configuration management Archives - Online Code Generator

The history and future roadmap of the AWS CloudFormation Registry

Posted on May 4, 2023May 21, 2023 by Mark FeehilyComments Off

AWS CloudFormation is an Infrastructure as Code (IaC) service that allows you to model your cloud resources in template files that can be authored or generated in a variety of languages. You can manage stacks that deploy those resources via the AWS Management Console, the AWS Command Line Interface (AWS CLI), or the API. CloudFormation helps customers to quickly and consistently deploy and manage cloud resources, but like all IaC tools, it faced challenges keeping up with the rapid pace of innovation of AWS services. In this post, we will review the history of the CloudFormation registry, which is the result of a strategy we developed to address scaling and standardization, as well as integration with other leading IaC tools and partner products. We will also give an update on the current state of CloudFormation resource coverage and review the future state, which has a goal of keeping CloudFormation and other IaC tools up to date with the latest AWS services and features.

History

The CloudFormation service was first announced in February of 2011, with sample templates that showed how to deploy common applications like blogs and wikis. At launch, CloudFormation supported 13 out of 15 available AWS services with 48 total resource types. At first, resource coverage was tightly coupled to the core CloudFormation engine, and all development on those resources was done by the CloudFormation team itself. Over the past decade, AWS has grown at a rapid pace, and there are currently 200+ services in total. A challenge over the years has been the coverage gap between what was possible for a customer to achieve using AWS services, and what was possible to define in a CloudFormation template.

It became obvious that we needed a change in strategy to scale resource development in a way that could keep up with the rapid pace of innovation set by hundreds of service teams delivering new features on a daily basis. Over the last decade, our pace of innovation has increased nearly 40-fold, with 80 significant new features launched in 2011 versus more than 3,000 in 2021. Since CloudFormation was a key adoption driver (or blocker) for new AWS services, those teams needed a way to create and manage their own resources. The goal was to enable day one support of new services at the time of launch with complete CloudFormation resource coverage.

In 2016, we launched an internal self-service platform that allowed service teams to control their own resources. This began to solve the scaling problems inherent in the prior model where the core CloudFormation team had to do all the work themselves. The benefits went beyond simply distributing developer effort, as the service teams have deep domain knowledge on their products, which allowed them to create more effective IaC components. However, as we developed resources on this model, we realized that additional design features were needed, such as standardization that could enable automatic support for features like drift detection and resource imports.

We embarked on a new project to address these concerns, with the goal of improving the internal developer experience as well as providing a public registry where customers could use the same programming model to define their own resource types. We realized that it wasn’t enough to simply make the new model available—we had to evangelize it with a training campaign, conduct engineering boot-camps, build better tooling like dashboards and deployment pipeline templates, and produce comprehensive on-boarding documentation. Most importantly, we made CloudFormation support a required item on the feature launch checklist for new services, a requirement that goes beyond documentation and is built into internal release tooling (exceptions to this requirement are rare as training and awareness around the registry have improved over time). This was a prime example of one of the maxims we repeat often at Amazon: good mechanisms are better than good intentions.

In 2019, we made this new functionality available to customers when we announced the CloudFormation registry, a capability that allowed developers to create and manage private resource types. We followed up in 2021 with the public registry where third parties, such as partners in the AWS Partner Network (APN), can publish extensions. The open source resource model that customers and partners use to publish third-party registry extensions is the same model used by AWS service teams to provide CloudFormation support for their features.

Once a service team on-boards their resources to the new resource model and builds the expected Create, Read, Update, Delete, and List (CRUDL) handlers, managed experiences like drift detection and resource import are all supported with no additional development effort. One recent example of day-1 CloudFormation support for a popular new feature was Lambda Function URLs, which offered a built-in HTTPS endpoint for single-function micro-services. We also migrated the Amazon Relational Database Service (Amazon RDS) Database Instance resource (AWS::RDS::DBInstance) to the new resource model in September 2022, and within a month, Amazon RDS delivered support for Amazon Aurora Serverless v2 in CloudFormation. This accelerated delivery is possible because teams can now publish independently by taking advantage of the de-centralized Registry ownership model.

Current State

We are building out future innovations for the CloudFormation service on top of this new standardized resource model so that customers can benefit from a consistent implementation of event handlers. We built AWS Cloud Control API on top of this new resource model. Cloud Control API takes the Create-Read-Update-Delete-List (CRUDL) handlers written for the new resource model and makes them available as a consistent API for provisioning resources. APN partner products such as HashiCorp Terraform, Pulumi, and Red Hat Ansible use Cloud Control API to stay in sync with AWS service launches without recurring development effort.

Figure 1. Cloud Control API Resource Handler Diagram

Besides 3rd party application support, the public registry can also be used by the developer community to create useful extensions on top of AWS services. A common solution to extending the capabilities of CloudFormation resources is to write a custom resource, which generally involves inline AWS Lambda function code that runs in response to CREATE, UPDATE, and DELETE signals during stack operations. Some of those use cases can now be solved by writing a registry extension resource type instead. For more information on custom resources and resource types, and the differences between the two, see Managing resources using AWS CloudFormation Resource Types.

CloudFormation Registry modules, which are building blocks authored in JSON or YAML, give customers a way to replace fragile copy-paste template reuse with template snippets that are published in the registry and consumed as if they were resource types. Best practices can be encapsulated and shared across an organization, which allows infrastructure developers to easily adhere to those best practices using modular components that abstract away the intricate details of resource configuration.

CloudFormation Registry hooks give security and compliance teams a vital tool to validate stack deployments before any resources are created, modified, or deleted. An infrastructure team can activate hooks in an account to ensure that stack deployments cannot avoid or suppress preventative controls implemented in hook handlers. Provisioning tools that are strictly client-side do not have this level of enforcement.

