"
}
}
So far I have attempted to:
delete and reinstall the Azure storage emulator on my machine,
delete and recreate the azure emulator database,
run the azure function solution on an another machine (in which case it actually worked).
So at this point I am out of ideas of what might be causing the problem.

The solution was: through the Azure Storage Explorer, under the Local & Attached find (Emulator - Default Ports)/Blob Containers/azure-webjobs-eventhub container and delete everything in it to free space.

Function host is not running

I have a Function App in azure and when I hit the URL of the function app it says "Function host is not running."
I am not sure where I have to check and what needs to be changed.
I tried restart but still no luck.

This usually means that there is some bad configuration in your function app which is causing the host to fail to start up. Things like having an invalid host.json or an invalid proxies.json file are a possible cause.
To diagnose, it's best to look at the function host logs. If you open your function app in the Azure portal and turn on log streaming, you should be able to get more information about what's going on.
If you're not able to find anything, please let us know the name of your function app either publicly or privately and we can help take a look at the logs for you.

I was getting this after adding dependency injection support - I had an error in the startup class which stopped the host from starting.

Thanks for responding. I see that time trigger function in it is getting an error thats causing host to stop.I resolved the error now Function host is working fine.

In Azure Function v2 you are required to set the runtime version in host.json

Make sure to transfer configuration from trigger's like an Event Hub or a Service Bus to settings->configuration in your Azure Function App resource.

I have had this problem all the time when I upgrade Microsoft.NET.Sdk.Functions 4.1.1 to Microsoft.NET.Sdk.Functions 4.1.2
If you are using 4.1.2 may sure you downgrade and your problem will be resolved likely.

In my case it was due to bad configurations in service bus trigger, please find below configurations after correction
[FunctionName("MyServiceBusSubscriber")]
public async Task MyServiceBusSubscriberListener([ServiceBusTrigger(topicName: "%TopicName%", subscriptionName: "%SubscriptionName%", Connection = "ServiceBusConnectionString")] string message)
{
await Process(message);
}
here is my local.settings.json
{
"IsEncrypted": false,
"Values": {
"AzureWebJobsStorage": "UseDevelopmentStorage=true",
"FUNCTIONS_WORKER_RUNTIME": "dotnet",
"ServiceBusConnectionString": "",
"TopicName": "",
"SubscriptionName": ""
}
}

Using Azure Functions with a different storage account depending on environment

I'm currently setting up a multiple publisher/single subscriber architecture, using Azure Storage Queues to buffer events and Azure Functions as the subscriber.
Publisher -> Queue -> Function
Creating the function is no problem, the part I am trying to work out is how to set up a development and a production deployment of the same function. I have created the function in Visual Studio, and the connection is a constant string literal:
public static class FooAdded
{
[FunctionName("FooAdded")]
public static void Run([QueueTrigger("tracker-readings", Connection = "https://foo.queue.core.windows.net/?sv=...")]string myQueueItem, TraceWriter log)
{
log.Info($"C# Queue trigger function processed: {myQueueItem}");
}
}
How can I provide a different value for the connection, depending on whether I deploy to the development environment or the live environment?

To set up local debug environment
You can use local.settings.json file to define the local settings. The prerequisite for using Azure storage locally is that you need to have Azure Storage Emulator running on your machine. In the local.settings.json file define the Azure Storage Account connection string as UseDevelopmentStorage=true. The file should look something like this:
{
"IsEncrypted": false,
"Values": {
"AzureWebJobsStorage": "UseDevelopmentStorage=true",
"AzureWebJobsDashboard": "UseDevelopmentStorage=true"
}
}
By default, if no value is provided for the Connection property of the QueueTrigger attribute, it will use the AzureWebJobsStorage setting:
public static class FooAdded
{
[FunctionName("FooAdded")]
public static void Run([QueueTrigger("tracker-readings")]string myQueueItem, TraceWriter log)
{
log.Info($"C# Queue trigger function processed: {myQueueItem}");
}
}
Alternatively, if you want to explicitly specify a connection string, then you can set the Connection to the name of the connection string (not the connection string itself), and add an entry for it in the Values section of the configuration file:
QueueTrigger("tracker-readings", Connection = "CustomConnection")
In the local.settings.json file:
{
"IsEncrypted": false,
"Values": {
"AzureWebJobsStorage": "UseDevelopmentStorage=true",
"AzureWebJobsDashboard": "UseDevelopmentStorage=true",
"CustomConnection": "Some custom connection string"
}
}
For more details refer to the official documentation:
Develop and run Azure functions locally
App settings reference
To set up an Azure environment:
The values in local.settings.json do not get published to Azure, and so a value for each setting needs to be defined in the Azure environment that you are deploying to. Note that the values for AzureWebJobsStorage and AzureWebJobsDashboard are set automatically based off the storage account you choose when creating the function.
The easiest way to define settings is through the Azure portal. Go to Application Settings in the Function App and define the actual value of the storage account connection string. You do not need to make any code changes to the azure function, it will automatically pick up the connection string from application settings.
Alternatively, you can use Azure Resource Manager templates, to deploy and update the environment settings programmatically.
Each function app you create in Azure has its own environment, so after providing values for the relevant settings, you can deploy your function to multiple environments in Azure (Dev/Test/Prod etc.) as well as debug your code locally without changing connection strings everytime.

