852 lines
28 KiB
JavaScript
852 lines
28 KiB
JavaScript
/**
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* Fetching content from the web is environment-specific, so Ethers
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* provides an abstraction that each environment can implement to provide
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* this service.
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*
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* On [Node.js](link-node), the ``http`` and ``https`` libs are used to
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* create a request object, register event listeners and process data
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* and populate the [[FetchResponse]].
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*
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* In a browser, the [DOM fetch](link-js-fetch) is used, and the resulting
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* ``Promise`` is waited on to retrieve the payload.
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*
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* The [[FetchRequest]] is responsible for handling many common situations,
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* such as redirects, server throttling, authentication, etc.
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*
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* It also handles common gateways, such as IPFS and data URIs.
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*
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* @_section api/utils/fetching:Fetching Web Content [about-fetch]
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*/
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import { decodeBase64, encodeBase64 } from "./base64.js";
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import { hexlify } from "./data.js";
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import { assert, assertArgument } from "./errors.js";
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import { defineProperties } from "./properties.js";
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import { toUtf8Bytes, toUtf8String } from "./utf8.js";
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import { createGetUrl } from "./geturl.js";
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const MAX_ATTEMPTS = 12;
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const SLOT_INTERVAL = 250;
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// The global FetchGetUrlFunc implementation.
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let defaultGetUrlFunc = createGetUrl();
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const reData = new RegExp("^data:([^;:]*)?(;base64)?,(.*)$", "i");
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const reIpfs = new RegExp("^ipfs:/\/(ipfs/)?(.*)$", "i");
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// If locked, new Gateways cannot be added
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let locked = false;
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// https://developer.mozilla.org/en-US/docs/Web/HTTP/Basics_of_HTTP/Data_URLs
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async function dataGatewayFunc(url, signal) {
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try {
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const match = url.match(reData);
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if (!match) {
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throw new Error("invalid data");
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}
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return new FetchResponse(200, "OK", {
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"content-type": (match[1] || "text/plain"),
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}, (match[2] ? decodeBase64(match[3]) : unpercent(match[3])));
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}
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catch (error) {
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return new FetchResponse(599, "BAD REQUEST (invalid data: URI)", {}, null, new FetchRequest(url));
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}
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}
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/**
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* Returns a [[FetchGatewayFunc]] for fetching content from a standard
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* IPFS gateway hosted at %%baseUrl%%.
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*/
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function getIpfsGatewayFunc(baseUrl) {
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async function gatewayIpfs(url, signal) {
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try {
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const match = url.match(reIpfs);
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if (!match) {
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throw new Error("invalid link");
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}
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return new FetchRequest(`${baseUrl}${match[2]}`);
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}
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catch (error) {
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return new FetchResponse(599, "BAD REQUEST (invalid IPFS URI)", {}, null, new FetchRequest(url));
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}
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}
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return gatewayIpfs;
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}
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const Gateways = {
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"data": dataGatewayFunc,
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"ipfs": getIpfsGatewayFunc("https:/\/gateway.ipfs.io/ipfs/")
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};
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const fetchSignals = new WeakMap();
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/**
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* @_ignore
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*/
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export class FetchCancelSignal {
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#listeners;
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#cancelled;
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constructor(request) {
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this.#listeners = [];
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this.#cancelled = false;
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fetchSignals.set(request, () => {
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if (this.#cancelled) {
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return;
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}
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this.#cancelled = true;
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for (const listener of this.#listeners) {
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setTimeout(() => { listener(); }, 0);
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}
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this.#listeners = [];
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});
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}
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addListener(listener) {
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assert(!this.#cancelled, "singal already cancelled", "UNSUPPORTED_OPERATION", {
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operation: "fetchCancelSignal.addCancelListener"
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});
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this.#listeners.push(listener);
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}
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get cancelled() { return this.#cancelled; }
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checkSignal() {
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assert(!this.cancelled, "cancelled", "CANCELLED", {});
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}
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}
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// Check the signal, throwing if it is cancelled
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function checkSignal(signal) {
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if (signal == null) {
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throw new Error("missing signal; should not happen");
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}
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signal.checkSignal();
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return signal;
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}
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/**
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* Represents a request for a resource using a URI.
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*
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* By default, the supported schemes are ``HTTP``, ``HTTPS``, ``data:``,
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* and ``IPFS:``.
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*
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* Additional schemes can be added globally using [[registerGateway]].