A useful by-product of publishing a resource type to the public registry is that you get automatic support for the AWS Cloud Development Kit (CDK) via an experimental open source repository on GitHub called cdk-cloudformation. In large organizations it is typical to see a mix of CloudFormation deployments using declarative templates and deployments that make use of the CDK in languages like TypeScript and Python. By publishing re-usable resource types to the registry, all of your developers can benefit from higher level abstractions, regardless of the tool they choose to create and deploy their applications. (Note that this project is still considered a developer preview and is subject to change)

If you want to see if a given CloudFormation resource is on the new registry model or not, check if the provisioning type is either Fully Mutable or Immutable by invoking the DescribeType API and inspecting the ProvisioningType response element.

Here is a sample CLI command that gets a description for the AWS::Lambda::Function resource, which is on the new registry model.

$ aws cloudformation describe-type –type RESOURCE
–type-name AWS::Lambda::Function | grep ProvisioningType

“ProvisioningType”: “FULLY_MUTABLE”,

The difference between FULLY_MUTABLE and IMMUTABLE is the presence of the Update handler. FULLY_MUTABLE types includes an update handler to process updates to the type during stack update operations. Whereas, IMMUTABLE types do not include an update handler, so the type can’t be updated and must instead be replaced during stack update operations. Legacy resource types will be NON_PROVISIONABLE.

Opportunities for improvement

As we continue to strive towards our ultimate goal of achieving full feature coverage and a complete migration away from the legacy resource model, we are constantly identifying opportunities for improvement. We are currently addressing feature gaps in supported resources, such as tagging support for EC2 VPC Endpoints and boosting coverage for resource types to support drift detection, resource import, and Cloud Control API. We have fully migrated more than 130 resources, and acknowledge that there are many left to go, and the migration has taken longer than we initially anticipated. Our top priority is to maintain the stability of existing stacks—we simply cannot break backwards compatibility in the interest of meeting a deadline, so we are being careful and deliberate. One of the big benefits of a server-side provisioning engine like CloudFormation is operational stability—no matter how long ago you deployed a stack, any future modifications to it will work without needing to worry about upgrading client libraries. We remain committed to streamlining the migration process for service teams and making it as easy and efficient as possible.

The developer experience for creating registry extensions has some rough edges, particularly for languages other than Java, which is the language of choice on AWS service teams for their resource types. It needs to be easier to author schemas, write handler functions, and test the code to make sure it performs as expected. We are devoting more resources to the maintenance of the CLI and plugins for Python, Typescript, and Go. Our response times to issues and pull requests in these and other repositories in the aws-cloudformation GitHub organization have not been as fast as they should be, and we are making improvements. One example is the cloudformation-cli repository, where we have merged more than 30 pull requests since October of 2022.

To keep up with progress on resource coverage, check out the CloudFormation Coverage Roadmap, a GitHub project where we catalog all of the open issues to be resolved. You can submit bug reports and feature requests related to resource coverage in this repository and keep tabs on the status of open requests. One of the steps we took recently to improve responses to feature requests and bugs reported on GitHub is to create a system that converts GitHub issues into tickets in our internal issue tracker. These tickets go directly to the responsible service teams—an example is the Amazon RDS resource provider, which has hundreds of merged pull requests.

We have recently announced a new GitHub repository called community-registry-extensions where we are managing a namespace for public registry extensions. You can submit and discuss new ideas for extensions and contribute to any of the related projects. We handle the testing, validation, and deployment of all resources under the AwsCommunity:: namespace, which can be activated in any AWS account for use in your own templates.

To get started with the CloudFormation registry, visit the user guide, and then dive in to the detailed developer guide for information on how to use the CloudFormation Command Line Interface (CFN-CLI) to write your own resource types, modules, and hooks.

We recently created a new Discord server dedicated to CloudFormation. Please join us to ask questions, discuss best practices, provide feedback, or just hang out! We look forward to seeing you there.

Conclusion

In this post, we hope you gained some insights into the history of the CloudFormation registry, and the design decisions that were made during our evolution towards a standardized, scalable model for resource development that can be shared by AWS service teams, customers, and APN partners. Some of the lessons that we learned along the way might be applicable to complex design initiatives at your own company. We hope to see you on Discord and GitHub as we build out a rich set of registry resources together!

About the authors:

Eric Beard

Eric is a Solutions Architect at Amazon Web Services in Seattle, Washington, where he leads the field specialist group for Infrastructure as Code. His technology career spans two decades, preceded by service in the United States Marine Corps as a Russian interpreter and arms control inspector.

Rahul Sharma

Rahul is a Senior Product Manager-Technical at Amazon Web Services with over two years of product management spanning AWS CloudFormation and AWS Cloud Control API.

Using GitHub Actions with Amazon CodeCatalyst

Posted on February 8, 2023May 21, 2023 by Mark FeehilyComments Off

An Amazon CodeCatalyst workflow is an automated procedure that describes how to build, test, and deploy your code as part of a continuous integration and continuous delivery (CI/CD) system. You can use GitHub Actions alongside native CodeCatalyst actions in a CodeCatalyst workflow.

Introduction:

In a prior post in this series, Using Workflows to Build, Test, and Deploy with Amazon CodeCatalyst, I discussed creating CI/CD pipelines in CodeCatalyst and how that relates to The Unicorn Project’s main protagonist, Maxine. CodeCatalyst workflows help you reliably deliver high-quality application updates frequently, quickly, and securely. CodeCatalyst allows you to quickly assemble and configure actions to compose workflows that automate your CI/CD pipeline, test reporting, and other manual processes. Workflows use provisioned compute, Lambda compute, custom container images, and a managed build infrastructure to scale execution easily without sacrificing flexibility. In this post, I will return to workflows and discuss running GitHub Actions alongside native CodeCatalyst actions.

