Extremely Popular
123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244// Copyright 2018-2020 the oak authors. All rights reserved. MIT license.
import { contentType, Status } from "./deps.ts";import { Request } from "./request.ts";import { isHtml, isRedirectStatus, encodeUrl } from "./util.ts";
type Body = | string | number | bigint | boolean | symbol | object | undefined | null;type BodyFunction = () => Body | Promise<Body>;
interface ServerResponse { status: number; headers: Headers; body: Uint8Array | Deno.Reader | undefined;}
export const REDIRECT_BACK = Symbol("redirect backwards");
const BODY_TYPES = ["string", "number", "bigint", "boolean", "symbol"];
const encoder = new TextEncoder();
/** Guard for `Deno.Reader`. */function isReader(value: any): value is Deno.Reader { return typeof value === "object" && "read" in value && typeof value.read === "function";}
function isPromiseLike(value: any): value is PromiseLike<any> { return value && typeof value === "object" && "then" in value && typeof value.then === "function";}
async function convertBody( body: Body | BodyFunction, type?: string,): Promise<[Uint8Array | Deno.Reader | undefined, string | undefined]> { let result: Uint8Array | Deno.Reader | undefined; if (BODY_TYPES.includes(typeof body)) { const bodyText = String(body); result = encoder.encode(bodyText); type = type ?? (isHtml(bodyText) ? "html" : "text/plain"); } else if (body instanceof Uint8Array || isReader(body)) { result = body; } else if (body && typeof body === "object") { result = encoder.encode(JSON.stringify(body)); type = type ?? "json"; } else if (typeof body === "function") { const result = body.call(null); return convertBody(isPromiseLike(result) ? await result : result, type); } else if (body) { throw new TypeError("Response body was set but could not convert."); } return [result, type];}
export class Response { #body?: Body | BodyFunction; #headers = new Headers(); #request: Request; #serverResponse?: ServerResponse; #status?: Status; #type?: string; #writable = true;
#getBody = async (): Promise<Uint8Array | Deno.Reader | undefined> => { const [body, type] = await convertBody(this.body, this.type); this.type = type; return body; };
#setContentType = (): void => { if (this.type) { const contentTypeString = contentType(this.type); if (contentTypeString && !this.headers.has("Content-Type")) { this.headers.append("Content-Type", contentTypeString); } } };
/** The body of the response. The body will be automatically processed when * the response is being sent and converted to a `Uint8Array` or a * `Deno.Reader`. */ get body(): Body | BodyFunction { return this.#body; }
/** The body of the response. The body will be automatically processed when * the response is being sent and converted to a `Uint8Array` or a * `Deno.Reader`. */ set body(value: Body | BodyFunction) { if (!this.#writable) { throw new Error("The response is not writable."); } this.#body = value; }
/** Headers that will be returned in the response. */ get headers(): Headers { return this.#headers; }
/** Headers that will be returned in the response. */ set headers(value: Headers) { if (!this.#writable) { throw new Error("The response is not writable."); } this.#headers = value; }
/** The HTTP status of the response. If this has not been explicitly set, * reading the value will return what would be the value of status if the * response were sent at this point in processing the middleware. If the body * has been set, the status will be `200 OK`. If a value for the body has * not been set yet, the status will be `404 Not Found`. */ get status(): Status { if (this.#status) { return this.#status; } const typeofbody = typeof this.body; return this.body && (BODY_TYPES.includes(typeofbody) || typeofbody === "object") ? Status.OK : Status.NotFound; }
/** The HTTP status of the response. If this has not been explicitly set, * reading the value will return what would be the value of status if the * response were sent at this point in processing the middleware. If the body * has been set, the status will be `200 OK`. If a value for the body has * not been set yet, the status will be `404 Not Found`. */ set status(value: Status) { if (!this.#writable) { throw new Error("The response is not writable."); } this.#status = value; }
/** The media type, or extension of the response. Setting this value will * ensure an appropriate `Content-Type` header is added to the response. */ get type(): string | undefined { return this.#type; } set type(value: string | undefined) { if (!this.#writable) { throw new Error("The response is not writable."); } this.#type = value; }
/** A read-only property which determines if the response is writable or not. * Once the response has been processed, this value is set to `false`. */ get writable(): boolean { return this.#writable; }
constructor(request: Request) { this.#request = request; }
/** Sets the response to redirect to the supplied `url`. * * If the `.status` is not currently a redirect status, the status will be set * to `302 Found`. * * The body will be set to a message indicating the redirection is occurring. */ redirect(url: string | URL): void; /** Sets the response to redirect back to the referrer if available, with an * optional `alt` URL if there is no referrer header on the request. If there * is no referrer header, nor an `alt` parameter, the redirect is set to `/`. * * If the `.status` is not currently a redirect status, the status will be set * to `302 Found`. * * The body will be set to a message indicating the redirection is occurring. */ redirect(url: typeof REDIRECT_BACK, alt?: string | URL): void; redirect( url: string | URL | typeof REDIRECT_BACK, alt: string | URL = "/", ): void { if (url === REDIRECT_BACK) { url = this.#request.headers.get("Referrer") ?? String(alt); } else if (typeof url === "object") { url = String(url); } this.headers.set("Location", encodeUrl(url)); if (!this.status || !isRedirectStatus(this.status)) { this.status = Status.Found; }
if (this.#request.accepts("html")) { url = encodeURI(url); this.type = "text/html; charset=utf-8"; this.body = `Redirecting to <a href="${url}">${url}</a>.`; return; } this.type = "text/plain; charset=utf-8"; this.body = `Redirecting to ${url}.`; }
/** Take this response and convert it to the response used by the Deno net * server. Calling this will set the response to not be writable. */ async toServerResponse(): Promise<ServerResponse> { if (this.#serverResponse) { return this.#serverResponse; } // Process the body const body = await this.#getBody();
// If there is a response type, set the content type header this.#setContentType();
const { headers } = this;
// If there is no body and no content type and no set length, then set the // content length to 0 if ( !( body || headers.has("Content-Type") || headers.has("Content-Length") ) ) { headers.append("Content-Length", "0"); }
this.#writable = false; return this.#serverResponse = { status: this.#status ?? (body ? Status.OK : Status.NotFound), body, headers, }; }}