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*
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* @example:
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* req = new FetchRequest("https://www.ricmoo.com")
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* resp = await req.send()
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* resp.body.length
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* //_result:
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*/
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export class FetchRequest {
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#allowInsecure;
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#gzip;
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#headers;
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#method;
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#timeout;
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#url;
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#body;
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#bodyType;
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#creds;
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// Hooks
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#preflight;
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#process;
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#retry;
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#signal;
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#throttle;
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#getUrlFunc;
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/**
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* The fetch URL to request.
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*/
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get url() { return this.#url; }
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set url(url) {
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this.#url = String(url);
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}
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/**
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* The fetch body, if any, to send as the request body. //(default: null)//
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*
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* When setting a body, the intrinsic ``Content-Type`` is automatically
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* set and will be used if **not overridden** by setting a custom
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* header.
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*
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* If %%body%% is null, the body is cleared (along with the
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* intrinsic ``Content-Type``).
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*
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* If %%body%% is a string, the intrinsic ``Content-Type`` is set to
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* ``text/plain``.
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*
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* If %%body%% is a Uint8Array, the intrinsic ``Content-Type`` is set to
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* ``application/octet-stream``.
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*
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* If %%body%% is any other object, the intrinsic ``Content-Type`` is
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* set to ``application/json``.
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*/
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get body() {
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if (this.#body == null) {
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return null;
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}
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return new Uint8Array(this.#body);
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}
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set body(body) {
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if (body == null) {
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this.#body = undefined;
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this.#bodyType = undefined;
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}
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else if (typeof (body) === "string") {
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this.#body = toUtf8Bytes(body);
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this.#bodyType = "text/plain";
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}
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else if (body instanceof Uint8Array) {
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this.#body = body;
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this.#bodyType = "application/octet-stream";
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}
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else if (typeof (body) === "object") {
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this.#body = toUtf8Bytes(JSON.stringify(body));
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this.#bodyType = "application/json";
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}
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else {
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throw new Error("invalid body");
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}
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}
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/**
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* Returns true if the request has a body.
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*/
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hasBody() {
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return (this.#body != null);
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}
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/**
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* The HTTP method to use when requesting the URI. If no method
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* has been explicitly set, then ``GET`` is used if the body is
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* null and ``POST`` otherwise.
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*/
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get method() {
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if (this.#method) {
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return this.#method;
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}
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if (this.hasBody()) {
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return "POST";
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}
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return "GET";
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}
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set method(method) {
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if (method == null) {
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method = "";
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}
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this.#method = String(method).toUpperCase();
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}
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/**
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* The headers that will be used when requesting the URI. All
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* keys are lower-case.
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*
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* This object is a copy, so any changes will **NOT** be reflected
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* in the ``FetchRequest``.
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*
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* To set a header entry, use the ``setHeader`` method.
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*/
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get headers() {
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const headers = Object.assign({}, this.#headers);
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if (this.#creds) {
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headers["authorization"] = `Basic ${encodeBase64(toUtf8Bytes(this.#creds))}`;
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}
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;
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if (this.allowGzip) {
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headers["accept-encoding"] = "gzip";
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}
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if (headers["content-type"] == null && this.#bodyType) {
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headers["content-type"] = this.#bodyType;
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}
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if (this.body) {
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headers["content-length"] = String(this.body.length);
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}
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return headers;
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}
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/**
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* Get the header for %%key%%, ignoring case.
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*/
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getHeader(key) {
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return this.headers[key.toLowerCase()];
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}
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/**
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* Set the header for %%key%% to %%value%%. All values are coerced
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* to a string.
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*/
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setHeader(key, value) {
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this.#headers[String(key).toLowerCase()] = String(value);
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}
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/**
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* Clear all headers, resetting all intrinsic headers.
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*/
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clearHeaders() {
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this.#headers = {};
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}
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[Symbol.iterator]() {
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const headers = this.headers;
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const keys = Object.keys(headers);
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let index = 0;
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return {
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next: () => {
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if (index < keys.length) {
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const key = keys[index++];
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return {
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value: [key, headers[key]], done: false
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};
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}
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return { value: undefined, done: true };
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}
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};
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}
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/**
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* The value that will be sent for the ``Authorization`` header.
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*
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* To set the credentials, use the ``setCredentials`` method.
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*/
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get credentials() {
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return this.#creds || null;
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}
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/**
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* Sets an ``Authorization`` for %%username%% with %%password%%.
