response.ts

import type {Buffer} from 'node:buffer';
import type {IncomingMessageWithTimings, Timings} from '@szmarczak/http-timer';
import {RequestError} from './errors.js';
import type {ParseJsonFunction, ResponseType} from './options.js';
import type Request from './index.js';

export type PlainResponse = {
	/**
	The original request URL.
	*/
	requestUrl: URL;

	/**
	The redirect URLs.
	*/
	redirectUrls: URL[];

	/**
	- `options` - The Got options that were set on this request.

	__Note__: This is not a [http.ClientRequest](https://nodejs.org/api/http.html#http_class_http_clientrequest).
	*/
	request: Request;

	/**
	The remote IP address.

	This is hopefully a temporary limitation, see [lukechilds/cacheable-request#86](https://github.com/lukechilds/cacheable-request/issues/86).

	__Note__: Not available when the response is cached.
	*/
	ip?: string;

	/**
	Whether the response was retrieved from the cache.
	*/
	isFromCache: boolean;

	/**
	The status code of the response.
	*/
	statusCode: number;

	/**
	The request URL or the final URL after redirects.
	*/
	url: string;

	/**
	The object contains the following properties:

	- `start` - Time when the request started.
	- `socket` - Time when a socket was assigned to the request.
	- `lookup` - Time when the DNS lookup finished.
	- `connect` - Time when the socket successfully connected.
	- `secureConnect` - Time when the socket securely connected.
	- `upload` - Time when the request finished uploading.
	- `response` - Time when the request fired `response` event.
	- `end` - Time when the response fired `end` event.
	- `error` - Time when the request fired `error` event.
	- `abort` - Time when the request fired `abort` event.
	- `phases`
		- `wait` - `timings.socket - timings.start`
		- `dns` - `timings.lookup - timings.socket`
		- `tcp` - `timings.connect - timings.lookup`
		- `tls` - `timings.secureConnect - timings.connect`
		- `request` - `timings.upload - (timings.secureConnect || timings.connect)`
		- `firstByte` - `timings.response - timings.upload`
		- `download` - `timings.end - timings.response`
		- `total` - `(timings.end || timings.error || timings.abort) - timings.start`

	If something has not been measured yet, it will be `undefined`.

	__Note__: The time is a `number` representing the milliseconds elapsed since the UNIX epoch.
	*/
	timings: Timings;

	/**
	The number of times the request was retried.
	*/
	retryCount: number;

	// Defined only if request errored
	/**
	The raw result of the request.
	*/
	rawBody?: Buffer;

	/**
	The result of the request.
	*/
	body?: unknown;

	/**
	Whether the response was successful.

	__Note__: Got throws automatically when `response.ok` is `false` and `throwHttpErrors` is `true`.
	*/
	ok: boolean;
} & IncomingMessageWithTimings;

// For Promise support
export type Response<T = unknown> = {
	/**
	The result of the request.
	*/
	body: T;

	/**
	The raw result of the request.
	*/
	rawBody: Buffer;
} & PlainResponse;

export const isResponseOk = (response: PlainResponse): boolean => {
	const {statusCode} = response;
	const {followRedirect} = response.request.options;
	const shouldFollow = typeof followRedirect === 'function' ? followRedirect(response) : followRedirect;
	const limitStatusCode = shouldFollow ? 299 : 399;

	return (statusCode >= 200 && statusCode <= limitStatusCode) || statusCode === 304;
};

/**
An error to be thrown when server response code is 2xx, and parsing body fails.
Includes a `response` property.
*/
export class ParseError extends RequestError {
	declare readonly response: Response;

	constructor(error: Error, response: Response) {
		const {options} = response.request;

		super(`${error.message} in "${options.url!.toString()}"`, error, response.request);
		this.name = 'ParseError';
		this.code = 'ERR_BODY_PARSE_FAILURE';
	}
}

export const parseBody = (response: Response, responseType: ResponseType, parseJson: ParseJsonFunction, encoding?: BufferEncoding): unknown => {
	const {rawBody} = response;

	try {
		if (responseType === 'text') {
			return rawBody.toString(encoding);
		}

		if (responseType === 'json') {
			return rawBody.length === 0 ? '' : parseJson(rawBody.toString(encoding));
		}

		if (responseType === 'buffer') {
			return rawBody;
		}
	} catch (error) {
		throw new ParseError(error as Error, response);
	}

	throw new ParseError({
		message: `Unknown body type '${responseType as string}'`,
		name: 'Error',
	}, response);
};