Disable Azure Function from C# for runtime version 3.x? - c#

How can I disable an Azure Function using code in C#?
I'm using Azure Functions Runtime version 3.x
I'm implementing a distributed circuit-breaker inspired by Serverless circuit breakers with Durable Entities. When the circuit opens I need to disable a queue-trigged Azure Function, instead of stopping the entire function app.
I see from How to disable functions in Azure Functions that the recommended way to disable a function is to set the AzureWebJobs.<FUNCTION_NAME>.Disabled app setting. But I haven't found an API for doing that in C#. I'm hoping there is something that I can call from my C# code that is equivalent to the Azure CLI's az functionapp config appsettings set command.
I saw similar questions on SO like:
azure set environment variable programmatically to disable an azure function
and How to Enable/Disable Azure Function programmatically
But those have answers from back in 2017 that use kudu APIs to change the disabled property in the function.json file, and I'm hoping that there is a better way to do that now. Especially because the Docs at How to disable functions in Azure Functions say:
The generated function.json file for a class library function is not
meant to be edited directly. If you edit that file, whatever you do to
the disabled property will have no effect.

Unfortunately I was not able to find any documentation as such. The closest I got was
https://learn.microsoft.com/en-us/rest/api/appservice/webapps/createfunction
For instance to create the function :
https://management.azure.com/subscriptions/{subscriptionId}/resourceGroups/{resourceGroupName}/providers/Microsoft.Web/sites/{name}/functions/{functionName}?api-version=2019-08-01
However this documentation also did not take me near to your requirement of updating the Config File. Or I may have overlooked few modules. Request you check further before implementing the below steps
So here's is what I did, I was kind of trying to reverse engineer, I ran the commands in Azure CLI and captured the traces - my thought process - the Azure CLI internally run on python and issues the API request to the Azure.
Ran the below command and captured Fiddler :
az functionapp config appsettings set --name <myFunctionApp> \
--resource-group <myResourceGroup> \
--settings AzureWebJobs.QueueTrigger.Disabled=true
And Yes ! The python process was issuing request to https://management.azure.com to update appsetting :
The set property is sent in the Request Body :
We can hardcode the properties or get it dynamically.
So I ran the below Azure CLI command
az functionapp config appsettings list --name <> --resource-group <>
I was able to see the above properties that was passed along the PUT request
Took the fiddler for the above command
Saw there is a POST Request to the below endpoint :
https://management.azure.com/subscriptions//resourceGroups//providers/Microsoft.Web/sites//config/appsettings/list?api-version=2019-08-01
These are the same set of property bags which are sent as the request bodies in the PUT in order to set the property.
So in your case you will have to request the above end point to get the list of properties. It is json output. Update the value of AzureWebJobs.QueueTrigger.Disabled to True.
Issue the Updated properties using the PUT method along with the headers such as Bearer Token & Content-Type: application/json; charset=utf-8
Request URI :
https://management.azure.com/subscriptions//resourceGroups//providers/Microsoft.Web/sites//config/appsettings?api-version=2019-08-01
Headers :
Authorization: Bearer <> Content-Type: application/json;
charset=utf-8`
Request Body:
{"kind": "<class 'str'>", "properties": }
I hope you will be able to achieve your requirement.
I hope this helps you :)
I don't recommend this for your prod. Pls try and monitor in your Dev env.

Related

How to get access to kubernetes cluster from containerized application running inside node hosted on same cluster?

I am using kubernetes client library for c#. This method should ideally provide me with k8s config of the cluster it is running inside
var k8sConfig = KubernetesClientConfiguration.InClusterConfig();
Inside docker container when this run it gives
k8s.Autorest.HttpOperationException: Operation returned an invalid status code 'Forbidden'
Expected behaviour is to get cluster inside application so as to use its configmaps and secrets.
Is there any other method to do this or are there any pre-requisites to use this method?
Please note: I am using token login from web UI for cluster dashboard
If you really want to use the configmap values you can mount it to your pod as shown here.(same for secret)
https://kubernetes.io/docs/tasks/configure-pod-container/configure-pod-configmap/
Then these would be available to your pod as env variables.
https://github.com/kubernetes-client/csharp/discussions/891
I asked over github too, which was answered by moderators. And this is what we need to do here. Keep "clusterrolbinding" concept in mind.