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*/
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setCredentials(username, password) {
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assertArgument(!username.match(/:/), "invalid basic authentication username", "username", "[REDACTED]");
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this.#creds = `${username}:${password}`;
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}
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/**
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* Enable and request gzip-encoded responses. The response will
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* automatically be decompressed. //(default: true)//
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*/
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get allowGzip() {
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return this.#gzip;
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}
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set allowGzip(value) {
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this.#gzip = !!value;
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}
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/**
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* Allow ``Authentication`` credentials to be sent over insecure
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* channels. //(default: false)//
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*/
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get allowInsecureAuthentication() {
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return !!this.#allowInsecure;
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}
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set allowInsecureAuthentication(value) {
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this.#allowInsecure = !!value;
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}
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/**
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* The timeout (in milliseconds) to wait for a complete response.
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* //(default: 5 minutes)//
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*/
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get timeout() { return this.#timeout; }
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set timeout(timeout) {
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assertArgument(timeout >= 0, "timeout must be non-zero", "timeout", timeout);
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this.#timeout = timeout;
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}
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/**
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* This function is called prior to each request, for example
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* during a redirection or retry in case of server throttling.
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*
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* This offers an opportunity to populate headers or update
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* content before sending a request.
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*/
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get preflightFunc() {
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return this.#preflight || null;
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}
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set preflightFunc(preflight) {
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this.#preflight = preflight;
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}
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/**
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* This function is called after each response, offering an
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* opportunity to provide client-level throttling or updating
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* response data.
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*
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* Any error thrown in this causes the ``send()`` to throw.
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*
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* To schedule a retry attempt (assuming the maximum retry limit
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* has not been reached), use [[response.throwThrottleError]].
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*/
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get processFunc() {
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return this.#process || null;
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}
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set processFunc(process) {
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this.#process = process;
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}
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/**
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* This function is called on each retry attempt.
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*/
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get retryFunc() {
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return this.#retry || null;
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}
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set retryFunc(retry) {
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this.#retry = retry;
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}
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/**
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* This function is called to fetch content from HTTP and
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* HTTPS URLs and is platform specific (e.g. nodejs vs
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* browsers).
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*
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* This is by default the currently registered global getUrl
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* function, which can be changed using [[registerGetUrl]].
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* If this has been set, setting is to ``null`` will cause
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* this FetchRequest (and any future clones) to revert back to
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* using the currently registered global getUrl function.
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*
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* Setting this is generally not necessary, but may be useful
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* for developers that wish to intercept requests or to
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* configurege a proxy or other agent.
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*/
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get getUrlFunc() {
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return this.#getUrlFunc || defaultGetUrlFunc;
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}
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set getUrlFunc(value) {
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this.#getUrlFunc = value;
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}
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/**
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* Create a new FetchRequest instance with default values.
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*
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* Once created, each property may be set before issuing a
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* ``.send()`` to make the request.
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*/
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constructor(url) {
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this.#url = String(url);
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this.#allowInsecure = false;
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this.#gzip = true;
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this.#headers = {};
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this.#method = "";
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this.#timeout = 300000;
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this.#throttle = {
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slotInterval: SLOT_INTERVAL,
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maxAttempts: MAX_ATTEMPTS
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};
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this.#getUrlFunc = null;
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}
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toString() {
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return `<FetchRequest method=${JSON.stringify(this.method)} url=${JSON.stringify(this.url)} headers=${JSON.stringify(this.headers)} body=${this.#body ? hexlify(this.#body) : "null"}>`;
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}
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/**
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* Update the throttle parameters used to determine maximum
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* attempts and exponential-backoff properties.
