# ClientContextEnv

**Kind:** Interface

**Source:** [`src/adapter/aws-lambda/types.ts`](https://github.com/honojs/hono/blob/main/src/adapter/aws-lambda/types.ts#L23)

**Part of:** [Adapter](subsystem-src-adapter)

`ClientContextEnv` describes device and platform details from an AWS Lambda client context. It stores the platform version, platform name, device make and model, and locale for request-aware processing.

## Properties

| Property | Type |
|---|---|
| `platformVersion` | `string` |
| `platform` | `string` |
| `make` | `string` |
| `model` | `string` |
| `locale` | `string` |

## Diagram

```mermaid
graph LR
  ClientContextEnv --> platformVersion
  ClientContextEnv --> platform
  ClientContextEnv --> make
  ClientContextEnv --> model
  ClientContextEnv --> locale
```

## Usage

```ts
import type { ClientContextEnv } from './types';

const environment: ClientContextEnv = {
  platformVersion: '17.0',
  platform: 'iOS',
  make: 'Apple',
  model: 'iPhone',
  locale: 'en-US',
};

function getDeviceLabel(env: ClientContextEnv): string {
  return `${env.make} ${env.model} (${env.platform} ${env.platformVersion})`;
}

console.log(getDeviceLabel(environment));
```

## AI Coding Instructions

- Keep all `ClientContextEnv` fields as strings when mapping AWS Lambda client context data.
- Handle missing client context before creating a `ClientContextEnv` object.
- Preserve the source locale value rather than converting it during request parsing.
- Use this interface for device and platform metadata passed between the AWS Lambda adapter and request handling code.

## How it works

`ClientContextEnv` is an exported TypeScript interface that declares the environment portion of a Lambda client context. It contains five required `string` fields: `platformVersion`, `platform`, `make`, `model`, and `locale`. [src/adapter/aws-lambda/types.ts:23-29]

It is the type of the required `env` property on `ClientContext`. [src/adapter/aws-lambda/types.ts:8-13] A `ClientContext` can appear as the optional `clientContext` property of `LambdaContext`, which is passed to handlers as their `context` argument. [src/adapter/aws-lambda/types.ts:35-56]

The interface declares no methods, runtime validation, error handling, or side effects. [src/adapter/aws-lambda/types.ts:23-29]