Create HttpTrigger for AzureFunction using Terraform

Question

I'm trying to deploy Azure Function infrastructure along with HttpTrigger using Terraform. I know that using Terraform I'll create the infrastructure and the triggering part is code responsibility. But still do not understand how to create HttpTrigger. Could you please advise?

terraform {
  required_providers {
    azurerm = {
      source = "hashicorp/azurerm"
      version = "~> 2.26"
    }
  }
}
###############################
# Configure the Azure provider
provider "azurerm" {
  features {}
}
###############################
# Data
data "archive_file" "file_function_app" {
  type        = "zip"
  source_dir  = "./function-app"
  output_path = "./function-app.zip"
}
###############################
# Resource Group
resource "azurerm_resource_group" "rg" {
  name     = "${var.project}-rg"
  location = var.location
}
###############################
# App service
resource "azurerm_app_service_plan" "app_service_plan" {
  name                = "${var.project}-app-service-plan"
  resource_group_name = azurerm_resource_group.rg.name
  location            = var.location
  kind                = "FunctionApp"
  reserved = true
  sku {
    tier = "Dynamic"
    size = "Y1"
  }
}
###############################
# Function
resource "azurerm_function_app" "function_app" {
  name                       = "${var.project}-function-app"
  resource_group_name        = azurerm_resource_group.rg.name
  location                   = var.location
  app_service_plan_id        = azurerm_app_service_plan.app_service_plan.id
  app_settings = {
    "WEBSITE_RUN_FROM_PACKAGE" = "https://${azurerm_storage_account.storage_account.name}.blob.core.windows.net/${azurerm_storage_container.storage_container.name}/${azurerm_storage_blob.storage_blob.name}${data.azurerm_storage_account_blob_container_sas.storage_account_blob_container_sas.sas}",
    "FUNCTIONS_WORKER_RUNTIME" = "python",
    "APPINSIGHTS_INSTRUMENTATIONKEY" = ""
  }

  os_type = "linux"
  site_config {
    linux_fx_version          = "python|3.7"
  }
  storage_account_name       = azurerm_storage_account.storage_account.name
  storage_account_access_key = azurerm_storage_account.storage_account.primary_access_key
  version                    = "~3"

}

###############################
# Storage account
resource "azurerm_storage_account" "storage_account" {
  name = "${var.project}storage"
  resource_group_name = azurerm_resource_group.rg.name
  location = var.location
  account_tier = "Standard"
  account_replication_type = "LRS"
}
resource "azurerm_storage_container" "storage_container" {
  name                  = "function-scm"
  storage_account_name  = azurerm_storage_account.storage_account.name
  container_access_type = "private"
}
resource "azurerm_storage_blob" "storage_blob" {
  name = "${filesha256(data.archive_file.file_function_app.output_path)}.zip"
  storage_account_name = azurerm_storage_account.storage_account.name
  storage_container_name = azurerm_storage_container.storage_container.name
  type = "Block"
  source = data.archive_file.file_function_app.output_path
}
data "azurerm_storage_account_blob_container_sas" "storage_account_blob_container_sas" {
  connection_string = azurerm_storage_account.storage_account.primary_connection_string
  container_name    = azurerm_storage_container.storage_container.name

  start = "2021-01-01T00:00:00Z"
  expiry = "2022-04-04T00:00:00Z"

  permissions {
    read   = true
    add    = false
    create = false
    write  = false
    delete = false
    list   = false
  }

Function-app folder with python code has two files: 1. init .py

import logging
import azure.functions as func


def main(req: func.HttpRequest) -> func.HttpResponse:
    logging.info('Python HTTP trigger function processed a request.')

    name = req.params.get('name')
    if not name:
        try:
            req_body = req.get_json()
        except ValueError:
            pass
        else:
            name = req_body.get('name')

    if name:
        return func.HttpResponse(f"Hello {name}!")
    else:
        return func.HttpResponse(
            "Please pass a name on the query string or in the request body",
            status_code=400
        )

2. function.json

   {
      "scriptFile": "__init__.py",
      "bindings": [
        {
          "authLevel": "function",
          "type": "httpTrigger",
          "direction": "in",
          "name": "req",
          "methods": [
            "get",
            "post"
          ]
        },
        {
          "type": "http",
          "direction": "out",
          "name": "$return"
        }
      ]
    }

Deployment process completed successfully through Azure pipeline. On Azure portal, when I'm trying to open AzureFunction -> Functions, I do not see anything.

But, in App Files I do see previously created python function files

Answer 1

To create a HTTP Trigger function app using terraform.

1. Create a Sample HTTP Trigger function using

• Function Project as Typescript
• Function as HTTP Trigger
• Function Name: Your Own
• Authorization level: Anonymous

2. Add the Below Terraform files

• Resource Group
• Storage Account
• Application Insights
• Service Plan

3.Here is the example code to enter in terraform modules folder for azure function resources

variable "LOCATION" {}

variable "RESOURCE_GROUP" {}

variable "STORAGE_ACC_NAME" {}

variable "STORAGE_ACC_KEY" {}

variable "STORAGE_CONNECTION_STRING" {}

resource "azurerm_application_insights" "func_application_insights" {

name = "func-application-insights"

location = var.LOCATION

resource_group_name = var.RESOURCE_GROUP

application_type = "Node.JS"

}

resource "azurerm_app_service_plan" "func_app_service_plan" {

name = "func-app-service-plan"

location = var.LOCATION

resource_group_name = var.RESOURCE_GROUP

kind = "FunctionApp"

reserved = true

sku {

tier = "Dynamic"

size = "Y1"

}

}

resource "azurerm_function_app" "func_function_app" {

name = "func-function-app"

location = var.LOCATION

resource_group_name = var.RESOURCE_GROUP

app_service_plan_id = azurerm_app_service_plan.func_app_service_plan.id

app_settings = {

FUNCTIONS_WORKER_RUNTIME = "node",

AzureWebJobsStorage = var.STORAGE_CONNECTION_STRING,

APPINSIGHTS_INSTRUMENTATIONKEY = azurerm_application_insights.func_application_insights.instrumentation_key,

WEBSITE_RUN_FROM_PACKAGE = "1"

}

os_type = "linux"

storage_account_name = var.STORAGE_ACC_NAME

storage_account_access_key = var.STORAGE_ACC_KEY

version = "~3"

lifecycle {

ignore_changes = [

app_settings["WEBSITE_RUN_FROM_PACKAGE"]

]

}

# FIXME: Use DNS names instead of enabling CORS

site_config {

cors {

allowed_origins = ["*"]

}

}

}

For complete details on creating azure functions using Terraform please check this document . and here is the complete source code