Prerequisites

If you would like to follow along with this walkthrough, you will need to:

Have an AWS Builder ID for signing in to CodeCatalyst.
Belong to a space and have the space administrator role assigned to you in that space. For more information, see Creating a space in CodeCatalyst, Managing members of your space, and Space administrator role.
Have an AWS account associated with your space and have the IAM role in that account. For more information about the role and role policy, see Creating a CodeCatalyst service role.

Walkthrough

As with the previous posts in the CodeCatalyst series, I am going to use the Modern Three-tier Web Application blueprint. Blueprints provide sample code and CI/CD workflows to help you get started easily across different combinations of programming languages and architectures. To follow along, you can re-use a project you created previously, or you can refer to a previous post that walks through creating a project using the Three-tier blueprint.

As the team has grown, I have noticed that code quality has decreased. Therefore, I would like to add a few additional tools to validate code quality when a new pull request is submitted. In addition, I would like to create a Software Bill of Materials (SBOM) for each pull request so I know what components are used by the code. In the previous post on workflows, I focused on the deployment workflow. In this post, I will focus on the OnPullRequest workflow. You can view the OnPullRequest pipeline by expanding CI/CD from the left navigation, and choosing Workflows. Next, choose OnPullRequest and you will be presented with the workflow shown in the following screenshot. This workflow runs when a new pull request is submitted and currently uses Amazon CodeGuru to perform an automated code review.

Figure 1. OnPullRequest Workflow with CodeGuru code review

While CodeGuru provides intelligent recommendations to improve code quality, it does not check style. I would like to add a linter to ensure developers follow our coding standards. While CodeCatalyst supports a rich collection of native actions, this does not currently include a linter. Fortunately, CodeCatalyst also supports GitHub Actions. Let’s use a GitHub Action to add a linter to the workflow.

Select Edit in the top right corner of the Workflow screen. If the editor opens in YAML mode, switch to Visual mode using the toggle above the code. Next, select “+ Actions” to show the list of actions. Then, change from Amazon CodeCatalyst to GitHub using the dropdown. At the time this blog was published, CodeCatalyst includes about a dozen curated GitHub Actions. Note that you are not limited to the list of curated actions. I’ll show you how to add GitHub Actions that are not on the list later in this post. For now, I am going to use Super-Linter to check coding style in pull requests. Find Super-Linter in the curated list and click the plus icon to add it to the workflow.

Figure 2. Super-Linter action with add icon

This will add a new action to the workflow and open the configuration dialog box. There is no further configuration needed, so you can simply close the configuration dialog box. The workflow should now look like this.

Figure 3. Workflow with the new Super-Linter action

Notice that the actions are configured to run in parallel. In the previous post, when I discussed the deployment workflow, the steps were sequential. This made sense since each step built on the previous step. For the pull request workflow, the actions are independent, and I will allow them to run in parallel so they complete faster. I select Validate, and assuming there are no issues, I select Commit to save my changes to the repository.

While CodeCatalyst will start the workflow when a pull request is submitted, I do not have a pull request to submit. Therefore, I select Run to test the workflow. A notification at the top of the screen includes a link to view the run. As expected, Super Linter fails because it has found issues in the application code. I click on the Super Linter action and review the logs. Here are few issues that Super Linter reported regarding app.py used by the backend application. Note that the log has been modified slightly to fit on a single line.

/app.py:2:1: F401 ‘os’ imported but unused
/app.py:2:1: F401 ‘time’ imported but unused
/app.py:2:1: F401 ‘json’ imported but unused
/app.py:2:10: E401 multiple imports on one line
/app.py:4:1: F401 ‘boto3’ imported but unused
/app.py:6:9: E225 missing whitespace around operator
/app.py:8:1: E402 module level import not at top of file
/app.py:10:1: E402 module level import not at top of file
/app.py:15:35: W291 trailing whitespace
/app.py:16:5: E128 continuation line under-indented for visual indent
/app.py:17:5: E128 continuation line under-indented for visual indent
/app.py:25:5: E128 continuation line under-indented for visual indent
/app.py:26:5: E128 continuation line under-indented for visual indent
/app.py:33:12: W292 no newline at end of file

With Super-Linter working, I turn my attention to creating a Software Bill of Materials
(SBOM). I am going to use OWASP CycloneDX to create the SBOM. While there is a GitHub Action for CycloneDX, at the time I am writing this post, it is not available from the list of curated GitHub Actions in CodeCatalyst. Fortunately, CodeCatalyst is not limited to the curated list. I can use most any GitHub Action in CodeCatalyst. To add a GitHub Action that is not in the curated list, I return to edit mode, find GitHub Actions in the list of curated actions, and click the plus icon to add it to the workflow.

Figure 4. GitHub Action with add icon

CodeCatalyst will add a new action to the workflow and open the configuration dialog box. I choose the Configuration tab and use the pencil icon to change the Action Name to Software-Bill-of-Materials. Then, I scroll down to the configuration section, and change the GitHub Action YAML. Note that you can copy the YAML from the GitHub Actions Marketplace, including the latest version number. In addition, the CycloneDX action expects you to pass the path to the Python requirements file as an input parameter.

Figure 5. GitHub Action YAML configuration

Since I am using the generic GitHub Action, I must tell CodeCatalyst which artifacts are produced by the action and should be collected after execution. CycloneDX creates an XML file called bom.xml which I configure as an artifact. Note that a CodeCatalyst artifact is the output of a workflow action, and typically consists of a folder or archive of files. You can share artifacts with subsequent actions.

Figure 6. Artifact configuration with the path to bom.xml

Once again, I select Validate, and assuming there are no issues, I select Commit to save my changes to the repository. I now have three actions that run in parallel when a pull request is submitted: CodeGuru, Super-Linter, and Software Bill of Materials.

Figure 7. Workflow including the software bill of materials

As before, I select Run to test my workflow and click the view link in the notification. As expected, the workflow fails because Super-Linter is still reporting issues. However, the new Software Bill of Materials has completed successfully. From the artifacts tab I can download the SBOM.

