Automated Infrastructure Testing

Automated infrastructure testing is a critical aspect of modern DevOps practices. It ensures that the infrastructure on which applications run is reliable, secure, and performs as expected. Automated testing can identify potential issues early in the development lifecycle, saving time and reducing the risk of deployment failures.

• Importance of Automated Infrastructure Testing
• Types of Automated Infrastructure Testing
• Best Practices for Automated Infrastructure Testing
• Chosen Automated Infrastructure Testing
• Implementation Details
  • 1. Build localstack with Docker Compose
  • 2. Create and Deploy AWS Infrastructure with Terraform
  • 3. Testing Terraform with Golang
• Conclusion

Importance of Automated Infrastructure Testing

Automated infrastructure testing provides several key benefits:

1. Consistency: Automated tests ensure that infrastructure changes are consistently applied across environments.
2. Speed: Tests can be run quickly and frequently, allowing for rapid feedback on changes.
3. Reliability: Automated tests reduce the risk of human error and improve the reliability of infrastructure deployments.
4. Security: Tests can identify vulnerabilities and configuration issues that could be exploited by attackers.
5. Scalability: Automated tests can be easily scaled to cover large and complex infrastructure setups.

Types of Automated Infrastructure Testing

Configuration Testing

Configuration testing ensures that infrastructure components are configured correctly. Tools like Inspec and Serverspec can be used to verify configurations against desired state specifications.

# Example using Inspec to check if a service is running
describe service('nginx') do
  it { should be_running }
  it { should be_enabled }
end

Best Practices for Automated Infrastructure Testing

• Shift Left: Integrate infrastructure testing early in the development process to catch issues sooner.

• Automate Everything: Automate as many tests as possible to reduce manual effort and increase test coverage.

• Use Version Control: Store infrastructure code and tests in version control systems like Git to track changes and collaborate effectively.

• Continuous Integration: Integrate automated tests into the CI/CD pipeline to ensure that tests are run on every change.

• Test in Production-like Environments: Run tests in environments that closely resemble production to identify issues that may not surface in development.

Chosen Automated Infrastructure Testing

• Terraform: Infrastructure as Code tool that allows you to define and provision infrastructure using a declarative configuration language.

• Kubernetes: Container orchestration platform that automates the deployment, scaling, and management of containerized applications.
• Docker: Platform for developing, shipping, and running applications in containers.
• Jenkins: Open-source automation server that supports building, deploying, and automating any project.

Implementation Details

1. Build localstack with Docker Compose

version: '3.8'

services:
  localstack:
    image: localstack/localstack
    ports:
      - "4566:4566"
      - "4571:4571"
    environment:
      - SERVICES=s3,lambda,dynamodb
      - DEBUG=1
    volumes:
      - "./localstack:/var/lib/localstack"

2. Create and Deploy AWS Infrastructure with Terraform

provider "aws" {
  region                      = "us-east-1"
  access_key                  = "test"
  secret_key                  = "test"
  skip_credentials_validation = true
  skip_metadata_api_check     = true
  s3_force_path_style         = true
  endpoints {
    s3 = "http://localhost:4566"
  }
}

resource "aws_s3_bucket" "example" {
  bucket = "example-bucket"
}

3. Testing Terraform with Golang

package main

import (
	"context"
	"log"
	"os"
	"testing"

	"github.com/gruntwork-io/terratest/modules/terraform"
	"github.com/stretchr/testify/assert"
	"github.com/aws/aws-sdk-go/aws"
	"github.com/aws/aws-sdk-go/aws/session"
	"github.com/aws/aws-sdk-go/service/s3"
)

func TestTerraformAwsS3(t *testing.T) {
	// Setup terraform options
	terraformOptions := &terraform.Options{
		TerraformDir: "./",
		Vars: map[string]interface{}{
			"bucket_name": "example-bucket",
		},
	}

	// Clean up resources with "terraform destroy" at the end of the test
	defer terraform.Destroy(t, terraformOptions)

	// Run "terraform init" and "terraform apply". Fail the test if there are any errors.
	terraform.InitAndApply(t, terraformOptions)

	// Check if the S3 bucket exists
	sess, err := session.NewSession(&aws.Config{
		Region:   aws.String("us-east-1"),
		Endpoint: aws.String("http://localhost:4566"),
	})
	if err != nil {
		log.Fatalf("Failed to create session: %v", err)
	}

	s3Client := s3.New(sess)
	bucketName := terraform.Output(t, terraformOptions, "bucket_name")
	_, err = s3Client.HeadBucket(&s3.HeadBucketInput{
		Bucket: aws.String(bucketName),
	})

	assert.NoError(t, err, "Bucket should exist")
}

Folder Template:

    ├── README.md
    ├── build.sh
    ├── docker-compose.yml
    ├── terraform
    │   ├── main.tf
    │   ├── output.tf
    │   ├── s3.tf
    │   ├── terraform.tfstate
    │   ├── terraform.tfstate.backup
    │   └── variables.tf
    └── test
        ├── go.mod
        ├── go.sum
        └── s3_test.go

Run testing with build.sh file which would included in CICD pipeline

    #!/bin/bash

    echo "starting localstack on docker"
    docker-compose up -d


    echo "running Unit Test for Terraform"
    export GO111MODULE=on
    cd test
    go mod init terraform/test
    go mod tidy
    go test -v -timeout 30m

Conclusion

Automated infrastructure testing is essential for maintaining the reliability, security, and performance of modern infrastructure. By adopting best practices and leveraging appropriate tools, organizations can ensure that their infrastructure is robust and can support the demands of their applications and services.