LatticeV2Processor

Kind: Class

Source: src/adapter/aws-lambda/handler.ts

Part of: Adapter

LatticeV2Processor adapts an AWS VPC Lattice event into request data consumed by the Lambda handler. It reads the request path, method, query string, headers, and cookies, then writes response cookies back to the Lambda result.

Extends: EventProcessor

Methods

Diagram

mermaid
graph LR
  Event[AWS VPC Lattice event] --> Processor[LatticeV2Processor]
  Processor --> Path[getPath()]
  Processor --> Method[getMethod()]
  Processor --> Query[getQueryString()]
  Processor --> Headers[getHeaders()]
  Processor --> Cookies[getCookies()]
  Processor --> Result[Lambda response]
  Cookies --> SetCookies[setCookiesToResult()]
  SetCookies --> Result

Usage

ts
import { LatticeV2Processor } from './handler'

function inspectRequest(processor: LatticeV2Processor) {
  const path = processor.getPath()
  const method = processor.getMethod()
  const queryString = processor.getQueryString()
  const headers = processor.getHeaders()

  processor.getCookies()

  console.log({
    path,
    method,
    queryString,
    contentType: headers.get('content-type'),
  })

  processor.setCookiesToResult()
}

AI Coding Instructions

• Keep request access behind LatticeV2Processor methods instead of reading the VPC Lattice event directly in handler logic.
• Treat getHeaders() as the source for request header lookups and use the Headers API for case-insensitive access.
• Call getCookies() before code that depends on request cookies.
• Call setCookiesToResult() after response cookies are prepared so they are included in the Lambda result.
• Keep VPC Lattice-specific event handling in src/adapter/aws-lambda/handler.ts.

How it works

LatticeV2Processor is the exported EventProcessor<LatticeProxyEventV2> specialization for Lambda events whose request context has a serviceArn property. getProcessor() selects its shared instance after excluding ALB and API Gateway v2 event shapes. src/adapter/aws-lambda/handler.ts:584-623 src/adapter/aws-lambda/handler.ts:625-657

Its event type requires a path, HTTP method, array-valued headers and query-string parameters, nullable body, base64 flag, and a Lattice v2 request context. That context includes serviceArn, serviceNetworkArn, targetGroupArn, region, timestamp, and identity fields. src/adapter/aws-lambda/handler.ts:29-38 src/adapter/aws-lambda/types.ts:155-173