Figure 8. Artifacts tab listing code review and SBOM

The artifact is a zip archive that includes the bom.xml created by CycloneDX. This includes, among other information, a list of components used in the backend application.

<components>
<component type=”library” bom-ref=”7474f0f6-8aa2-46db-bebf-a7648cff84e1″>
<name>Jinja2</name>
<version>3.1.2</version>
<purl>pkg:pypi/[email protected]</purl>
</component>
<component type=”library” bom-ref=”fad0708b-d007-4f98-a80c-056b136015df”>
<name>aws-cdk-lib</name>
<version>2.43.0</version>
<purl>pkg:pypi/[email protected]</purl>
</component>
<component type=”library” bom-ref=”23e3aaae-b4e1-4f3b-b026-fcd298c9cb9b”>
<name>aws-cdk.aws-apigatewayv2-alpha</name>
<version>2.43.0a0</version>
<purl>pkg:pypi/[email protected]</purl>
</component>
<component type=”library” bom-ref=”d283cf17-9125-422c-b55c-cabb64d18f79″>
<name>aws-cdk.aws-apigatewayv2-integrations-alpha</name>
<version>2.43.0a0</version>
<purl>pkg:pypi/a[email protected]</purl>
</component>
<component type=”library” bom-ref=”0f095c84-c9e9-4d6c-a4ed-c4a6c7605426″>
<name>aws-cdk.aws-lambda-python-alpha</name>
<version>2.43.0a0</version>
<purl>pkg:pypi/[email protected]</purl>
</component>
<component type=”library” bom-ref=”b248b85b-ba27-4796-bcdf-6bd82ad47295″>
<name>constructs</name>
<version>>=10.0.0,<11.0.0</version>
<purl>pkg:pypi/constructs@%3E%3D10.0.0%2C%3C11.0.0</purl>
</component>
<component type=”library” bom-ref=”72b1da33-19c2-4b5c-bd58-7f719dafc28a”>
<name>simplejson</name>
<version>3.17.6</version>
<purl>pkg:pypi/[email protected]</purl>
</component>
</components>

The workflow is now enforcing code quality and generating a SBOM like I wanted. Note that while this is a great start, there is still room for improvement. First, I could collect reports generated by the actions in my workflow, and define success criteria for code quality. Second, I could scan the SBOM for known security vulnerabilities using a Software Composition Analysis (SCA) solution. I will be covering this in a future post in this series.

Cleanup

If you have been following along with this workflow, you should delete the resources you deployed so you do not continue to incur charges. First, delete the two stacks that CDK deployed using the AWS CloudFormation console in the AWS account you associated when you launched the blueprint. These stacks will have names like mysfitsXXXXXWebStack and mysfitsXXXXXAppStack. Second, delete the project from CodeCatalyst by navigating to Project settings and choosing Delete project.

Conclusion

In this post, you learned how to add GitHub Actions to a CodeCatalyst workflow. I used GitHub Actions alongside native CodeCatalyst actions in my workflow. I also discussed adding actions from both the curated list of actions and others not in the curated list. Read the documentation to learn more about using GitHub Actions in CodeCatalyst.

About the authors:

Dr. Rahul Gaikwad

Dr. Rahul is a DevOps Lead Consultant at AWS. He helps customers to migrate and modernize workloads to AWS Cloud with a special focus on DevOps and IaC. He is passionate about building innovative solutions using technology and enjoys collaborating with customers and peers. He contributes to open-source community projects. Outside of work, Rahul has completed Ph.D. in AIOps and he enjoys travelling and spending time with his family.

Anirudh Sharma

Anirudh is a Cloud Support Engineer 2 with an extensive background in DevOps offerings at AWS, he is also a Subject Matter Expert in AWS ElasticBeanstalk and AWS CodeDeploy services. He loves helping customers and learning new services and technologies. He also loves travelling and has a goal to visit Japan someday, is a Golden State Warriors fan and loves spending time with his family.

Navdeep Pareek

Navdeep is Lead Migration Consultant at AWS. He helps customer to migrate and modernize customer workloads to AWS Cloud and have specialisation in automation, DevOps. In his spare time, he enjoys travelling, cooking and spending time with family and friends.

Manually Approving Security Changes in CDK Pipeline

Posted on January 18, 2023May 21, 2023 by Mark FeehilyComments Off

In this post I will show you how to add a manual approval to AWS Cloud Development Kit (CDK) Pipelines to confirm security changes before deployment. With this solution, when a developer commits a change, CDK pipeline identifies an IAM permissions change, pauses execution, and sends a notification to a security engineer to manually approve or reject the change before it is deployed.

Introduction

In my role I talk to a lot of customers that are excited about the AWS Cloud Development Kit (CDK). One of the things they like is that L2 constructs often generate IAM and other security policies. This can save a lot of time and effort over hand coding those policies. Most customers also tell me that the policies generated by CDK are more secure than the policies they generate by hand.

However, these same customers are concerned that their security engineering team does not know what is in the policies CDK generates. In the past, these customers spent a lot of time crafting a handful of IAM policies that developers can use in their apps. These policies were well understood, but overly permissive because they were often reused across many applications.

Customers want more visibility into the policies CDK generates. Luckily CDK provides a mechanism to approve security changes. If you are using CDK, you have probably been prompted to approve security changes when you run cdk deploy at the command line. That works great on a developer’s machine, but customers want to build the same confirmation into their continuous delivery pipeline. CDK provides a mechanism for this with the ConfirmPermissionsBroadening action. Note that ConfirmPermissionsBroadening is only supported by the AWS CodePipline deployment engine.

Background

Before I talk about ConfirmPermissionsBroadening, let me review how CDK creates IAM policies. Consider the “Hello, CDK” application created in AWS CDK Workshop. At the end of this module, I have an AWS Lambda function and an Amazon API Gateway defined by the following CDK code.

