2 months ago
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This post was co-written with Ran Isenberg, Principal Software Architect at CyberArk and an AWS Serverless Hero.
Serverless architectures enable agility and simplified cloud resource management. Organizations embracing serverless architectures build robust, distributed cloud applications. As organizations grow and the number of development teams increases, maintaining architectural consistency, standardization, and governance across projects becomes crucial.
In this post, you will discover how CyberArk, a leading identity security company, efficiently implements serverless architecture governance, reduces duplicative efforts, and saves months of development time by codifying architectural blueprints. This approach helps to prevent redundant efforts and promotes uniform architectural standards, facilitating the seamless adoption of organizational best practices and governance across diverse teams.
Overview
The risk of duplicative efforts and architectural inconsistencies is particularly pronounced in large organizations, especially for requirements unrelated to specific business domains owned by individual teams. Diverse approaches to Infrastructure-as-Code, CI/CD, observability, and security can lead to inconsistent implementations across teams. Application developers should focus on delivering business value efficiently, rather than navigating the complexities of building and operating distributed architectures while adhering to organizational best practices. To achieve this, you need an approach that empowers developers and provides guardrails to ensure vetted architectural patterns are consistently applied. This solution should enable accelerated delivery without sacrificing agility and innovation.
Some organizations implement internal wiki consolidating architectural guidance. While well-intentioned, relying solely on documentation assumes development teams diligently follow the guidelines, which often requires manual validation and limits scalability. To overcome this limitation, organizations should adopt a scalable approach that codifies, automates, and promotes architectural best practices. This mechanism allows developers to focus on delivering business-domain value and drives standardized operational excellence, governance, and organizational policies adherence.
Introducing serverless blueprints
CyberArk engineering team had over 900 developers. It was looking for ways to ensure they build their serverless services based on vetted architectural and security best practices with fully automated governance controls enforcement. The solution came in the form of codified architecture blueprints and automated tooling.
Serverless architectures are composed using loosely coupled services, integrated based on the application requirements. Application developers use IaC tools such as AWS CDK and HashiCorp Terraform to define their serverless architectures and integration patterns. CyberArk has augmented the IaC with governance tools, such as cdk-nag, AWS Config, and AWS Control Tower. With these complementary tools in place, they’ve built serverless blueprints which include architectural definitions based on organizational best practices, as well as automatically applied governance controls
To illustrate this, consider a simple serverless architecture pattern. In this common pattern, an SQS queue serves as the event source for a Lambda function, which parses incoming messages and updates an Amazon S3 bucket.
Figure 1. A simple serverless architecture with SQS Queue, Lambda function, and S3 Bucket
While this pattern seems simple, turning it into an enterprise-ready service requires additional effort. You must consider aspects like resiliency, security, governance, observability, and coding best practices. Let’s examine several examples codified in architectural blueprints at CyberArk.
Error-handling best practices
Your services should be resilient. Retries can help to overcome occasional network hiccups, but you also need to handle scenarios when your function consistently fails to process particular messages (known as poison message) – for example, because of a code bug. This can lead to endless processing loops, data loss, and potential extra charges. To address this, a blueprint can implement a failure handling mechanism with a dead letter queue, alerting, and redrive. This pattern is straightforward to implement and adds extra resiliency to your architecture. It is also generic and does not contain any business domain code. This is a typical example of an architectural pattern that can be codified in a blueprint and reused across development teams.
Figure 2. The simple serverless architecture with added resiliency best practices
Security best practices
Another example is securing S3 buckets. Organizations must enforce S3 security best practices, such as enabling access logs, blocking public access, and enabling encryption at rest. Codifying these guardrails in architectural blueprints adds an extra layer that allows your developers to comply with organization standards without having to explicitly implement adherence to each best practice and policy on their own.
Figure 3. The simple serverless architecture with added security best practices
The following code snippet uses AWS CDK to create an S3 bucket with common best practices:
- Enables bucket versioning on production environments only to save costs in non-production environments
- Enforces data encryption with AWS-managed keys.
- Blocks all public access
- Enforces SSL to block all non-secure-transport access
- Enables access logs
Additional security best practices you can codify in your blueprints include the principle of least privilege access, VPC-attachment, and code signing for sensitive Lambda functions, and using KMS keys for encryption.
Lambda best practices
Your Lambda functions are another example of where blueprints can help. By providing a function blueprint implementing the baseline for capabilities like observability, idempotency, and batch processing out-of-the-box, you enable developers to focus on their business domain code.
Figure 4. Layered view of a Lambda function in CyberArk’s serverless architecture blueprint
CyberArk embeds Powertools for AWS Lambda, a toolkit that implements serverless best practices to increase developer velocity, into their blueprints. The following code snippets embed Powertools for enabling enhanced observability and implementing batch processing.
# CDK code lambda_function = lambda.Function( environment={ constants.POWERTOOLS_SERVICE_NAME: constants.SERVICE_NAME, constants.POWER_TOOLS_LOG_LEVEL: 'INFO', }, tracing=lambda.Tracing.ACTIVE, layers=["powertools-layer"], log_format=lambda.LogFormat.JSON.value, system_log_level=lambda.SystemLogLevel.INFO.value # redacted ) # Function handler code processor = BatchProcessor(event_type=EventType.SQS, model=OrderSqsRecord) @logger.inject_lambda_context @metrics.log_metrics @tracer.capture_lambda_handler(capture_response=False) def lambda_handler(event, context: LambdaContext): return process_partial_response( event=event, record_handler=record_handler, processor=processor, context=context, )Governance controls
Blueprints are not static; they evolve as you adopt new best practices and governance policies. Developers start with a vetted blueprint but can deviate as they evolve their serverless apps. To enable continuous adherence, it is important to use a combination of organizational governance tools, such as AWS Control Tower and Service Control Policies, and architecture blueprints that embed governance controls automatically enforced by CI/CD. This ensures that any architectural modification will be validated for adhering to organizational standards.
AWS defines proactive controls as mechanisms that prevent developers from deploying resources that violate governance policies. Detective controls are mechanisms that detect, log, and alert on resource or configuration changes that violate governance policies.
Figure 5. Applying governance controls at all stages of CI/CD
Depending on the IaC tool, you can leverage different types of governance tools for proactive control enforcement. The following screenshot shows a proactive control violation identified during CI/CD via the cdk-nag framework. You can see cdk-nag throwing an error for the stack deployment due to Lambda execution role being assigned wild-card permissions.
Figure 6. Exception thrown by cdk-nag for using wildcard permissions
See the practical guide for implementing serverless governance.
Sample code
Ran Isenberg has open-sourced a sample Lambda Handler Cookbook blueprint illustrating some of the patterns CyberArk has adopted.
Additional serverless architecture patterns you might consider implementing in your blueprints are server-side encryption for an Amazon SNS topic with an encrypted Amazon SQS queue subscribed, auto-adjusting provisioned concurrency for Lambda functions, secure Serverless Aurora Cluster with bastion host, and more.
See more patterns implemented at serverlessland.com and cdkpatterns.com
Conclusion
Translating architectural and security best practices into modular IaC definitions, such as CDK constructs or Terraform modules, is a scalable and reusable technique that allows CyberArk to reduce duplicative efforts and save months of development time. Using IaC tools like AWS CDK or Terraform, augmented with governance tools like cdk-nag or checkov, enabled CyberArk to share implementation best practices and encode governance policies into architectural blueprints. Development teams adopting these blueprints do not need to reinvent the wheel, each trying to solve the same problem on their own. Instead, they leverage the knowledge codified in the blueprint.