Deno Worker for Azure Functions

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Overview

This is a worker that lets you run Deno on Azure Functions. It implements the Azure Functions Custom Handlers protocol and runs on the Azure Functions Consumption (serverless) plan.

The project includes a CLI denofunc to make it easy to create, run, and deploy your Deno Azure Functions apps.

Prerequisites

Note: Currently, this has only been tested to run locally on macOS. It should run on Linux and Windows as well, but needs to be verified.

Deno - 1.0.0-rc2 or above
Azure Functions Core Tools V3 - needed for running the app locally and deploying it
Azure CLI - needed to deploy the app
denofunc CLI - see below

Install the denofunc CLI

To help create, run, and deploy a Deno for Azure Functions app, you need to install the denofunc CLI. denofunc wraps the Azure Functions Core Tools (func) and is used for generating artifacts required to run/deploy the app.

To install the CLI, run the following Deno command.

deno install --allow-run --allow-read --allow-write --allow-net --unstable --name=denofunc \
    https://raw.githubusercontent.com/anthonychu/azure-functions-deno-worker/master/denofunc.ts

Getting started

Create and run an app locally

Create and change into an empty folder.
Initialize the project:
```
denofunc init
```
A few of the files that are important to know about:
- functions/hello_world.ts - a basic HTTP triggered function
- worker.ts - the Deno worker used by Azure Functions
- host.json - configuration of the function host
Run the app locally:
```
denofunc start
```
The Azure Functions Core Tools (func) is then called to run the function app.

Note: A folder is automatically generated for the hello_world function containing a file named function.json that is used by the Azure Functions runtime to load the function (they are ignored in .gitnore).
Open the URL displayed on the screen (http://localhost:7071/api/hello_world) to run the function.
Ctrl-C to stop the app.

Deploy the app to Azure

Now that you’ve run the function app locally, it’s time to deploy it to Azure!

Configure some variables (examples are in bash):

region=centralus # any region where Linux Azure Functions are available
resourceGroupName=<resource_group_name>
functionAppName=<function_app_name>
storageName=<storage_name> # must be between 3 and 24 characters in length and may contain numbers and lowercase letters only.

Run these Azure CLI commands to create and configure the function app:

# Create resource group
az group create -l $region -n $resourceGroupName

# Create storage account needed by function app
az storage account create -n $storageName -l $region -g $resourceGroupName --sku Standard_LRS

# Create function app
az functionapp create -n $functionAppName --storage-account $storageName \
    --consumption-plan-location $region -g $resourceGroupName \
    --functions-version 3 --runtime dotnet --os-type Linux

# Set app settings:
# - WEBSITE_MOUNT_ENABLED=1 enables squashfs which correctly sets the execute bit on the deno binary
az functionapp config appsettings set -n $functionAppName -g $resourceGroupName --settings "WEBSITE_MOUNT_ENABLED=1"

Deploy the app:
```
denofunc publish $functionAppName
```
Prior to deployment, denofunc tool will download the Deno Linux binary matching your locally installed version of deno that is included with the deployment package.
The deployment output will print out the URL of the deployed function. Open to the URL to run your function.

🎉 Congratulations! You’ve deployed your first Azure Functions app in Deno! 🦕

Disclaimer: This is a community open source project. No official support is provided by Microsoft.