// defines an AWS Lambda resource
const hello = new lambda.Function(this, ‘HelloHandler’, {
runtime: lambda.Runtime.NODEJS_14_X, // execution environment
code: lambda.Code.fromAsset(‘lambda’), // code loaded from “lambda” directory
handler: ‘hello.handler’ // file is “hello”, function is “handler”
});

// defines an API Gateway REST API resource backed by our “hello” function.
new apigw.LambdaRestApi(this, ‘Endpoint’, {
handler: hello
});

Note that I did not need to define the IAM Role or Lambda Permissions. I simply passed a refence to the Lambda function to the API Gateway (line 10 above). CDK understood what I was doing and generated the permissions for me. For example, CDK generated the following Lambda Permission, among others.

{
“Effect”: “Allow”,
“Principal”: {
“Service”: “apigateway.amazonaws.com”
},
“Action”: “lambda:InvokeFunction”,
“Resource”: “arn:aws:lambda:us-east-1:123456789012:function:HelloHandler2E4FBA4D”,
“Condition”: {
“ArnLike”: {
“AWS:SourceArn”: “arn:aws:execute-api:us-east-1:123456789012:9y6ioaohv0/prod/*/”
}
}
}

Notice that CDK generated a narrowly scoped policy, that allows a specific API (line 10 above) to call a specific Lambda function (line 7 above). This policy cannot be reused elsewhere. Later in the same workshop, I created a Hit Counter Construct using a Lambda function and an Amazon DynamoDB table. Again, I associated them using a single line of CDK code.

table.grantReadWriteData(this.handler);

As in the prior example, CDK generated a narrowly scoped IAM policy. This policy allows the Lambda function to perform certain actions (lines 4-11) on a specific table (line 14 below).

{
“Effect”: “Allow”,
“Action”: [
“dynamodb:BatchGetItem”,
“dynamodb:ConditionCheckItem”,
“dynamodb:DescribeTable”,
“dynamodb:GetItem”,
“dynamodb:GetRecords”,
“dynamodb:GetShardIterator”,
“dynamodb:Query”,
“dynamodb:Scan”
],
“Resource”: [
“arn:aws:dynamodb:us-east-1:123456789012:table/HelloHitCounterHits”
]
}

As you can see, CDK is doing a lot of work for me. In addition, CDK is creating narrowly scoped policies for each resource, rather than sharing a broadly scoped policy in multiple places.

CDK Pipelines Permissions Checks

Now that I have reviewed how CDK generates policies, let’s discuss how I can use this in a Continuous Deployment pipeline. Specifically, I want to allow CDK to generate policies, but I want a security engineer to review any changes using a manual approval step in the pipeline. Of course, I don’t want security to be a bottleneck, so I will only require approval when security statements or traffic rules are added. The pipeline should skip the manual approval if there are no new security rules added.

Let’s continue to use CDK Workshop as an example. In the CDK Pipelines module, I used CDK to configure AWS CodePipeline to deploy the “Hello, CDK” application I discussed above. One of the last things I do in the workshop is add a validation test using a post-deployment step. Adding a permission check is similar, but I will use a pre-deployment step to ensure the permission check happens before deployment.

First, I will import ConfirmPermissionsBroadening from the pipelines package

import {ConfirmPermissionsBroadening} from “aws-cdk-lib/pipelines”;

Then, I can simply add ConfirmPermissionsBroadening to the deploySatage using the addPre method as follows.

const deploy = new WorkshopPipelineStage(this, ‘Deploy’);
const deployStage = pipeline.addStage(deploy);

deployStage.addPre(
new ConfirmPermissionsBroadening(“PermissionCheck”, {
stage: deploy
})

deployStage.addPost(
// Post Deployment Test Code Omitted
)

Once I commit and push this change, a new manual approval step called PermissionCheck.Confirm is added to the Deploy stage of the pipeline. In the future, if I push a change that adds additional rules, the pipeline will pause here and await manual approval as shown in the screenshot below.

Figure 1. Pipeline waiting for manual review

When the security engineer clicks the review button, she is presented with the following dialog. From here, she can click the URL to see a summary of the change I am requesting which was captured in the build logs. She can also choose to approve or reject the change and add comments if needed.

Figure 2. Manual review dialog with a link to the build logs

When the security engineer clicks the review URL, she is presented with the following sumamry of security changes.

Figure 3. Summary of security changes in the build logs

The final feature I want to add is an email notification so the security engineer knows when there is something to approve. To accomplish this, I create a new Amazon Simple Notification Service (SNS) topic and subscription and associate it with the ConfirmPermissionsBroadening Check.

// Create an SNS topic and subscription for security approvals
const topic = new sns.Topic(this, ‘SecurityApproval’);
topic.addSubscription(new subscriptions.EmailSubscription(‘[email protected]’));

deployStage.addPre(
new ConfirmPermissionsBroadening(“PermissionCheck”, {
stage: deploy,
notificationTopic: topic
})

With the notification configured, the security engineer will receive an email when an approval is needed. She will have an opportunity to review the security change I made and assess the impact. This gives the security engineering team the visibility they want into the policies CDK is generating. In addition, the approval step is skipped if a change does not add security rules so the security engineer does not become a bottle neck in the deployment process.

Conclusion

AWS Cloud Development Kit (CDK) automates the generation of IAM and other security policies. This can save a lot of time and effort but security engineering teams want visibility into the policies CDK generates. To address this, CDK Pipelines provides the ConfirmPermissionsBroadening action. When you add ConfirmPermissionsBroadening to your CI/CD pipeline, CDK will wait for manual approval before deploying a change that includes new security rules.

About the author:

Brian Beach

Brian Beach has over 20 years of experience as a Developer and Architect. He is currently a Principal Solutions Architect at Amazon Web Services. He holds a Computer Engineering degree from NYU Poly and an MBA from Rutgers Business School. He is the author of “Pro PowerShell for Amazon Web Services” from Apress. He is a regular author and has spoken at numerous events. Brian lives in North Carolina with his wife and three kids.

