Run Logic App Anywhere

Logic App Standard tier or Single Tenant Logic App has now provided the opportunity to build and containerise logic app and thus allowing it to run anywhere - any Cloud, On-Prem or any Infrastructure. This is hosted as an extension on the Azure Functions runtime and like Azure Function, needs a Storage account to store its state.

This also means that this containerised version of Logic App can now be hosted on managed K8s services like AKS as well as Serverless Container offerings like Azure Container Apps or on-Prem Bare metal.

Developers can now Design, Develop, Build and Run Logic App end-to-end locally; finally when everything is running fine - then deploy anywhere as they want!

The Only thing that should be considered here is the state of the Logic App which needs to be a Storage account on Azure - apart from this everything else is completely agnostic of the hosting environment!

Disclaimer:

At the time of writing this article, running anywhere randomly is not supported.

Currently supported hosting options are -

• Logic App Standard Plans
• App Service Environment V3
• Azure Arc-enabled K8s clusters

Plan

• Create a Container App hosted in a Secured Environment

• Build a Logic App with Standard tier Locally using VS Code

• Containerise the Logic App and Push the image to an private Container Registry

• Deploy the Logic App Container on Azure Container App (for simplicity)

• Test the entire flow end-to-end

• Source Code - Logic Storage App - Used in this article

• Source Code - Logic Container App - for reference

How to Setup

Set CLI Varibales

tenantId="<tenantId>"
subscriptionId="<subscriptionId>"
resourceGroup="<resourceGroup>"
monitoringResourceGroup="<monitoringResourceGroup>?"
location="<location>"
logWorkspace="<logWorkspace>"
basicEnvironment="basic-env"
securedEnvironment="secure-env"
acrName="<acrName>"
registryServer="<container_registry_server>"
registryUserName="<container_registry_username>"
registryPassword="<container_registry_password>"
​
# Optional - NOT a requirement for Contyainer Apps but mostly for microservice applications
storageName="<storage_account_name>"
​
# Optional - Primary for Securing Container Apps
containerAppVnetName="containerapp-workshop-vnet"
containerAppVnetId=
​
# Optional - Subnet for Control plane of the Container Apps Infrastructure
controlPlaneSubnetName="containerapp-cp-subnet"
controlPlaneSubnetId=
​
# Optional - Subnet for hosting Container Apps
appsSubnetName="containerapp-app-subnet"
appsSubnetId=
​
# Both Control plane Subnet and Application Services Subnet should be in same VNET viz. $containerAppVnetName

Configure Azure CLI

# Add CLI extension for Container Apps
az extension add \
  --source https://workerappscliextension.blob.core.windows.net/azure-cli-extension/containerapp-0.2.0-py2.py3-none-any.whl
  
# Register the Microsoft.Web namespace
az provider register --namespace Microsoft.Web
az provider show --namespace Microsoft.Web

Create Resource Groups

# Hosting Container Apps
az group create --name $resourceGroup --location $location
​
# Hosting Log Analytics Workspace for Container Apps
az group create --name $monitoringResourceGroup --location $location

Create Log Analytics Workspace

az monitor log-analytics workspace create --resource-group $monitoringResourceGroup --workspace-name $logWorkspace
​
# Retrieve Log Analytics ResourceId
logWorkspaceId=$(az monitor log-analytics workspace show --query customerId -g $monitoringResourceGroup -n $logWorkspace -o tsv)
​
# Retrieve Log Analytics Secrets
logWorkspaceSecret=$(az monitor log-analytics workspace get-shared-keys --query primarySharedKey -g $monitoringResourceGroup -n $logWorkspace -o tsv)

Create Container App Environment

# Simple environment with no additional security for the underlying sInfrastructure
az containerapp env create --name $basicEnvironment --resource-group $resourceGroup \
  --logs-workspace-id $logWorkspaceId --logs-workspace-key $logWorkspaceSecret --location $location

Deploy Azure Logic App as Container App

Build a Logic App with basic request/response workflow - viz. LogicContainerApp

• Run and test this Logic app as docker container locally

• Deploy the Logic App container onto Azure as a Container App

• Host the Logic App inside a Virtual Network (Secured Environment)

• Expose the container app with No Ingress - as no inblound access would be needed for this logic app

Logic App in a Container

• Let us first Create and Deploy a Logic app as Docker Container

Logic App runs an Azure Function locally and hence few tools/extensions need to be installed

Pre-Requisites

• Azure Function Core Tools - v3.x

  • The abobve link is for macOS; please install the appropriate links in the same page for other Operating Systems

  • At the time of writing, Core tools 3.x only supports the Logic App Designer within Visual Studio Code

  • The current example has been tested with - Function Core Tools version 3.0.3904 on a Windows box

• Docker Desktop for Windows

• A Storage Account on Azure - which is needed by any Azure function App

  • Logic App (aka Azure Function) would use this storage to cache its state

• VS Code Extension for Standard Logic App

• VS Code Extension for Azure Function

• VS Code extension for Docker

  • This is Optional but recommended; it makes life easy while dealing with Dockerfile and Docker CLI commands

• Create a Local folder to host all files related Logic App - viz. LogicStorageApp

• Open the folder in VS Code

• Create a New Logic App Project in this Folder

  • Choose Stateful workflow in the process and name accordingly - viz. processstgflow

  • This generates all necessary files and sub-folders within the current folder

  • A folder named processstgflow is also added which contains the workflow.json file

  • This describes the Logic App Actions/triggers

  • This example uses one Blob trigger and one Queue trigger

• Right click on the workflow.json file and Open the Logic App Designer - this might take few seconds to launch

• Add Blob trigger

• Add Queue trigger

• Save the Designer changes

• Right click on the empty area on the workspace folder structure and Open the Context menu

• Select the menu options that says - Convert to Nuget-based Logic App project

• This would generate .NET specific files - along with a LogicStorageApp.csproj file

Open the local.settings.json file

• Replace the value of AzureWebJobsStorage variable with the value from Storage Account Connection string created earlier

• Add a Dockerfile in the workspace

   

  FROM mcr.microsoft.com/azure-functions/node:3.0
  ​
  ENV AzureWebJobsScriptRoot=/home/site/wwwroot \
       AzureFunctionsJobHost__Logging__Console__IsEnabled=true \
       FUNCTIONS_V2_COMPATIBILITY_MODE=true \     
       AzureWebJobsStorage='' \
       AZURE_FUNCTIONS_ENVIRONMENT=Development \
       WEBSITE_HOSTNAME=localhost \
       WEBSITE_SITE_NAME=logicstorageapp
  ​
  COPY ./bin/Debug/netcoreapp3.1 /home/site/wwwroot

   

• WEBSITE_SITE_NAME - this is the name by which entries are created in Storage Account by the Logic App while caching its state

   

• Build docker image

docker build -t <repo_name>/<image_name>:<tag> .

docker run --name logicstorageapp -e AzureWebJobsStorage=$azureWebJobsStorage -d -p 8080:80 <repo_name>/<image_name>:<tag>