Unable to get Function Host running, with the following error: Functions runtime errorMicrosoft.Azure.WebJobs.Script: Did not find functions with language [dotnet].

Question

Hello,

I am attempting to follow this guide: https://learn.microsoft.com/en-us/azure/azure-functions/functions-create-function-linux-custom-image?tabs=bash%2Cportal&pivots=programming-language-python , up until the section of 'Verify your functions on Azure' as I am unable to do so. The only deviation I believe I have made is using a B1 plan as opposed to EP1.

So far, I have pushed my image to docker, and linked it to an azure function app. The docker image runs fine locally (Windows 10). However, when I visit the azure function app I see the following error appears in the app overview, as a notification:

Functions runtime errorMicrosoft.Azure.WebJobs.Script: Did not find functions with language [dotnet].

Visiting the HTTP trigger / azure site shows that the function host is not running (I assume because of this error). As I am following a guide I am unsure of what to do next, and was advised to open a ticket by the person I spoke with in the support chat.

Cheers,
Nick

Answer 1

If using dotnet 5.0 make sure FUNCTIONS_WORKER_RUNTIME configuration value is "dotnet-isolated"

Answer 2

@Nick Wilson , Thank you for reaching out, I am sorry for the delay in my response.
I was able to replicate error on my end.

Below is the solution which worked for me.

1. On Azure Portal go to your <YourFunctionApp> scroll down on the left panel to go to “Configuration” under "Application settings" and click on “Advanced edit”.
   
2. Change the “FUNCTIONS_WORKER_RUNTIME” setting to “python” as shown below.
   
3. Click “Ok” then validate and “Save”. This will restart your function app (if not then manually restart it from the overview tab).
   
4. It will take a couple of minutes for the function to restart. On the “Overview” tab, click “Refresh” a couple of times and the error pop-up will vanish.

This also can be done using the “Azure CLI” by running the command mentioned below.

az functionapp config appsettings set --name <function_app> --resource-group <my_resource_group> --settings FUNCTIONS_WORKER_RUNTIME=python

Even though we are setting the “worker_runtime” to “python”, it is not getting reflected when deployed to the portal. This can be achieved by adding “--runtime python” to the below command in the tutorial.

az functionapp create --name <app_name> --storage-account <storage_name> --resource-group AzureFunctionsContainers-rg --plan myPremiumPlan --deployment-container-image-name <docker_id>/azurefunctionsimage:v1.0.0 --runtime python

I will contact the product team and get this rectified. I hope this resolves the issue you are facing, let me know if it does not, I will be happy to help.

Answer 3

I am getting the same error but with 'python'
Microsoft.Azure.WebJobs.Script: Did not find functions with language [python].
Value cannot be null.
Parameter name: provider

I have set the function_runtime_worked_ as python, still it is giving the same error. Can anyone please help ?

Answer 4

based on https://learn.microsoft.com/en-us/azure/azure-functions/functions-run-local?tabs=v3%2Cwindows%2Ccsharp%2Cportal%2Cbash%2Ckeda

try to install the package azure-functions-core-tools v3, like command bellow

npm install -g azure-functions-core-tools@3 --unsafe-perm true