feat: adding Azure Log Analytics module (#639)

* loganalytics module

* chg terraform rg prefix

* move unit test

* rm azure ref

* refactor test

* loganalytics module

* chg terraform rg prefix

* move unit test

* rm azure ref

* refactor test

* rebase

* rm spaces

* add comment

* cleanup nits

* consistency

* fix cmts + func

* rm space

* unit test

* rm 0 lgth string for ws

* refactor exists

* ref unit test

* update pin version comments.

* Fix linting errors

* fix spacing.

* use tolower gfor sku assert

* add // +build azure

* resolve PR comments

* update loganalytics_test

Co-authored-by: wmattlong <[email protected]>
Co-authored-by: richard guthrie <[email protected]>
Co-authored-by: Hadwa Abdelhalem <[email protected]>

examples/azure/terraform-azure-loganalytics-example/README.md

@@ -0,0 +1,41 @@
+# Terraform Azure Log Analytics Example
+
+This folder contains a Terraform module that deploys resources in [Azure](https://azure.microsoft.com/) to demonstrate
+how you can use TerraTest to write automated tests for your Azure Terraform code. This module deploys a Log Analytics Workspace.
+
+- A [Log Analytics Workspace](https://docs.microsoft.com/azure/azure-monitor/platform/log-analytics-agent) that gives the module the following:
+  - [Name](https://docs.microsoft.com/azure/azure-monitor/learn/quick-create-workspace#:~:text=%20Create%20a%20Log%20Analytics%20workspace%20in%20the,and%20region%20as%20in%20the%20deleted...%20More%20)  with the value specified in the `loganalytics_workspace_name`  output variable.
+  - [Sku](https://docs.microsoft.com/azure/azure-monitor/learn/quick-create-workspace#:~:text=%20Create%20a%20Log%20Analytics%20workspace%20in%20the,and%20region%20as%20in%20the%20deleted...%20More%20)  with the value specified in the `loganalytics_workspace_sku`  output variable.
+  - [RetentionPeriodInDays](https://docs.microsoft.com/azure/azure-monitor/learn/quick-create-workspace#:~:text=%20Create%20a%20Log%20Analytics%20workspace%20in%20the,and%20region%20as%20in%20the%20deleted...%20More%20)  with the value specified in the `loganalytics_workspace_retention`  output variable.
+
+Check out [test/azure/terraform_azure_loganalytics_example_test.go](/test/azure/terraform_azure_loganalytics_example_test.go) to see how you can write
+automated tests for this module.
+
+Note that the Log Analytics Workspace in this module don't actually do anything; it just runs the resources for
+demonstration purposes.
+
+**WARNING**: This module and the automated tests for it deploy real resources into your Azure account which can cost you
+money. The resources are all part of the [Azure Free Account](https://azure.microsoft.com/free/), so if you haven't used that up,
+it should be free, but you are completely responsible for all Azure charges.
+
+## Running this module manually
+
+1. Sign up for [Azure](https://azure.microsoft.com/)
+1. Configure your Azure credentials using one of the [supported methods for Azure CLI
+   tools](https://docs.microsoft.com/cli/azure/azure-cli-configuration?view=azure-cli-latest)
+1. Install [Terraform](https://www.terraform.io/) and make sure it's on your `PATH`
+1. Ensure [environment variables](../README.md#review-environment-variables) are available
+1. Run `terraform init`
+1. Run `terraform apply`
+1. When you're done, run `terraform destroy`
+
+## Running automated tests against this module
+
+1. Sign up for [Azure](https://azure.microsoft.com/)
+1. Configure your Azure credentials using one of the [supported methods for Azure CLI
+   tools](https://docs.microsoft.com/cli/azure/azure-cli-configuration?view=azure-cli-latest)
+1. Install [Terraform](https://www.terraform.io/) and make sure it's on your `PATH`
+1. Configure your TerraTest [Go test environment](../README.md)
+1. `cd test/azure`
+1. `go build terraform_azure_loganalytics_example_test.go`
+1. `go test -v -run TestTerraformAzureLogAnalyticsExample`