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*/
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setThrottleParams(params) {
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if (params.slotInterval != null) {
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this.#throttle.slotInterval = params.slotInterval;
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}
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if (params.maxAttempts != null) {
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this.#throttle.maxAttempts = params.maxAttempts;
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}
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}
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async #send(attempt, expires, delay, _request, _response) {
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if (attempt >= this.#throttle.maxAttempts) {
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return _response.makeServerError("exceeded maximum retry limit");
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}
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assert(getTime() <= expires, "timeout", "TIMEOUT", {
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operation: "request.send", reason: "timeout", request: _request
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});
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if (delay > 0) {
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await wait(delay);
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}
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let req = this.clone();
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const scheme = (req.url.split(":")[0] || "").toLowerCase();
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// Process any Gateways
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if (scheme in Gateways) {
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const result = await Gateways[scheme](req.url, checkSignal(_request.#signal));
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if (result instanceof FetchResponse) {
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let response = result;
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if (this.processFunc) {
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checkSignal(_request.#signal);
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try {
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response = await this.processFunc(req, response);
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}
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catch (error) {
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// Something went wrong during processing; throw a 5xx server error
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if (error.throttle == null || typeof (error.stall) !== "number") {
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response.makeServerError("error in post-processing function", error).assertOk();
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}
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// Ignore throttling
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}
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}
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return response;
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}
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req = result;
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}
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// We have a preflight function; update the request
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if (this.preflightFunc) {
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req = await this.preflightFunc(req);
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}
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const resp = await this.getUrlFunc(req, checkSignal(_request.#signal));
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let response = new FetchResponse(resp.statusCode, resp.statusMessage, resp.headers, resp.body, _request);
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if (response.statusCode === 301 || response.statusCode === 302) {
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// Redirect
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try {
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const location = response.headers.location || "";
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return req.redirect(location).#send(attempt + 1, expires, 0, _request, response);
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}
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catch (error) { }
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// Things won't get any better on another attempt; abort
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return response;
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}
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else if (response.statusCode === 429) {
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// Throttle
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if (this.retryFunc == null || (await this.retryFunc(req, response, attempt))) {
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const retryAfter = response.headers["retry-after"];
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let delay = this.#throttle.slotInterval * Math.trunc(Math.random() * Math.pow(2, attempt));
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if (typeof (retryAfter) === "string" && retryAfter.match(/^[1-9][0-9]*$/)) {
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delay = parseInt(retryAfter);
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}
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return req.clone().#send(attempt + 1, expires, delay, _request, response);
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}
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}
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if (this.processFunc) {
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checkSignal(_request.#signal);
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try {
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response = await this.processFunc(req, response);
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}
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catch (error) {
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// Something went wrong during processing; throw a 5xx server error
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if (error.throttle == null || typeof (error.stall) !== "number") {
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response.makeServerError("error in post-processing function", error).assertOk();
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}
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// Throttle
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let delay = this.#throttle.slotInterval * Math.trunc(Math.random() * Math.pow(2, attempt));
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;
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if (error.stall >= 0) {
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delay = error.stall;
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}
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return req.clone().#send(attempt + 1, expires, delay, _request, response);
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}
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}
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return response;
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}
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/**
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* Resolves to the response by sending the request.
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*/
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send() {
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assert(this.#signal == null, "request already sent", "UNSUPPORTED_OPERATION", { operation: "fetchRequest.send" });
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this.#signal = new FetchCancelSignal(this);
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return this.#send(0, getTime() + this.timeout, 0, this, new FetchResponse(0, "", {}, null, this));
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}
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/**
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* Cancels the inflight response, causing a ``CANCELLED``
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* error to be rejected from the [[send]].
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*/
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cancel() {
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assert(this.#signal != null, "request has not been sent", "UNSUPPORTED_OPERATION", { operation: "fetchRequest.cancel" });
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const signal = fetchSignals.get(this);
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if (!signal) {
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throw new Error("missing signal; should not happen");
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}
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signal();
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}
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/**
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* Returns a new [[FetchRequest]] that represents the redirection
|
|
* to %%location%%.
|
|
*/
|
|
redirect(location) {
|
|
// Redirection; for now we only support absolute locations
|
|
const current = this.url.split(":")[0].toLowerCase();
|
|
const target = location.split(":")[0].toLowerCase();
|
|
// Don't allow redirecting:
|
|
// - non-GET requests
|
|
// - downgrading the security (e.g. https => http)
|
|
// - to non-HTTP (or non-HTTPS) protocols [this could be relaxed?]
|
|
assert(this.method === "GET" && (current !== "https" || target !== "http") && location.match(/^https?:/), `unsupported redirect`, "UNSUPPORTED_OPERATION", {
|
|
operation: `redirect(${this.method} ${JSON.stringify(this.url)} => ${JSON.stringify(location)})`
|
|
});
|
|
// Create a copy of this request, with a new URL
|
|
const req = new FetchRequest(location);
|
|
req.method = "GET";
|
|
req.allowGzip = this.allowGzip;
|
|
req.timeout = this.timeout;
|
|
req.#headers = Object.assign({}, this.#headers);
|
|
if (this.#body) {
|
|
req.#body = new Uint8Array(this.#body);
|
|
}
|
|
req.#bodyType = this.#bodyType;
|
|
// Do not forward credentials unless on the same domain; only absolute
|
|
//req.allowInsecure = false;
|
|
// paths are currently supported; may want a way to specify to forward?