CORS Issue with Azure Functions inside AKS Cluster

I have a AKS Cluster in Azure which is running my Azure functions project. I got it working by following this guide.
https://markheath.net/post/azure-functions-aks-keda
The service is running, however any requests from my site fail with a CORS error. If you notice on the guide the CORS option is set to * in the local.settings.json file.
I noticed that azure functions does not seem to read the local.settings.json or settings.json files when running inside a container.
I am not sure why but to get it running locally I had to set the connection strings as environment variables.
It looks like the func kubernetetes deploy --dry-run > deploy.yml does the same, as the yaml looks something like this:
data:
AzureWebJobsStorage: ConnectionStringHere
AzureSignalRConnectionString: ConnectionStringHere
AzureBlobStorage: ConnectionStringHere
FUNCTIONS_WORKER_RUNTIME: ZG90bmV0
FUNCTIONS_V2_COMPATIBILITY_MODE: dHJ1ZQ==
apiVersion: v1
kind: Secret
metadata:
name: my-app-live
namespace: default
---
apiVersion: v1
Note, there is no reference to CORS in there at all, even against the LoadBalancer.
I have done some research and it looks like others change the load balancer to nginx as a reverse proxy to deal with this. I am not sure this an option for me or what the repercussions would be as this is using DurableFunctions and KEDA for scaling and I don't want to do anything that might break that functionality.
The FunctionApp is written in C#
I am very new to Kubernetes so please give as much detail as possible if you can help.

401 Unauthorized when querying durable function status

I need some help with Azure Durable Functions.
I created a new durable function with VS Code in C# and deployed it to Azure via the VS Code azure function extension. The function app resource was already created manually in the portal. I use
FUNCTIONS_WORKER_RUNTIME: dotnet
FUNCTIONS_EXTENSION_VERSION: ~2
I can trigger the creation of an durable task and but when I query the status with the statusQueryGetUri, I only get a 401 Unauthrized. The http trigger of the function itself is anonymous and does not require authentication (for debug purpose only).
The requests look like this (I used Postman to send the requests):
HTTP POST https://{function-app}.azurewebsites.net/api/SayHello_HttpStart
Response:
{
"id": "da3259a462084e86a34f8ce9859a6ed6",
"statusQueryGetUri": "https://{function-app}.azurewebsites.net/runtime/webhooks/durabletask/instances/da3259a462084e86a34f8ce9859a6ed6?taskHub=DurableFunctionsHub&connection=Storage&code=ua4tHacVv9JDH5phKCJI1OdKGXQSB/MMUX8WIv1E0OyZANqrRY3L/g==",
"sendEventPostUri": "https://{function-app}.azurewebsites.net/runtime/webhooks/durabletask/instances/da3259a462084e86a34f8ce9859a6ed6/raiseEvent/{eventName}?taskHub=DurableFunctionsHub&connection=Storage&code=ua4tHacVv9JDH5phKCJI1OdKGXQSB/MMUX8WIv1E0OyZANqrRY3L/g==",
"terminatePostUri": "https://{function-app}.azurewebsites.net/runtime/webhooks/durabletask/instances/da3259a462084e86a34f8ce9859a6ed6/terminate?reason={text}&taskHub=DurableFunctionsHub&connection=Storage&code=ua4tHacVv9JDH5phKCJI1OdKGXQSB/MMUX8WIv1E0OyZANqrRY3L/g==",
"rewindPostUri": "https://{function-app}.azurewebsites.net/runtime/webhooks/durabletask/instances/da3259a462084e86a34f8ce9859a6ed6/rewind?reason={text}&taskHub=DurableFunctionsHub&connection=Storage&code=ua4tHacVv9JDH5phKCJI1OdKGXQSB/MMUX8WIv1E0OyZANqrRY3L/g==",
"purgeHistoryDeleteUri": "https://{function-app}.azurewebsites.net/runtime/webhooks/durabletask/instances/da3259a462084e86a34f8ce9859a6ed6?taskHub=DurableFunctionsHub&connection=Storage&code=ua4tHacVv9JDH5phKCJI1OdKGXQSB/MMUX8WIv1E0OyZANqrRY3L/g=="
}
The Get Request is then simply:
GET https://{function-app}.azurewebsites.net/runtime/webhooks/durabletask/instances/da3259a462084e86a34f8ce9859a6ed6?taskHub=DurableFunctionsHub&connection=Storage&code=ua4tHacVv9JDH5phKCJI1OdKGXQSB/MMUX8WIv1E0OyZANqrRY3L/g==
Did I miss some configuration I have to set to allow access to the uri? What logs might help me figure out what the problem is?
When I run the code locally there are no problems and everything works as expected.
Thanks a lot for all help!
Note that the statusQueryGetUri is an admin endpoint which always requires a System Key.
GET <rootUrl>/runtime/webhooks/durabletask/instances/<GUID>
?taskHub={taskHub}
&connection={connection}
&code={systemKey}
As an alternative, you could also set the x-functions-key header of the http request with this key.
More info on the usage of the HTTP endpoints in the docs.