Multi-branch pipeline management and infrastructure deployment using AWS CDK Pipelines

Posted on January 14, 2023May 21, 2023 by Mark FeehilyComments Off

This post describes how to use the AWS CDK Pipelines module to follow a Gitflow development model using AWS Cloud Development Kit (AWS CDK). Software development teams often follow a strict branching strategy during a solutions development lifecycle. Newly-created branches commonly need their own isolated copy of infrastructure resources to develop new features.

CDK Pipelines is a construct library module for continuous delivery of AWS CDK applications. CDK Pipelines are self-updating: if you add application stages or stacks, then the pipeline automatically reconfigures itself to deploy those new stages and/or stacks.

The following solution creates a new AWS CDK Pipeline within a development account for every new branch created in the source repository (AWS CodeCommit). When a branch is deleted, the pipeline and all related resources are also destroyed from the account. This GitFlow model for infrastructure provisioning allows developers to work independently from each other, concurrently, even in the same stack of the application.

Solution overview

The following diagram provides an overview of the solution. There is one default pipeline responsible for deploying resources to the different application environments (e.g., Development, Pre-Prod, and Prod). The code is stored in CodeCommit. When new changes are pushed to the default CodeCommit repository branch, AWS CodePipeline runs the default pipeline. When the default pipeline is deployed, it creates two AWS Lambda functions.

These two Lambda functions are invoked by CodeCommit CloudWatch events when a new branch in the repository is created or deleted. The Create Lambda function uses the boto3 CodeBuild module to create an AWS CodeBuild project that builds the pipeline for the feature branch. This feature pipeline consists of a build stage and an optional update pipeline stage for itself. The Destroy Lambda function creates another CodeBuild project which cleans all of the feature branch’s resources and the feature pipeline.

Figure 1. Architecture diagram.

Prerequisites

Before beginning this walkthrough, you should have the following prerequisites:

An AWS account

AWS CDK installed

Python3 installed
Jq (JSON processor) installed
Basic understanding of continuous integration/continuous development (CI/CD) Pipelines

Initial setup

Download the repository from GitHub:

# Command to clone the repository
git clone https://github.com/aws-samples/multi-branch-cdk-pipelines.git
cd multi-branch-cdk-pipelines

Create a new CodeCommit repository in the AWS Account and region where you want to deploy the pipeline and upload the source code from above to this repository. In the config.ini file, change the repository_name and region variables accordingly.

Make sure that you set up a fresh Python environment. Install the dependencies:

pip install -r requirements.txt

Run the initial-deploy.sh script to bootstrap the development and production environments and to deploy the default pipeline. You’ll be asked to provide the following parameters: (1) Development account ID, (2) Development account AWS profile name, (3) Production account ID, and (4) Production account AWS profile name.

sh ./initial-deploy.sh –dev_account_id <YOUR DEV ACCOUNT ID> —
dev_profile_name <YOUR DEV PROFILE NAME> –prod_account_id <YOUR PRODUCTION
ACCOUNT ID> –prod_profile_name <YOUR PRODUCTION PROFILE NAME>

Default pipeline

In the CI/CD pipeline, we set up an if condition to deploy the default branch resources only if the current branch is the default one. The default branch is retrieved programmatically from the CodeCommit repository. We deploy an Amazon Simple Storage Service (Amazon S3) Bucket and two Lambda functions. The bucket is responsible for storing the feature branches’ CodeBuild artifacts. The first Lambda function is triggered when a new branch is created in CodeCommit. The second one is triggered when a branch is deleted.

if branch == default_branch:

…

# Artifact bucket for feature AWS CodeBuild projects
artifact_bucket = Bucket(
self,
‘BranchArtifacts’,
encryption=BucketEncryption.KMS_MANAGED,
removal_policy=RemovalPolicy.DESTROY,
auto_delete_objects=True
)
…
# AWS Lambda function triggered upon branch creation
create_branch_func = aws_lambda.Function(
self,
‘LambdaTriggerCreateBranch’,
runtime=aws_lambda.Runtime.PYTHON_3_8,
function_name=’LambdaTriggerCreateBranch’,
handler=’create_branch.handler’,
code=aws_lambda.Code.from_asset(path.join(this_dir, ‘code’)),
environment={
“ACCOUNT_ID”: dev_account_id,
“CODE_BUILD_ROLE_ARN”: iam_stack.code_build_role.role_arn,
“ARTIFACT_BUCKET”: artifact_bucket.bucket_name,
“CODEBUILD_NAME_PREFIX”: codebuild_prefix
},
role=iam_stack.create_branch_role)

# AWS Lambda function triggered upon branch deletion
destroy_branch_func = aws_lambda.Function(
self,
‘LambdaTriggerDestroyBranch’,
runtime=aws_lambda.Runtime.PYTHON_3_8,
function_name=’LambdaTriggerDestroyBranch’,
handler=’destroy_branch.handler’,
role=iam_stack.delete_branch_role,
environment={
“ACCOUNT_ID”: dev_account_id,
“CODE_BUILD_ROLE_ARN”: iam_stack.code_build_role.role_arn,
“ARTIFACT_BUCKET”: artifact_bucket.bucket_name,
“CODEBUILD_NAME_PREFIX”: codebuild_prefix,
“DEV_STAGE_NAME”: f'{dev_stage_name}-{dev_stage.main_stack_name}’
},
code=aws_lambda.Code.from_asset(path.join(this_dir,
‘code’)))

Then, the CodeCommit repository is configured to trigger these Lambda functions based on two events:

(1) Reference created

# Configure AWS CodeCommit to trigger the Lambda function when a new branch is created
repo.on_reference_created(
‘BranchCreateTrigger’,
description=”AWS CodeCommit reference created event.”,
target=aws_events_targets.LambdaFunction(create_branch_func))

(2) Reference deleted

# Configure AWS CodeCommit to trigger the Lambda function when a branch is deleted
repo.on_reference_deleted(
‘BranchDeleteTrigger’,
description=”AWS CodeCommit reference deleted event.”,
target=aws_events_targets.LambdaFunction(destroy_branch_func))

Lambda functions

The two Lambda functions build and destroy application environments mapped to each feature branch. An Amazon CloudWatch event triggers the LambdaTriggerCreateBranch function whenever a new branch is created. The CodeBuild client from boto3 creates the build phase and deploys the feature pipeline.