|
|
//setStore(req.#props, "creds", getStore(this.#pros, "creds"));
|
|
return req;
|
|
}
|
|
/**
|
|
* Create a new copy of this request.
|
|
*/
|
|
clone() {
|
|
const clone = new FetchRequest(this.url);
|
|
// Preserve "default method" (i.e. null)
|
|
clone.#method = this.#method;
|
|
// Preserve "default body" with type, copying the Uint8Array is present
|
|
if (this.#body) {
|
|
clone.#body = this.#body;
|
|
}
|
|
clone.#bodyType = this.#bodyType;
|
|
// Preserve "default headers"
|
|
clone.#headers = Object.assign({}, this.#headers);
|
|
// Credentials is readonly, so we copy internally
|
|
clone.#creds = this.#creds;
|
|
if (this.allowGzip) {
|
|
clone.allowGzip = true;
|
|
}
|
|
clone.timeout = this.timeout;
|
|
if (this.allowInsecureAuthentication) {
|
|
clone.allowInsecureAuthentication = true;
|
|
}
|
|
clone.#preflight = this.#preflight;
|
|
clone.#process = this.#process;
|
|
clone.#retry = this.#retry;
|
|
clone.#throttle = Object.assign({}, this.#throttle);
|
|
clone.#getUrlFunc = this.#getUrlFunc;
|
|
return clone;
|
|
}
|
|
/**
|
|
* Locks all static configuration for gateways and FetchGetUrlFunc
|
|
* registration.
|
|
*/
|
|
static lockConfig() {
|
|
locked = true;
|
|
}
|
|
/**
|
|
* Get the current Gateway function for %%scheme%%.
|
|
*/
|
|
static getGateway(scheme) {
|
|
return Gateways[scheme.toLowerCase()] || null;
|
|
}
|
|
/**
|
|
* Use the %%func%% when fetching URIs using %%scheme%%.
|
|
*
|
|
* This method affects all requests globally.
|
|
*
|
|
* If [[lockConfig]] has been called, no change is made and this
|
|
* throws.
|
|
*/
|
|
static registerGateway(scheme, func) {
|
|
scheme = scheme.toLowerCase();
|
|
if (scheme === "http" || scheme === "https") {
|
|
throw new Error(`cannot intercept ${scheme}; use registerGetUrl`);
|
|
}
|
|
if (locked) {
|
|
throw new Error("gateways locked");
|
|
}
|
|
Gateways[scheme] = func;
|
|
}
|
|
/**
|
|
* Use %%getUrl%% when fetching URIs over HTTP and HTTPS requests.
|
|
*
|
|
* This method affects all requests globally.
|
|
*
|
|
* If [[lockConfig]] has been called, no change is made and this
|
|
* throws.
|
|
*/
|
|
static registerGetUrl(getUrl) {
|
|
if (locked) {
|
|
throw new Error("gateways locked");
|
|
}
|
|
defaultGetUrlFunc = getUrl;
|
|
}
|
|
/**
|
|
* Creates a getUrl function that fetches content from HTTP and
|
|
* HTTPS URLs.
|
|
*
|
|
* The available %%options%% are dependent on the platform
|
|
* implementation of the default getUrl function.
|
|
*
|
|
* This is not generally something that is needed, but is useful
|
|
* when trying to customize simple behaviour when fetching HTTP
|
|
* content.
|
|
*/
|
|
static createGetUrlFunc(options) {
|
|
return createGetUrl(options);
|
|
}
|
|
/**
|
|
* Creates a function that can "fetch" data URIs.
|
|
*
|
|
* Note that this is automatically done internally to support
|
|
* data URIs, so it is not necessary to register it.
|
|
*
|
|
* This is not generally something that is needed, but may
|
|
* be useful in a wrapper to perfom custom data URI functionality.
|
|
*/
|
|
static createDataGateway() {
|
|
return dataGatewayFunc;
|
|
}
|
|
/**
|
|
* Creates a function that will fetch IPFS (unvalidated) from
|
|
* a custom gateway baseUrl.
|
|
*
|
|
* The default IPFS gateway used internally is
|
|
* ``"https:/\/gateway.ipfs.io/ipfs/"``.
