Http

A collection of functions to work with http.

cacheHeaders

Generates a cache-control header object from the provided options.

If enabled: false, the cache-control header will be 'private, no-cache, noindex, max-age=0, must-revalidate'.

type CacheHeadersOptions = {
	// Disables the cache entirely
	enabled?: boolean;
	// All cache-control directives
	maxAge?: number;
	sMaxAge?: number;
	staleWhileRevalidate?: number;
	staleIfError?: number;
	private?: boolean;
	public?: boolean;
	noCache?: boolean;
	noStore?: boolean;
	noTransform?: boolean;
	immutable?: boolean;
	mustRevalidate?: boolean;
	proxyRevalidate?: boolean;
	mustUnderstand?: boolean;
};

const cacheControl = cacheHeaders({
	// ...
});

return new Response('', {
	headers: cacheControl
});

fetchTimeout

Fetch with a timeout. Defaults to 20 seconds.

// 5 second timeout
const response = await fetchTimeout(url, { ... }, 5000);

isRedirectResponse

Returns true if the response is a redirect response.

const isRedirectResponse: (response: Response) => boolean;

isWithoutBody

Returns true if the request should not have a body.

const isWithoutBody: (request: Request) => boolean;

getLangFromRequest (deprecated)

Get the language from the request.

const getLangFromRequest = <Language extends string>(
	request: Request,
	{ supportedLanguages: Language[]; defaultLanguage: Language }
) => Language;

parseAcceptLanguage

Given a string of the form "en,fr;q=0.9,de;q=0.8", returns an array of AcceptLanguageEntry ordered by priority. This is mostly used to parse the 'Accept-Language' header.

type AcceptLanguageEntry = {
	lang: string;
	priority: number;
};

const parseAcceptLanguage = (acceptLanguage: string): Maybe<AcceptLanguageEntry[]>

acceptedLanguage

Get the accepted language from the request.

const language = acceptedLanguage(request, {
	supportedLanguages: ['en', 'fr'],
	defaultLanguage: 'en'
});

getVercelIpHeaders

Get Vercel headers from a request.

const getVercelIpHeaders: (request: Request) => {
	country: Maybe<string>;
	region: Maybe<string>;
	city: Maybe<string>;
	latitude: Maybe<string>;
	longitude: Maybe<string>;
	timezone: Maybe<string>;
	ip: Maybe<string>;
};