examples/azure/terraform-azure-loganalytics-example/main.tf

@@ -0,0 +1,37 @@
+# ---------------------------------------------------------------------------------------------------------------------
+# DEPLOY LOG ANALYTICS
+# This is an example of how to deploy a Log Analytics workspace resource.
+# ---------------------------------------------------------------------------------------------------------------------
+# See test/azure/terraform_azure_loganalytics_example_test.go for how to write automated tests for this code.
+# ---------------------------------------------------------------------------------------------------------------------
+
+provider "azurerm" {
+  version = "~> 2.20"
+  features {}
+}
+
+# PIN TERRAFORM VERSION
+
+terraform {
+  # This module is now only being tested with Terraform 0.13.x. However, to make upgrading easier, we are setting
+  # 0.12.26 as the minimum version, as that version added support for required_providers with source URLs, making it
+  # forwards compatible with 0.13.x code.
+  required_version = ">= 0.12.26"
+}
+
+# ---------------------------------------------------------------------------------------------------------------------
+# DEPLOY A RESOURCE GROUP
+# ---------------------------------------------------------------------------------------------------------------------
+
+resource "azurerm_resource_group" "resource_group" {
+  name     = "terratest-log-rg-${var.postfix}"
+  location = var.location
+}
+
+resource "azurerm_log_analytics_workspace" "log_analytics_workspace" {
+  name                = "log-ws-${var.postfix}"
+  location            = azurerm_resource_group.resource_group.location
+  resource_group_name = azurerm_resource_group.resource_group.name
+  sku                 = "PerGB2018"
+  retention_in_days   = 30
+}

examples/azure/terraform-azure-loganalytics-example/outputs.tf

@@ -0,0 +1,16 @@
+output "resource_group_name" {
+  value = azurerm_resource_group.resource_group.name
+}
+
+output "loganalytics_workspace_name" {
+  value = azurerm_log_analytics_workspace.log_analytics_workspace.name
+}
+
+output "loganalytics_workspace_sku" {
+  value = azurerm_log_analytics_workspace.log_analytics_workspace.sku
+}
+
+output "loganalytics_workspace_retention" {
+  value = azurerm_log_analytics_workspace.log_analytics_workspace.retention_in_days
+}
+

examples/azure/terraform-azure-loganalytics-example/variables.tf

@@ -0,0 +1,32 @@
+# ---------------------------------------------------------------------------------------------------------------------
+# ENVIRONMENT VARIABLES
+# Define these secrets as environment variables
+# ---------------------------------------------------------------------------------------------------------------------
+
+# ARM_CLIENT_ID
+# ARM_CLIENT_SECRET
+# ARM_SUBSCRIPTION_ID
+# ARM_TENANT_ID
+
+# ---------------------------------------------------------------------------------------------------------------------
+# REQUIRED PARAMETERS
+# You must provide a value for each of these parameters.
+# ---------------------------------------------------------------------------------------------------------------------
+
+# ---------------------------------------------------------------------------------------------------------------------
+# OPTIONAL PARAMETERS
+# These parameters have reasonable defaults.
+# ---------------------------------------------------------------------------------------------------------------------
+
+
+variable "location" {
+  description = "The location to set for the storage account."
+  type        = string
+  default     = "East US"
+}
+
+variable "postfix" {
+  description = "A postfix string to centrally mitigate resource name collisions"
+  type        = string
+  default     = "resource"
+}

modules/azure/loganalytics.go

@@ -0,0 +1,72 @@
+package azure
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/Azure/azure-sdk-for-go/services/preview/operationalinsights/mgmt/2020-03-01-preview/operationalinsights"
+	"github.com/gruntwork-io/terratest/modules/testing"
+	"github.com/stretchr/testify/require"
+)
+
+// LogAnalyticsWorkspaceExists indicates whether the operatonal insights workspaces exists.
+// This function would fail the test if there is an error.
+func LogAnalyticsWorkspaceExists(t testing.TestingT, workspaceName string, resourceGroupName string, subscriptionID string) bool {
+	exists, err := LogAnalyticsWorkspaceExistsE(workspaceName, resourceGroupName, subscriptionID)
+	require.NoError(t, err)
+	return exists
+}
+
+// GetLogAnalyticsWorkspace gets an operational insights workspace if it exists in a subscription.
+// This function would fail the test if there is an error.
+func GetLogAnalyticsWorkspace(t testing.TestingT, workspaceName string, resourceGroupName string, subscriptionID string) *operationalinsights.Workspace {
+	ws, err := GetLogAnalyticsWorkspaceE(workspaceName, resourceGroupName, subscriptionID)
+	require.NoError(t, err)
+
+	return ws
+}
+
+// GetLogAnalyticsWorkspaceE gets an operational insights workspace if it exists in a subscription.
+func GetLogAnalyticsWorkspaceE(workspaceName, resoureGroupName, subscriptionID string) (*operationalinsights.Workspace, error) {
+	client, err := GetLogAnalyticsWorkspacesClientE(subscriptionID)
+	if err != nil {
+		return nil, err
+	}
+
+	ws, err := client.Get(context.Background(), resoureGroupName, workspaceName)
+	if err != nil {
+		return nil, err
+	}
+	return &ws, nil
+}
+
+// LogAnalyticsWorkspaceExistsE indicates whether the operatonal insights workspaces exists and may return an error.
+func LogAnalyticsWorkspaceExistsE(workspaceName string, resourceGroupName string, subscriptionID string) (bool, error) {
+	_, err := GetLogAnalyticsWorkspaceE(workspaceName, resourceGroupName, subscriptionID)
+	if err != nil {
+		if ResourceNotFoundErrorExists(err) {
+			return false, nil
+		}
+		return false, err
+	}
+	return true, nil
+}
+
+// GetLogAnalyticsWorkspacesClientE return workspaces client; otherwise error.
+func GetLogAnalyticsWorkspacesClientE(subscriptionID string) (*operationalinsights.WorkspacesClient, error) {
+	subscriptionID, err := getTargetAzureSubscription(subscriptionID)
+	if err != nil {
+		fmt.Println("Workspace client error getting subscription")
+		return nil, err
+	}
+
+	client := operationalinsights.NewWorkspacesClient(subscriptionID)
+	authorizer, err := NewAuthorizer()
+	if err != nil {
+		fmt.Println("authorizer error")
+		return nil, err
+	}
+
+	client.Authorizer = *authorizer
+	return &client, nil
+}