How to make a C# REST request using a Google Cloud JSON Service account file?

I'd like to leverage the new Google TTS using a simple rest request. To that end, I've created a Service Account which downloaded a JSON file containing a private key id, a private key, client email, client id, client_x509_cert_url, etc.
I've also set the environment variable for the system:
Environment.SetEnvironmentVariable("GOOGLE_APPLICATION_CREDENTIALS", jsonFile);
I then found this sample CURL request to use the WaveNet TTS engine provided by Google:
curl -H "Authorization: Bearer "$(gcloud auth application-default print-access-token) \
-H "Content-Type: application/json; charset=utf-8" \
--data "{
'input':{
'text':'Android is a mobile operating system developed by Google,
based on the Linux kernel and designed primarily for
touchscreen mobile devices such as smartphones and tablets.'
},
'voice':{
'languageCode':'en-gb',
'name':'en-GB-Standard-A',
'ssmlGender':'FEMALE'
},
'audioConfig':{
'audioEncoding':'MP3'
}
}" "https://texttospeech.googleapis.com/v1beta1/text:synthesize" > writtenfile.txt
I want to create a simple C# webrequest from the above CURL request, but the line "gcloud auth application-default print-access-token" is a problem for me. I cannot install a CLI gcloud instance on this machine. Isn't there some way to setup the webrequest authorization access token from the JSON service account file? Surely I don't HAVE to have gcloud installed.
Looking for code sample demonstrating how to convert CURL code to a C# rest request using the service account json file without gcloud.
In case you don't want to install the gcloud packages, you can execute REST calls by using API Keys. These keys can be created directly in the GCP console and they can be passed as a parameter through the request header; in this way, you can authenticate to the service without the need of gcloud. Additionally, I suggest you to take a look on this guide that contains the steps required to make REST requests with C#.
You can use this Restlet Client tool to test the following example:
REST content Example
Header
https://texttospeech.googleapis.com/v1beta1/text:synthesize?key=<YOUR_API_KEY>
Body
{
'input':{
'text':'Android is a mobile operating system developed by Google,
based on the Linux kernel and designed primarily for
touchscreen mobile devices such as smartphones and tablets.'
},
'voice':{
'languageCode':'en-gb',
'name':'en-GB-Standard-A',
'ssmlGender':'FEMALE'
},
'audioConfig':{
'audioEncoding':'MP3'
}
}
Finally, in case you want to consume a Service Account JSON file, you can use the Client libraries to create and send your TTS requests to then authenticate them directly from your code; however, this method require to install the TextToSpeech packages.

How can I listen for the end of a build using VSTS WebApi?

I'm building as part of a larger process that analyzes the results of the build once it has completed. I used to work with XAML builds via C# code, and I had the following code:
QueuedBuild.Connect();
QueuedBuild.PollingCompleted += PrivateServerBuildRequest.BuildCompleted;
(QueuedBuild was IQueuedBuild type),
With new WebApi builds, do I have an event that let me know that the build has completed?
I found BuildCompletedEvent in Microsoft.TeamFoundation.Build.WebApi.Events but I didn't manage to find the way to use it.
Is there any equivalent to PollingCompleted event in WebApi builds? Something that'll fire once all build results are available?
One of the possible alternatives with the new REST API is to use Service Hooks. In particular, you might want to pay attention to the generic Web Hook, whcih can basically instruct VSTS to POST some JSON payload (once a certain event occurs) to some endpoint.
The endpoint can be anything: your custom home-made service hosted on-prem, OR an Azure Function, for instance. This article can give you an idea how to trigger an Azure Function in response to a VSTS event.
The 'Build Completed' event is in the list of available events.
So, to sum it all up, I would try the following in your case:
Create an Azure Function to accept the build info payload and process it accordingly
Subscribe to Build Completed event with the Web Hook and make sure the Azure Function URL is used as the endpoint

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