Azure Functions v3

A sample Azure Functions 3.0 project with dependency injection, github action deploy routine, ready for local development.

Notes

• Ignore the version 2.0 in host.json, it is not related to the runtime version
• Timeout limit and other settings can be specified in host.json
• Create as many folders and functions as you want in the Functions folder
• New functions will appear in Function app after a deploy

How to run Azure functions locally

Azure Functions will run locally like they run in Azure, if you want to start a timer on demand you can trigger it with a script or use Postman to send requests. Azure blob storage credentials can be added to local.settings.json if you don’t like the additional step of starting Azurite manually.

• Install azure-functions-core-tools to get the Func CLI
• Install azurite to get local blob storage

# Prerequisites
npm i -g azure-functions-core-tools@3 --unsafe-perm true
npm i -g azurite
# Build the project
dotnet build
# Run the blob storage emulator
azurite-blob
# Start function host with a single active function
func start --functions HorseTimer
# While function host is running, you can trigger functions with a POST request
http://localhost:7071/admin/functions/HorseTimer

Use the Dependency Injection container

This works just like it does in ASP.NET Core applications

• Add a service to the DI-container in Startup.cs
• View an example service FakeClient.cs
• View an example function HorseTimer.cs

Deploy functions to Azure with Github Actions

• Create an Azure blob storage account in Azure Portal
• Create an App setting named AzureWebJobsStorage with blob account connection string
• Download publish settings from Azure Function App in Azure Portal
• Create a Github secret named AZURE_FUNCTIONAPP_PUBLISH_PROFILE, paste publish settings
• Insert application name in Github action workflow Azure.yml
• Deploy to Azure by pushing a commit to main branch

Related documentation

• Azurite
• Core tools
• Class library
• Local functions
• Github Actions