Azure Series Part 9: Creating your first function app via Azure portal and ARM templates

Functions are hosted in an execution context called a function app. You define function apps to logically group and structure your functions and a compute resource in Azure.

Function apps may use one of two types of service plans. The first service plan is the Consumption service plan. The plan that you choose when using the Azure serverless application platform. The Consumption service plan provides automatic scaling and bills you when your functions are running. The Consumption plan comes with a configurable timeout period for the execution of a function.

The second plan is called the Azure App Service plan. The plan allows you to avoid timeout periods by having your function run continuously on a VM that you define. When using an App Service plan, you are responsible for managing the app resources the function runs on, so this is technically not a serverless plan.

When you create a function app, it must be linked to a storage account. You can select an existing account or create a new one. The function app uses this storage account for internal operations such as logging function executions and managing execution triggers. 

Create a function via Azure Portal

Step 1: Sign into the Azure portal using the same account you activated for the sandbox.
Step 2: Select Create a resource.

Enter the following details in all tabs:

Okay, now the app is deployed. Click on the URL and check in the browser.

okay so so now the function app is up and running if the URL show above screen.

Create a function app via ARM template

Use below template.json and parameters.json files for deployment through ARM

template.json

{
    "$schema": "http://schema.management.azure.com/schemas/2015-01-01/deploymentTemplate.json#",
    "contentVersion": "1.0.0.0",
    "parameters": {
        "subscriptionId": {
            "type": "string"
        },
        "name": {
            "type": "string"
        },
        "location": {
            "type": "string"
        },
        "hostingPlanName": {
            "type": "string"
        },
        "serverFarmResourceGroup": {
            "type": "string"
        },
        "alwaysOn": {
            "type": "bool"
        },
        "storageAccountName": {
            "type": "string"
        },
        "use32BitWorkerProcess": {
            "type": "bool"
        },
        "sku": {
            "type": "string"
        },
        "skuCode": {
            "type": "string"
        },
        "workerSize": {
            "type": "string"
        },
        "workerSizeId": {
            "type": "string"
        },
        "numberOfWorkers": {
            "type": "string"
        }
    },
    "resources": [
        {
            "apiVersion": "2018-11-01",
            "name": "[parameters('name')]",
            "type": "Microsoft.Web/sites",
            "kind": "functionapp",
            "location": "[parameters('location')]",
            "tags": {
                "app": "thewebspark"
            },
            "dependsOn": [
                "[concat('Microsoft.Web/serverfarms/', parameters('hostingPlanName'))]",
                "[concat('Microsoft.Storage/storageAccounts/', parameters('storageAccountName'))]"
            ],
            "properties": {
                "name": "[parameters('name')]",
                "siteConfig": {
                    "appSettings": [
                        {
                            "name": "FUNCTIONS_EXTENSION_VERSION",
                            "value": "~3"
                        },
                        {
                            "name": "FUNCTIONS_WORKER_RUNTIME",
                            "value": "node"
                        },
                        {
                            "name": "WEBSITE_NODE_DEFAULT_VERSION",
                            "value": "~14"
                        },
                        {
                            "name": "AzureWebJobsStorage",
                            "value": "[concat('DefaultEndpointsProtocol=https;AccountName=',parameters('storageAccountName'),';AccountKey=',listKeys(resourceId('Microsoft.Storage/storageAccounts', parameters('storageAccountName')), '2019-06-01').keys[0].value,';EndpointSuffix=','core.windows.net')]"
                        },
                        {
                            "name": "WEBSITE_CONTENTAZUREFILECONNECTIONSTRING",
                            "value": "[concat('DefaultEndpointsProtocol=https;AccountName=',parameters('storageAccountName'),';AccountKey=',listKeys(resourceId('Microsoft.Storage/storageAccounts', parameters('storageAccountName')), '2019-06-01').keys[0].value,';EndpointSuffix=','core.windows.net')]"
                        },
                        {
                            "name": "WEBSITE_CONTENTSHARE",
                            "value": "[concat(toLower(parameters('name')), 'bf52')]"
                        }
                    ],
                    "use32BitWorkerProcess": "[parameters('use32BitWorkerProcess')]"
                },
                "serverFarmId": "[concat('/subscriptions/', parameters('subscriptionId'),'/resourcegroups/', parameters('serverFarmResourceGroup'), '/providers/Microsoft.Web/serverfarms/', parameters('hostingPlanName'))]",
                "clientAffinityEnabled": false
            }
        },
        {
            "apiVersion": "2018-11-01",
            "name": "[parameters('hostingPlanName')]",
            "type": "Microsoft.Web/serverfarms",
            "location": "[parameters('location')]",
            "kind": "",
            "tags": {
                "app": "thewebspark"
            },
            "dependsOn": [],
            "properties": {
                "name": "[parameters('hostingPlanName')]",
                "workerSize": "[parameters('workerSize')]",
                "workerSizeId": "[parameters('workerSizeId')]",
                "numberOfWorkers": "[parameters('numberOfWorkers')]"
            },
            "sku": {
                "Tier": "[parameters('sku')]",
                "Name": "[parameters('skuCode')]"
            }
        },
        {
            "apiVersion": "2019-06-01",
            "type": "Microsoft.Storage/storageAccounts",
            "name": "[parameters('storageAccountName')]",
            "location": "[parameters('location')]",
            "tags": {
                "app": "thewebspark"
            },
            "sku": {
                "name": "Standard_LRS"
            },
            "properties": {
                "supportsHttpsTrafficOnly": true,
                "minimumTlsVersion": "TLS1_2"
            }
        }
    ]
}

parameters.json

{
    "$schema": "https://schema.management.azure.com/schemas/2015-01-01/deploymentParameters.json#",
    "contentVersion": "1.0.0.0",
    "parameters": {
        "subscriptionId": {
            "value": "76972a65-0cc5-4520-bd43-938429557ba6"
        },
        "name": {
            "value": "thewebspark"
        },
        "location": {
            "value": "Central US"
        },
        "hostingPlanName": {
            "value": "ASP-learnf47cf806c83e4e6185d9fe3080-8bcc"
        },
        "serverFarmResourceGroup": {
            "value": "learn-f47cf806-c83e-4e61-85d9-fe3080231d21"
        },
        "alwaysOn": {
            "value": false
        },
        "storageAccountName": {
            "value": "storageaccountlearn98b3"
        },
        "sku": {
            "value": "Dynamic"
        },
        "skuCode": {
            "value": "Y1"
        },
        "workerSize": {
            "value": "0"
        },
        "workerSizeId": {
            "value": "0"
        },
        "numberOfWorkers": {
            "value": "1"
        },
        "use32BitWorkerProcess": {
            "value": true
        }
    }
}

Use the following CLI command for deployment of above template

az deployment group create --resource-group testgroup --template-file template.json --parameters parameters.json