cobalt/test-harness

Resource Deployment Testing in Cobalt

Summary of unit and integration testing for Cobalt deployed environments

Terratest is a Go library that makes it easier to write automated tests for your infrastructure as code deployments. It provides a variety of helper functions and patterns for common infrastructure testing tasks. Cobalt leverages an abstraction built ontop of Terratest called terratest-abstractions to further simplify writing unit and integration tests for Terraform deployments.

Test Setup Locally

Local Environment Setup

• You'll need to define a .env file in the root of the project. You can use our environment template file to start. cp .env.template .env
• Provide values for the environment values in .env which are required to authenticate Terraform to provision resources within your subscription.

ARM_SUBSCRIPTION_ID="<az-service-principal-subscription-id>"
ARM_CLIENT_ID="<az-service-principal-client-id>"
ARM_CLIENT_SECRET="<az-service-principal-auth-secret>"
ARM_TENANT_ID="<az-service-principal-tenant>"
ARM_ACCESS_KEY="<remote-state-storage-account-primary-key>"
TF_VAR_remote_state_account="<tf-remote-state-storage-account-name>"
TF_VAR_remote_state_container="<tf-remote-state-storage-container-name>"

Local Test Runner Options

Option 1: Docker

The benefit with running the test harness through docker is that developers don't need to worry about setting up their local environment. We strongly recommend running local-run.sh before submitting a PR as our devops pipeline runs the dockerized version of the test harness.

Prerequisites

• Docker 18.09 or later
• An Azure subscription
• A service principal
• An azure storage account for tracking terraform remote backend state. You can use our backend state setup template to provision the storage resources.
• git

Base Image Setup

Our test harness uses a base docker image to pre-package dependencies like Terraform, Go, Azure CLI, Terratest vendor packages, etc.

• Optional Step - Cobalt uses the public msftcse/cobalt-test-base base image by default. We also provide a utility script to generate a new base image.
• Rebuilding a new base image is as simple as running

./test-harness/build-base-image.sh -g "<go_version>" -t "<terraform_version>"

Script Arguments

• -g | --go_version: Golang version specification. This argument drives the version of the golang stretch base image. Defaults to 1.12.5.
• -t | --tf_version: Terraform version specification. This argument drives which terraform version release this image will use.. Defaults to 0.12.2

Keep in mind that the terraform version should align with the version from the provider module

• The base image will be tagged as:

msftcse/cobalt-test-base:g${GO_VERSION}t${TERRAFORM_VERSION}

Local Run Script

Run the test runner by calling the below script from the project's root directory. This is one of two options.

./test-harness/local-run.sh

Script Arguments

• -t | --template_name_override: The template folder to include for the test harness run(i.e. -t "azure-hello-world"). When set, the git log will be ignored. Defaults to the git log.
• -b | --docker_base_image_name: The base image to use for the test harness continer. Defaults to msftcse/cobalt-test-base:g${GO_VERSION}t${TF_VERSION}.

Option 2: Manual Setup

The benefit with setting up the test harness manually is that runtimes are quicker as we're not rebuilding the test harness image on each run.

The clear downside here is that you'll need to set up all cobalt base software packages and responsible for managing version dependency upgrades over time. Our central base image in docker hub is supported by CSE as well as version dependency upgrades.

The other downside is that you'll need to install this project within your GOPATH and pull down all dep vendor dependency packages.

Prerequisites

• An Azure subscription

• A service principal

• An azure storage account for tracking terraform remote backend state. You can use our backend state setup template to provision the storage resources.

• git

• Follow these instructions to download the Go Distribution.

• Follow these instructions to test your golang install.

• Ensure that your repository is checked out into the following directory that does not live inside $GOPATH. Example:

  $ echo $GOPATH
  /home/workspace/go
  $ pwd
  /home/workspace/oss/cobalt
  

• Install Azure CLI

• Install golang's dep package manager via Git Bash.

  curl https://raw.githubusercontent.com/golang/dep/master/install.sh | sh
  dep version
  dep:
      version     : v0.5.0
      build date  : 2018-07-26
      git hash    : 224a564
      go version  : go1.10.3
      go compiler : gc
      platform    : windows/amd64
      features    : ImportDuringSolve=false
  

• Install Terraform

Local Run Script (No-Docker Version)

Run the test runner by calling the below script from the project's root directory.

./test-harness/local-run-wo-docker.sh

Script Arguments (No-Docker Version)

• -t | --template_name_override: The template folder to include for the test harness run(i.e. -t "azure-hello-world"). When set, the git log will be ignored. Defaults to the git log.
• -c | --tf_state_container: The storage container name responsible for tracking remote state for terraform deployments. Defaults to cobaltfstate-remote-state-container
• -a | --tf_state_storage_acct: The storage account name responsible for tracking remote state for terraform deployments. Defaults to cobaltfstate.