The best way to provision cloud infrastructure is through code. Rather than opting for manual approaches, businesses are now more inclined to use the resources provided by Amazon Web Services (AWS).
While AWS tools such as Terraform and CloudFormation are certainly useful; however, using them to define your cloud resources can be challenging for developers because of the maintenance of large templates to keep the infrastructure code updated.
Fortunately, there is one other tool that can make the job easier: the AWS CDK. If you’re not familiar with this framework, we’ve got you covered. This is your guide to AWS CDK and how it works.
What is AWS CDK?
The Amazon Web Services Cloud Development kit or AWS CDK is a valuable tool that can be used to provision and define your cloud infrastructure using code. Moreover, it also helps with the deployment of the cloud architecture via AWS CloudFormation.
Despite being developed four years ago, it wasn’t until December of 2021 that AWS CDK became generally available for use.
The Concept Behind AWS CDK
Now that you know what the AWS Cloud Development Kit really is, let’s learn the concept behind it. Simply speaking, the AWS CDK was designed based on three major components. And because of these building blocks, the customization of infrastructure provisioning has been made possible. These include the following:
Think of the app as the foundation of the framework. All stacks and constructs are consolidated into one application. Afterward, the application can be used for deployment on the AWS cloud.
Stack is a single unit template, similar to a CloudFormation stack. It is responsible for holding all AWS resources. Only the resources are held in the form of constructs. These constructs can then be used for deployment.
Whether it is a single AWS resource or a combination of multiple AWS resources, the construct can retain both. Moreover, in each construct, you can build or combine AWS resources however you want.
Top Features of AWS CDK
In order to control and automate the AWS infrastructure, the AWS CDK is a vital tool for developers. Not only do you get the flexibility of developing AWS resources with your own tools, but it also enables iteration, which is much faster than CloudFormation. Furthermore, with CDK, all projects have become open source. Consequently, customers can make their contributions to enhance the future developments of CloudFormation.
That being said, here is a list of the top features of AWS CDK that can help you improve the development cycle considerably:
- Supports Multiple Programming Languages
As mentioned earlier, the AWS CDK is capable of supporting several programming languages, including:
- Use of Personal Development Tools
Another redeeming feature of the AWS CDK is that it allows developers to use their own tools to enhance the quality of codes used in AWS CDK projects.
- Use of Construct Hub for Utilizing CDK Constructs
When reinventing new resources for a project, there is no need to start from scratch. Instead, you can use the construct hub, where you can find different CDK constructs that can be shared for development purposes.
- Storage and Deployment Under One App
One of the most useful features of the AWS CDK is that it enables the deployment and storage of infrastructure, application, and configuration inside a single repository that falls under one CDK app.
- Open Source
As you already know by now, CDK is open source. And because of this, it allows users to contribute to the development and give feedback to developers, which also promotes growth.
- Generates CloudFormation Templates
You can easily generate CloudFormation templates containing more than a thousand lines with some lines from the Typescript coding language.
- Creates Recursive Functions
AWS CDK has the ability to create functions repeatedly. As a result, you can easily create multiple AWS resources without having to perform the same function every time. All functions are reiterated automatically.
Since this is a complete guide to AWS CDK and how it works, it is essential that you also learn about its best practices. Now that we’re done with the features, here is a summary of all the best practices you can employ to manage codes, pipelines, constructs, and environments:
- Implement a Landing Zone
Implementing a landing zone strategy is the best way to organize AWS accounts. A landing zone strategy helps users focus on the core of their businesses with the help of automation. Using this strategy, you can set up cloud environments quickly and efficiently.
When you implement a landing zone strategy, it automates all guardrails and security policies. Consequently, the configuration and onboarding of new teams and accounts are executed swiftly without any delays.
- Create Several Stages
By creating several AWS accounts or stages, build changes via AWS CDK apps are enabled. Some of the examples of these stages include but aren’t limited to:
- Test Staging
- Incorporate Integration Tests
Incorporating integration tests in pipelines eliminates the possibility of breaking changes to the application.
Note: Integration tests are automated.
- Inspect AWS Resources
Inspecting all AWS resources before they are deployed in production is essential. The best practice for reviewing the resources is to use the cdk diff command. This command conducts a detailed comparison of the already-deployed CloudFormation template with another CloudFormation template equivalent to the current code. After analysis, all the differences are displayed.
- Keep Stateful and Stateless Constructs Separate
It’s not recommended to keep stateful and stateless constructs together. Instead, using separate stacks for both is considered the best practice. In the case of stateful constructs, the termination protection can be switched on. It allows you to create or destroy several copies of the stateless stacks without losing any data.
