Luke
☁️ Cloud Native 🌈 DevOps ⚡️ Serverless ⌨️ Node.js
Luke Hedger
The LEGO Group and AWS Community Builder
Serverless Days: Student Edition - Aug 2022
AWS Lambda
- Serverless compute requires a novel approach and mindset
- But... the basics of Lambda will still allow to gain benefits (cost, scale etc)
- Reach for the advanced features as complexity grows
Lifecycle
- Compute model → programming model
- Init phase runs "code outside handler"
- Invocation phase runs "code inside handler"
Concurrency Model
Lambda's unit of scale is concurrency
Work With Constraints
-
Maximum concurrent executions = 1,000
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Maximum function duration = 15 minutes
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Maximum memory allocation = 10,240 MB
Optimise with Lambda Insights
Runtime & Language
- Choose runtime/language to suit use case and team
- Use latest Node.js version when possible
- Use arm64 architecture (AWS Graviton2)
Files and Folders
- Prefer a single file per function over early abstractions
- If the file/function grows substantially consider architecture
- Use a directory structure that works for you and change if needed
Code Standards
- Use Prettier's default rules
- Keep ESLint rules to a minimum. Use someone else’s rules with caution
- Keep config in root, not tied to specific functions or services
TypeScript
AWS SDK
Testing
Security
- Keep dependencies updated, especially vulnerability patches
- Apply the Principle of Least Privilege to IAM policies - i.e. do not use * (wildcards)!
- Use the OWASP Serverless Top 10 to mitigate common serverless application security vulnerabilities
Observability
- Monitor metrics for Concurrent Executions, Throttles and Errors
- Route alarms to team chat
- Use dashboards to view critical health
Powertools
- Lambda Powertools for TypeScript
- Logs, metrics and tracing
Resources
Thanks!
How to write Node.js Lambda functions
By Luke
How to write Node.js Lambda functions
In this talk, Luke will walk-through how to write the most awesome Node.js Lambda functions, from project initialization through to operation. We'll look at how AWS Lambda functions work and why this matters. We'll then explore the best practice for folder structure, code standards, static analysis, testing, security and monitoring. All by employing the latest and greatest standards, as used by serverless experts!
