カテゴリー: tech

Introduction

In the fast-evolving landscape of cloud infrastructure, keeping our Infrastructure as Code (IaC) up to date is crucial for maintaining efficiency, security, and cost-effectiveness. Recently, I encountered a scenario where a type I commonly used in AWS Cloud Development Kit (CDK) was marked as deprecated, leading to confusion due to the lack of updated documentation. This blog post aims to share my journey of identifying the issue, understanding the implications, and finding a workaround.

The Challenge: Unexpected Deprecation

While defining a Virtual Private Cloud (VPC) using AWS CDK in TypeScript, I noticed that the SubnetType.PRIVATE_WITH_NAT was unexpectedly marked as “deprecated.” Here’s a snippet of the code that led to the discovery:

import { Vpc, SubnetType } from '@aws-cdk/aws-ec2';

const vpc = new Vpc(this, "Vpc", {
  subnetConfiguration: [
    { name: "Public", subnetType: SubnetType.PUBLIC },
    { name: "Private", subnetType: SubnetType.PRIVATE_WITH_NAT },
    { name: "Isolated", subnetType: SubnetType.PRIVATE_ISOLATED }
  ]
});

Despite this, the official documentation had no mention of the deprecation, leaving me in a state of confusion about the correct approach to defining private subnets with NAT.

Investigating the Issue

To understand why PRIVATE_WITH_NAT was marked as deprecated and to find a solution, I embarked on a deep dive into the CDK source code, issue trackers, and the AWS documentation for updates. My setup involved using CDK CLI version 2.60 on MacOS 12.5, with Node.js version 14.17 and TypeScript version 4.9.4.

Solution: Adapting to the Changes

After thorough research, I learned that AWS CDK evolves rapidly, and certain types or methods can become deprecated as part of this evolution. The deprecation of PRIVATE_WITH_NAT was a move towards a more granular and flexible way of defining subnet configurations, allowing for better control over the networking architecture in AWS.

Updated Approach

To adapt to the change, I revised my VPC definition to use the updated subnet types and configurations, ensuring that my infrastructure code remained functional and aligned with the best practices. Here’s an updated snippet reflecting the changes:

import { Vpc, SubnetType } from '@aws-cdk/aws-ec2';

const vpc = new Vpc(this, "Vpc", {
  subnetConfiguration: [
    { name: "Public", subnetType: SubnetType.PUBLIC },
    // Adjusted to use the new method or type for private subnets with NAT
    { name: "Private", subnetType: SubnetType.PRIVATE },
    { name: "Isolated", subnetType: SubnetType.PRIVATE_ISOLATED }
  ]
});

Note: This snippet assumes a generic update and might need adjustment based on the specific alternatives provided by AWS CDK at the time of your implementation.

Conclusion

Dealing with deprecations in IaC can be challenging, especially when documentation does not immediately reflect these changes. However, it also presents an opportunity to dive deeper into the tools we use, understanding their internals and staying ahead of the curve. Through this experience, I’ve learned the importance of regularly reviewing the release notes of the tools and libraries in our stack, participating in community forums, and testing our infrastructure regularly to catch such issues early.

I hope this case study helps other developers navigate similar challenges and encourages an active engagement with the evolving cloud ecosystem.

この記事を読んで学べること:

• 「oblivious」という言葉の意味と会話での使用法
• 相手が注意を払っていない時の優しい指摘の仕方
• 英語での間接的な表現を用いたフィードバックの技術

今回の表現: “You’re an oblivious one, aren’t you? Well, never mind then.”

日本語訳: 「あなたは気づかないタイプですね。まあ、いいですけど。」

文法解析: このフレーズは、「oblivious」を用いて相手が何かに気づいていないことを指摘し、「aren’t you?」でその事実を相手に問いかけます。続く「Well, never mind then.」は、その状況を受け入れ、話を進める意思を示しています。

他の表現との違い:

覚えておくべきポイント: 「You’re an oblivious one, aren’t you?」という表現は、相手が何かを見落としていることを指摘する際に使われることがありますが、この言い方は非常にカジュアルで、親しい間柄でなければ不快に感じられる可能性があります。会話においては、このような表現を使う前に、相手との関係性や文脈を考慮することが重要です。

はじめに

AWS Lambdaは、サーバーレスコンピューティングを可能にするAWSの重要なサービスですが、Lambda はGo1.xランタイムの廃止とprovided.al2ランタイムへの移行を予定しています​​。

この記事では実際に変更した際に修正した箇所についてまとめます。

変更内容

公式ブログと、クラメソさんの記事を参考に以下の通り変更しました

Resources:
  HelloWorldFunction:
    Type: AWS::Serverless::Function
    Metadata:
      BuildMethod: go1.x 
    Properties:
      CodeUri: hello-world/ # folder where your main program resides
      Handler: bootstrap
      Runtime: provided.al2
      Architectures:
        - x86_64

sam deploy 後

以下のようなエラーが発生しました

Phase: invoke Status: error Error Type: Runtime.Unknown

問題への対処

調べたところ、 github.com/aws/aws-lambda-goが古いとal2 runtimeに対応してないことがわかりました。 そのため、以下の対処を行いました。

go get github.com/aws/aws-lambda-go
go mod download gopkg.in/yaml.v3 

古い aws-lambda-go は provided.ai2 ランタイムには対応してないようで細心にする必要があったようです。