Another reason for segregating stateless and stateful stacks is because stateful resources are more prone to renaming. When a construct is renamed, it can replace the resource entirely. So, the only viable solution is to keep both stacks separated, as the stateful constructs are likely to be renamed or moved. Some examples of stateful constructs include databases and storage, while monitoring, ECS, and API fall under the category of stateless constructs.
- Avoid Using CloudFormation Logic
When representing a construct at the time of synthesis, it is recommended to use the conditions of the programming language used. The use of AWS CloudFormation logic should be avoided.
Some Useful Tools for AWS CDK
Even with AWS CDK, you still need additional tools to reduce the development time and improve workflows. Plus, having suitable tools at hand can considerably increase code quality. Here is a list of our top picks of tools that can be helpful when using AWS CDK:
- AWS Toolkit
The AWS Toolkit is an extension that makes building and interaction on the AWS more efficient and productive. Some of the features of this tool include:
Using the VS code, the AWS Explorer allows you to get instant access to any AWS Service on your account. To elaborate, it locates the resources in the active region and allows you to view the contents in the VS code directly.
It’s a time-saving solution that eliminates manual effort. Ordinarily, you would have to log onto the AWS Console and manually look for the resources to view results, but with AWS Explorer, all these steps are not required.
The CDK Explorer lets you view the interconnectivity of the components on the AWS CDK app. The tree view is easy to follow.
Amazon CloudWatch Logs
With this feature, you can easily view CloudWatch logs along with their time-stamps. Most of the logs are in real-time, allowing you to load the most recent 10,000 lines.
Projen is a useful tool that functions as a project generator. It initiates pre-configured and new projects using best practices. Generally, managing and transferring project configuration files to new projects can be challenging. That’s where Projen comes in. It lets you synthesize project configuration files that have been written in TypeScript.
Eslint is a valuable tool used for identifying and reporting patterns found in code. Simply put, it analyzes your code and highlights problems based on the set of rules that have been pre-configured. It helps make the code more consistent and ensures there aren’t any bugs.
- Visual Studio IntelliCode
When building constructs, the Visual Studio IntelliCode extension provides assistance with code completion using Artificial Intelligence (AI). It is capable of picking up references and using that information, the tool types and auto-completes the code.
Simply put, it’s a valuable tool that helps developers with code completion.
Cdk-nag is a tool you can find in the construction hub. It is used to check CDK applications for best practices. However, the analysis is conducted based on the available pack of rules. When you use cdk-nag to evaluate the best practices, it helps you make your code more secure. Generally, it is recommended to use this tool on CI or CD pipelines. It helps reinforce standards on all of your built and deployed AWS resources.
AWS CDK vs. AWS CloudFormation
The AWS CDK and AWS CloudFormation are both IaS, i.e., Infrastructure as Code. While IaS is essential for cloud development, CDK is much better in terms of speed, performance, and automation.
You can think of AWS CDK as a transpiler of the CloudFormation, meaning it can generate codes out of it without wasting time or needless effort.
Moreover, with AWS CloudFormation, you have to declare resources using YAML or JSON. However, with AWS CDK, you can use any programming language of choice to define your infrastructure. Another advantage of the CDK is that it helps you learn the programming language, which can also be used in other job applications. On the other hand, writing YAML is not only time-consuming, but it is of no use elsewhere.
That being said, it is essential first to understand CloudFormation to use the CDK effectively. If your underlying concepts are unclear, it will directly have an impact on your progress. Consequently, you will spend more time debugging and understanding why things aren’t working out as you planned.
The Bottom Line
We hope this guide to AWS CDK and how it works helped you in understanding its features and benefits. When you adopt the AWS CDK, it will automatically improve your development cycle. Plus, it offers considerable advantages over AWS CloudFormation.
But it is essential to use the best practices and tools mentioned above to prevent delays in the development and deployment of resources. Moreover, it helps eliminate potential issues in the code.
Considering all the benefits, the Amazon Web Services Cloud Development Kit is being adopted all over the world at a rapid pace. Despite being around for such a short period, the AWS CDK community has evolved considerably. And there is little doubt that this open source project is here to stay for many years to come. So, it would be safe to say that this framework will only continue to soar to greater heights with more and more developers joining the community.
Since it combines the experience and expertise of developers all over the world, it will turn into a solid framework that will become a solid solution for defining cloud application resources with the coding language of preference.
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