modules/azure/loganalytics_test.go

@@ -0,0 +1,30 @@
+package azure
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+/*
+The below tests are currently stubbed out, with the expectation that they will throw errors.
+If/when methods to create and delete log analytics resources are added, these tests can be extended.
+*/
+
+func TestLogAnalyticsWorkspace(t *testing.T) {
+	t.Parallel()
+
+	_, err := LogAnalyticsWorkspaceExistsE("fake", "", "")
+	assert.Error(t, err, "Workspace")
+}
+
+func TestGetLogAnalyticsWorkspaceE(t *testing.T) {
+	t.Parallel()
+	workspaceName := ""
+	resourceGroupName := ""
+	subscriptionID := ""
+
+	_, err := GetLogAnalyticsWorkspaceE(workspaceName, resourceGroupName, subscriptionID)
+	require.Error(t, err)
+}

test/azure/terraform_azure_loganalytics_example_test.go

@@ -0,0 +1,60 @@
+// +build azure
+
+// NOTE: We use build tags to differentiate azure testing because we currently do not have azure access setup for
+// CircleCI.
+
+package test
+
+import (
+	"strconv"
+	"strings"
+	"testing"
+
+	"github.com/gruntwork-io/terratest/modules/azure"
+	"github.com/gruntwork-io/terratest/modules/random"
+	"github.com/gruntwork-io/terratest/modules/terraform"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestTerraformAzureLogAnalyticsExample(t *testing.T) {
+	t.Parallel()
+
+	// subscriptionID is overridden by the environment variable "ARM_SUBSCRIPTION_ID"
+	subscriptionID := ""
+	uniquePostfix := random.UniqueId()
+
+	// website::tag::1:: Configure Terraform setting up a path to Terraform code.
+	terraformOptions := &terraform.Options{
+		// The path to where our Terraform code is located
+		TerraformDir: "../../examples/azure/terraform-azure-loganalytics-example",
+		// Variables to pass to our Terraform code using -var options
+		Vars: map[string]interface{}{
+			"postfix": uniquePostfix,
+		},
+	}
+
+	// website::tag::4:: At the end of the test, run `terraform destroy` to clean up any resources that were created
+	defer terraform.Destroy(t, terraformOptions)
+
+	// website::tag::2:: Run `terraform init` and `terraform apply`. Fail the test if there are any errors.
+	terraform.InitAndApply(t, terraformOptions)
+
+	// website::tag::3:: Run `terraform output` to get the values of output variables
+	resourceGroupName := terraform.Output(t, terraformOptions, "resource_group_name")
+	workspaceName := terraform.Output(t, terraformOptions, "loganalytics_workspace_name")
+	sku := terraform.Output(t, terraformOptions, "loganalytics_workspace_sku")
+	retentionPeriodString := terraform.Output(t, terraformOptions, "loganalytics_workspace_retention")
+
+	// website::tag::4:: Verify the Log Analytics properties and ensure it matches the output.
+	workspaceExists := azure.LogAnalyticsWorkspaceExists(t, workspaceName, resourceGroupName, subscriptionID)
+	assert.True(t, workspaceExists, "log analytics workspace not found.")
+
+	actualWorkspace := azure.GetLogAnalyticsWorkspace(t, workspaceName, resourceGroupName, subscriptionID)
+
+	actualSku := string(actualWorkspace.Sku.Name)
+	assert.Equal(t, strings.ToLower(sku), strings.ToLower(actualSku), "log analytics sku mismatch")
+
+	actualRetentionPeriod := *actualWorkspace.RetentionInDays
+	expectedPeriod, _ := strconv.ParseInt(retentionPeriodString, 10, 32)
+	assert.Equal(t, int32(expectedPeriod), actualRetentionPeriod, "log analytics retention period mismatch")
+}