Have the connection string in an environment variable(or an app setting in app services). You can then have the app setting set to to different values in different environments.

I am trying to work out is how to set up a development and a production deployment of the same function.
I am not clear why you want to create a function both as production and development.
Actually, Azure billing is based on your app service plan, so you create one more azure function may not cost more. You could create two function to distinguish them more clearly.
If you still want to use a single function, as Travis said, you could set two connection string in app settings for different environment.

This is a well known scenario and fully supported. All you need to do manage you deployment with the ARM Template and a Parameter File.
Deploy resources with Resource Manager templates and Azure PowerShell
The connection string, along with any other Sub/Resource Group dependent settings are just parameters.

You can set Connection to a config value (something like Connection=AppSettingsKey.DatabaseConnectionString) and then have different settings for different platforms (dev, staging, prod).
Depending on your tooling for build and deployment, you can inject config values for connection strings during one of these steps.
Another option would be to use a Keyvault secret that stores the connection string.

Deployed Azure Function (v2) not running

I have an Azure Function v2, which works locally. When deployed to Azure, everything seems to be in working order (bin folder containing binaries and function name folder with function.json).
However, when I check if they ran (viewing the logs), they aren't there on the monitor tab (No data available), the kudu log stream nor in the general function view:
2018-01-25T10:27:47 Welcome, you are now connected to log-streaming service.
2018-01-25T10:28:47 No new trace in the past 1 min(s).
2018-01-25T10:29:47 No new trace in the past 2 min(s).
Info:
Using a Timer triggered Azure Function v2 calling a:
Durable Function (but "normal" v2 functions do not work as well)
Using TFS to deploy the code to ARM generated resources
function.json:
{
"generatedBy": "Microsoft.NET.Sdk.Functions.Generator-1.0.6",
"configurationSource": "attributes",
"bindings": [
{
"type": "timerTrigger",
"schedule": "0 */1 * * * *",
"useMonitor": true,
"runOnStartup": false,
"name": "timerInfo"
}
],
"disabled": false,
"scriptFile": "../bin/Namespace.dll",
"entryPoint": "Namespace.RetrieveRedisMetrics.RunOrchestrator"
}
I have:
Deleted the function in the Azure portal
Renamed the function
Removed the blob storage "azure-webjobs-hosts" and durable-lease (forgot the exact name) containers for the function
The behavior seems similar to https://github.com/Azure/Azure-Functions/issues/618, but there is no resolution or comment on that bug.
I can't share the information app name privately (according to https://github.com/Azure/azure-webjobs-sdk-script/wiki/Sharing-Your-Function-App-name-privately), since... The function isn't logging!
Any other ideas/recommendations?

When trying to publish the function from Visual Studio to skip the TFS continuous delivery factor, I got the following popup:
Apparently, you need to set the FUNCTIONS_EXTENSION_VERSION to beta.
ARM template:
{
"name": "FUNCTIONS_EXTENSION_VERSION",
"value": "beta" // was ~1
}
Azure portal (Azure Function Application Settings):
It also works with Continuous Delivery. Only problem now is that AF v1 (preview currently) takes 3 to 4 times longer than the AF v1. But that is another story..

.NET class library as an Azure Function App with ServiceBusTopic trigger does not work

I created an Azure function app locally in Visual Studio 2017(Not Azure portal) by following the steps at the following URL.
https://blogs.msdn.microsoft.com/appserviceteam/2017/03/16/publishing-a-net-class-library-as-a-function-app
I followed the steps exactly to create a function that has a “ServiceBusTopicTrigger”. I added the following to my function.json
{
“disabled”: false,
“bindings”: [
{
“name”: “mySbMsg”,
“type”: “serviceBusTrigger”,
“direction”: “in”,
“topicName”: “negotiatedaddcharge_test”,
“subscriptionName”: “clientdispatches”,
“connection”: “servicebusnac”,
“accessRights”: “manage”
}
]
}
My appsenttings.json has the following
{
“IsEncrypted”: true,
“Values”: {
“servicebusnac”: “Endpoint=MyCompanyEndPointPlaceHolder”
}
}
When I run the function in Visual Studio I keep getting an error message “Microsoft.Azure.WebJobs.ServiceBus: Microsoft Azure WebJobs SDK ServiceBus connection string ‘AzureWebJobsservicebusnac’ is missing or empty.”
Just for the heck of it I added another entry to the values collection with the name “AzureWebJobsservicebusnac” but still the same message shows up. Is there something that I am doing wrong?
Also how do you unit test this function? I cannot Access any function in the csx file in my unit test project.
Thanks.
Edited:
I added information to make it clear that I am creating the function in Visual Studio rather than the Azure portal.

Function App will search for your Service Bus connection strings in Environment variables. You can set those from Azure portal:
Go to your Function App.
Select Platform features tab above the editor.
Click Application settings.
Under App settings section add an entry with connection name and string.
The appsettings.json file is used to support local development only, and settings defined there are not published to Azure.

The solution is simple; I actually ran into this myself and it had me completely stumped for a while.
In your appsettings.json, change "IsEncrypted" from true to false. This should fix the issue you're seeing.
The error messages are less than ideal for this scenario; the Azure Functions team already has a bugfix in for it.
Hope this helps anyone who runs into this issue. (I swear, it was a week before I figured this out, and not without help.)