Create function

The create function deploys a feature pipeline which consists of a build stage and an optional update pipeline stage for itself. The pipeline downloads the feature branch code from the CodeCommit repository, initiates the Build and Test action using CodeBuild, and securely saves the built artifact on the S3 bucket.

The Lambda function handler code is as follows:

def handler(event, context):
“””Lambda function handler”””
logger.info(event)

reference_type = event[‘detail’][‘referenceType’]

try:
if reference_type == ‘branch’:
branch = event[‘detail’][‘referenceName’]
repo_name = event[‘detail’][‘repositoryName’]

client.create_project(
name=f'{codebuild_name_prefix}-{branch}-create’,
description=”Build project to deploy branch pipeline”,
source={
‘type’: ‘CODECOMMIT’,
‘location’: f’https://git-codecommit.{region}.amazonaws.com/v1/repos/{repo_name}’,
‘buildspec’: generate_build_spec(branch)
},
sourceVersion=f’refs/heads/{branch}’,
artifacts={
‘type’: ‘S3’,
‘location’: artifact_bucket_name,
‘path’: f'{branch}’,
‘packaging’: ‘NONE’,
‘artifactIdentifier’: ‘BranchBuildArtifact’
},
environment={
‘type’: ‘LINUX_CONTAINER’,
‘image’: ‘aws/codebuild/standard:4.0’,
‘computeType’: ‘BUILD_GENERAL1_SMALL’
},
serviceRole=role_arn
)

client.start_build(
projectName=f’CodeBuild-{branch}-create’
)
except Exception as e:
logger.error(e)

Create branch CodeBuild project’s buildspec.yaml content:

version: 0.2
env:
variables:
BRANCH: {branch}
DEV_ACCOUNT_ID: {account_id}
PROD_ACCOUNT_ID: {account_id}
REGION: {region}
phases:
pre_build:
commands:
– npm install -g aws-cdk && pip install -r requirements.txt
build:
commands:
– cdk synth
– cdk deploy –require-approval=never
artifacts:
files:
– ‘**/*’

Destroy function

The second Lambda function is responsible for the destruction of a feature branch’s resources. Upon the deletion of a feature branch, an Amazon CloudWatch event triggers this Lambda function. The function creates a CodeBuild Project which destroys the feature pipeline and all of the associated resources created by that pipeline. The source property of the CodeBuild Project is the feature branch’s source code saved as an artifact in Amazon S3.

The Lambda function handler code is as follows:

def handler(event, context):
logger.info(event)
reference_type = event[‘detail’][‘referenceType’]

try:
if reference_type == ‘branch’:
branch = event[‘detail’][‘referenceName’]
client.create_project(
name=f'{codebuild_name_prefix}-{branch}-destroy’,
description=”Build project to destroy branch resources”,
source={
‘type’: ‘S3’,
‘location’: f'{artifact_bucket_name}/{branch}/CodeBuild-{branch}-create/’,
‘buildspec’: generate_build_spec(branch)
},
artifacts={
‘type’: ‘NO_ARTIFACTS’
},
environment={
‘type’: ‘LINUX_CONTAINER’,
‘image’: ‘aws/codebuild/standard:4.0’,
‘computeType’: ‘BUILD_GENERAL1_SMALL’
},
serviceRole=role_arn
)

client.start_build(
projectName=f’CodeBuild-{branch}-destroy’
)

client.delete_project(
name=f’CodeBuild-{branch}-destroy’
)

client.delete_project(
name=f’CodeBuild-{branch}-create’
)
except Exception as e:
logger.error(e)

Destroy the branch CodeBuild project’s buildspec.yaml content:

version: 0.2
env:
variables:
BRANCH: {branch}
DEV_ACCOUNT_ID: {account_id}
PROD_ACCOUNT_ID: {account_id}
REGION: {region}
phases:
pre_build:
commands:
– npm install -g aws-cdk && pip install -r requirements.txt
build:
commands:
– cdk destroy cdk-pipelines-multi-branch-{branch} –force
– aws cloudformation delete-stack –stack-name {dev_stage_name}-{branch}
– aws s3 rm s3://{artifact_bucket_name}/{branch} –recursive

Create a feature branch

On your machine’s local copy of the repository, create a new feature branch using the following git commands. Replace user-feature-123 with a unique name for your feature branch. Note that this feature branch name must comply with the CodePipeline naming restrictions, as it will be used to name a unique pipeline later in this walkthrough.

# Create the feature branch
git checkout -b user-feature-123
git push origin user-feature-123

The first Lambda function will deploy the CodeBuild project, which then deploys the feature pipeline. This can take a few minutes. You can log in to the AWS Console and see the CodeBuild project running under CodeBuild.

Figure 2. AWS Console – CodeBuild projects.

After the build is successfully finished, you can see the deployed feature pipeline under CodePipelines.

Figure 3. AWS Console – CodePipeline pipelines.

The Lambda S3 trigger project from AWS CDK Samples is used as the infrastructure resources to demonstrate this solution. The content is placed inside the src directory and is deployed by the pipeline. When visiting the Lambda console page, you can see two functions: one by the default pipeline and one by our feature pipeline.

Figure 4. AWS Console – Lambda functions.

