Solving the Frustrating “Cannot find dotnet version” Error when Deploying Flex Consumption Function App with GitHub Actions

Are you tired of banging your head against the wall trying to deploy your Flex Consumption Function App with GitHub Actions, only to be greeted with the infuriating “Cannot find dotnet version” error? Fear not, dear developer, for you’re not alone! In this comprehensive guide, we’ll delve into the depths of this issue and provide you with clear, step-by-step instructions to overcome this hurdle and get your app deployed in no time.

Understanding the Problem

The “Cannot find dotnet version” error typically occurs when GitHub Actions can’t detect the .NET version required by your Function App. This might happen due to various reasons, including:

• Misconfigured `dotnet` version in your `functionapp.yml` file
• Inconsistent .NET versioning between your local development environment and the GitHub Actions environment
• Missing or incorrect `Runtime` configuration in your `host.json` file
• Issue with the GitHub Actions workflow file (`.yml`)

Step 1: Verify Your `functionapp.yml` File

The first step in resolving this issue is to review your `functionapp.yml` file, which is used to define the configuration for your Function App. Make sure the `dotnet` version specified in this file matches the version required by your app.

runtime: custom
platform:
  os: linux
  architecture: x64
extends:
  template: ./template.yaml
functions:
  - hello-world
  - second-function
stack:
  dotnet: 6.0

In the example above, we’re specifying `dotnet: 6.0` as the required .NET version. Ensure this version aligns with the one used in your local development environment and the one specified in your `host.json` file (which we’ll discuss later).

Step 2: Confirm Consistent .NET Versioning

To avoid any versioning discrepancies, ensure you’re using the same .NET version across all environments, including:

• Local development environment (e.g., Visual Studio)
• GitHub Actions environment (specified in `functionapp.yml`)
• `host.json` file

You can check the .NET version used in your local environment by running the following command in your terminal:

dotnet --version

Note down the version number and ensure it matches the one specified in your `functionapp.yml` file and `host.json` file.

Step 3: Review Your `host.json` File

The `host.json` file is used to configure the Function App host. Verify that the `Runtime` configuration is correctly set to the desired .NET version. In this example, we’re using .NET 6.0:

{
  "version": "2.0",
  "managedDependency": {
    "enabled": true
  },
  "runtime": "dotnet-isolated",
  "runtimeVersion": "6.0"
}

Make sure the `runtimeVersion` property is set to the correct .NET version, which should match the one specified in your `functionapp.yml` file and local development environment.

Step 4: Update Your GitHub Actions Workflow File

The GitHub Actions workflow file (`.yml`) is responsible for defining the deployment process. Update the file to ensure it uses the correct .NET version and runtime:

name: Deploy to Azure Functions

on:
  push:
    branches:
      - main

jobs:
  deploy:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout code
        uses: actions/checkout@v2

      - name: Login to Azure
        uses: azure/login@v1
        with:
          creds: ${{ secrets.AZURE_CREDENTIALS }}

      - name: Install .NET 6.0
        run: |
          dotnet tool install -g Azure.Functions.Cli
          dotnet --version

      - name: Deploy to Azure Functions
        uses: azure/azure-functions-action@v1
        with:
          app-name: my-function-app
          package: ./my-function-app
          runtime: dotnet-isolated
          runtime-version: 6.0

In the example above, we’re using `runtime: dotnet-isolated` and `runtime-version: 6.0` to specify the correct .NET version and runtime.

Step 5: Verify and Deploy

After updating your `functionapp.yml`, `host.json`, and GitHub Actions workflow files, commit and push the changes to your repository. Trigger the GitHub Actions deployment process to verify that the “Cannot find dotnet version” error has been resolved.

If you’re still encountering issues, review the GitHub Actions logs to identify the root cause of the problem.

Conclusion

In this article, we’ve walked you through the steps to resolve the frustrating “Cannot find dotnet version” error when deploying a Flex Consumption Function App with GitHub Actions. By verifying your `functionapp.yml` file, ensuring consistent .NET versioning, reviewing your `host.json` file, and updating your GitHub Actions workflow file, you should be able to successfully deploy your app.

Remember to stay calm and methodically troubleshoot each step to identify the root cause of the issue. With these instructions, you’ll be well on your way to deploying your Function App with confidence!

Tip	Description
Use the same .NET version across all environments	Consistency is key! Ensure the .NET version used in your local development environment, `functionapp.yml` file, and `host.json` file matches.
Verify your `functionapp.yml` file	Double-check that the `dotnet` version specified in your `functionapp.yml` file matches the required version.
Review your `host.json` file	Ensure the `Runtime` configuration is correctly set to the desired .NET version.
Update your GitHub Actions workflow file	Make sure the workflow file uses the correct .NET version and runtime.

Additional Resources

If you’re still experiencing issues or need further guidance, refer to the following resources:

• Azure Functions – .NET Isolated Process
• Azure Functions – Deployment Technologies
• GitHub Actions – Azure Functions Action

By following these steps and tips, you should be able to overcome the “Cannot find dotnet version” error and successfully deploy your Flex Consumption Function App with GitHub Actions.

Frequently Asked Question

Got stuck while deploying a Flex Consumption Function App with GitHub Actions? Worry not, friend! We’ve got you covered. Here are some FAQs to help you troubleshoot the “Cannot find dotnet version” error.