Destroy a feature branch

There are two common ways for removing feature branches. The first one is related to a pull request, also known as a “PR”. This occurs when merging a feature branch back into the default branch. Once it’s merged, the feature branch will be automatically closed. The second way is to delete the feature branch explicitly by running the following git commands:

# delete branch local
git branch -d user-feature-123

# delete branch remote
git push origin –delete user-feature-123

The CodeBuild project responsible for destroying the feature resources is now triggered. You can see the project’s logs while the resources are being destroyed in CodeBuild, under Build history.

Figure 5. AWS Console – CodeBuild projects.

Cleaning up

To avoid incurring future charges, log into the AWS console of the different accounts you used, go to the AWS CloudFormation console of the Region(s) where you chose to deploy, and select and click Delete on the main and branch stacks.

Conclusion

This post showed how you can work with an event-driven strategy and AWS CDK to implement a multi-branch pipeline flow using AWS CDK Pipelines. The described solutions leverage Lambda and CodeBuild to provide a dynamic orchestration of resources for multiple branches and pipelines.
For more information on CDK Pipelines and all the ways it can be used, see the CDK Pipelines reference documentation.

About the authors:

Iris Kraja

Iris is a Cloud Application Architect at AWS Professional Services based in New York City. She is passionate about helping customers design and build modern AWS cloud native solutions, with a keen interest in serverless technology, event-driven architectures and DevOps. Outside of work, she enjoys hiking and spending as much time as possible in nature.

Jan Bauer

Jan is a Cloud Application Architect at AWS Professional Services. His interests are serverless computing, machine learning, and everything that involves cloud computing.

Rolando Santamaria Maso

Rolando is a senior cloud application development consultant at AWS Professional Services, based in Germany. He helps customers migrate and modernize workloads in the AWS Cloud, with a special focus on modern application architectures and development best practices, but he also creates IaC using AWS CDK. Outside work, he maintains open-source projects and enjoys spending time with family and friends.

Caroline Gluck

Caroline is an AWS Cloud application architect based in New York City, where she helps customers design and build cloud native data science applications. Caroline is a builder at heart, with a passion for serverless architecture and machine learning. In her spare time, she enjoys traveling, cooking, and spending time with family and friends.

Implementing an API Gateway in ASP.NET Core with Ocelot

Posted on February 23, 2022May 21, 2023 by Mark Feehily0

This post is about what is an API Gateway and how to build an API Gateway in ASP.NET Core with Ocelot. An API gateway is service that sits between an endpoint and backend APIs, transmitting client requests to an appropriate service of an application. It’s an architectural pattern, which was initially created to support microservices. In this post I am building API Gateway using Ocelot. Ocelot is aimed at people using .NET running a micro services / service orientated architecture that need a unified point of entry into their system.

Let’s start the implementation.

First we will create two web api applications – both these services returns some hard coded string values. Here is the first web api – CustomersController – which returns list of customers.

using Microsoft.AspNetCore.Mvc;

namespace ServiceA.Controllers;

[ApiController]
[Route(“[controller]”)]
public class CustomersController : ControllerBase
{
private readonly ILogger<CustomersController> _logger;

public CustomersController(ILogger<CustomersController> logger)
{
_logger = logger;
}

[HttpGet(Name = “GetCustomers”)]
public IActionResult Get()
{
return Ok(new[] { “Customer1”, “Customer2”,“Customer3” });
}
}

And here is the second web api – ProductsController.

using Microsoft.AspNetCore.Mvc;

namespace ServiceB.Controllers;

[ApiController]
[Route(“[controller]”)]
public class ProductsController : ControllerBase
{
private readonly ILogger<ProductsController> _logger;

public ProductsController(ILogger<ProductsController> logger)
{
_logger = logger;
}

[HttpGet(Name = “GetProducts”)]
public IActionResult Get()
{
return Ok(new[] { “Product1”, “Product2”,
“Product3”, “Product4”, “Product5” });
}
}

Next we will create the API Gateway. To do this create an ASP.NET Core empty web application using the command – dotnet new web -o ApiGateway. Once we create the gateway application, we need to add the reference of Ocelot nuget package – we can do this using dotnet add package Ocelot. Now we can modify the Program.cs file like this.

using Ocelot.DependencyInjection;
using Ocelot.Middleware;

var builder = WebApplication.CreateBuilder(args);

builder.Configuration.SetBasePath(Directory.GetCurrentDirectory())
.AddJsonFile(“configuration.json”, false, true).AddEnvironmentVariables();

builder.Services.AddOcelot(builder.Configuration);
var app = builder.Build();

app.UseOcelot();
app.Run();

Next you need to configure your API routes using configuration.json. Here is the basic configuration which help to send requests from one endpoint to the web api endpoints.

{
“Routes“: [
{
“DownstreamPathTemplate“: “/customers“,
“DownstreamScheme“: “https“,
“DownstreamHostAndPorts“: [
{
“Host“: “localhost“,
“Port“: 7155
}
],
“UpstreamPathTemplate“: “/api/customers“,
“UpstreamHttpMethod“: [ “Get“ ]
},
{
“DownstreamPathTemplate“: “/products“,
“DownstreamScheme“: “https“,
“DownstreamHostAndPorts“: [
{
“Host“: “localhost“,
“Port“: 7295
}
],
“UpstreamPathTemplate“: “/api/products“,
“UpstreamHttpMethod“: [ “Get“ ]
}
],
“GlobalConfiguration“: {
“BaseUrl“: “https://localhost:7043“
}
}

Now run all the three applications and browse the endpoint – https://localhost:7043/api/products – which invokes the ProductsController class GET action method. And if we browse the endpoint – https://localhost:7043/api/customers – which invokes the CustomersController GET action method. In the configuration the UpstreamPathTemplate will be the API Gateway endpoint and API Gateway will transfers the request to the DownstreamPathTemplate endpoint.

Due to some strange reason it was not working properly for me. Today I configured it again and it started working. It is an introductory post. I will blog about some common use cases where API Gateway help and how to deploy it in Azure and all in the future.

Happy Programming 🙂