|
|
*/
|
|
static createIpfsGatewayFunc(baseUrl) {
|
|
return getIpfsGatewayFunc(baseUrl);
|
|
}
|
|
}
|
|
;
|
|
/**
|
|
* The response for a FetchRequest.
|
|
*/
|
|
export class FetchResponse {
|
|
#statusCode;
|
|
#statusMessage;
|
|
#headers;
|
|
#body;
|
|
#request;
|
|
#error;
|
|
toString() {
|
|
return `<FetchResponse status=${this.statusCode} body=${this.#body ? hexlify(this.#body) : "null"}>`;
|
|
}
|
|
/**
|
|
* The response status code.
|
|
*/
|
|
get statusCode() { return this.#statusCode; }
|
|
/**
|
|
* The response status message.
|
|
*/
|
|
get statusMessage() { return this.#statusMessage; }
|
|
/**
|
|
* The response headers. All keys are lower-case.
|
|
*/
|
|
get headers() { return Object.assign({}, this.#headers); }
|
|
/**
|
|
* The response body, or ``null`` if there was no body.
|
|
*/
|
|
get body() {
|
|
return (this.#body == null) ? null : new Uint8Array(this.#body);
|
|
}
|
|
/**
|
|
* The response body as a UTF-8 encoded string, or the empty
|
|
* string (i.e. ``""``) if there was no body.
|
|
*
|
|
* An error is thrown if the body is invalid UTF-8 data.
|
|
*/
|
|
get bodyText() {
|
|
try {
|
|
return (this.#body == null) ? "" : toUtf8String(this.#body);
|
|
}
|
|
catch (error) {
|
|
assert(false, "response body is not valid UTF-8 data", "UNSUPPORTED_OPERATION", {
|
|
operation: "bodyText", info: { response: this }
|
|
});
|
|
}
|
|
}
|
|
/**
|
|
* The response body, decoded as JSON.
|
|
*
|
|
* An error is thrown if the body is invalid JSON-encoded data
|
|
* or if there was no body.
|
|
*/
|
|
get bodyJson() {
|
|
try {
|
|
return JSON.parse(this.bodyText);
|
|
}
|
|
catch (error) {
|
|
assert(false, "response body is not valid JSON", "UNSUPPORTED_OPERATION", {
|
|
operation: "bodyJson", info: { response: this }
|
|
});
|
|
}
|
|
}
|
|
[Symbol.iterator]() {
|
|
const headers = this.headers;
|
|
const keys = Object.keys(headers);
|
|
let index = 0;
|
|
return {
|
|
next: () => {
|
|
if (index < keys.length) {
|
|
const key = keys[index++];
|
|
return {
|
|
value: [key, headers[key]], done: false
|
|
};
|
|
}
|
|
return { value: undefined, done: true };
|
|
}
|
|
};
|
|
}
|
|
constructor(statusCode, statusMessage, headers, body, request) {
|
|
this.#statusCode = statusCode;
|
|
this.#statusMessage = statusMessage;
|
|
this.#headers = Object.keys(headers).reduce((accum, k) => {
|
|
accum[k.toLowerCase()] = String(headers[k]);
|
|
return accum;
|
|
}, {});
|
|
this.#body = ((body == null) ? null : new Uint8Array(body));
|
|
this.#request = (request || null);
|
|
this.#error = { message: "" };
|
|
}
|
|
/**
|
|
* Return a Response with matching headers and body, but with
|
|
* an error status code (i.e. 599) and %%message%% with an
|
|
* optional %%error%%.
|
|
*/
|
|
makeServerError(message, error) {
|
|
let statusMessage;
|
|
if (!message) {
|
|
message = `${this.statusCode} ${this.statusMessage}`;
|
|
statusMessage = `CLIENT ESCALATED SERVER ERROR (${message})`;
|
|
}
|
|
else {
|
|
statusMessage = `CLIENT ESCALATED SERVER ERROR (${this.statusCode} ${this.statusMessage}; ${message})`;
|
|
}
|
|
const response = new FetchResponse(599, statusMessage, this.headers, this.body, this.#request || undefined);
|
|
response.#error = { message, error };
|
|
return response;
|
|
}
|
|
/**
|
|
* If called within a [request.processFunc](FetchRequest-processFunc)
|
|
* call, causes the request to retry as if throttled for %%stall%%
|
|
* milliseconds.
|
|
*/
|
|
throwThrottleError(message, stall) {
|
|
if (stall == null) {
|
|
stall = -1;
|
|
}
|
|
else {
|
|
assertArgument(Number.isInteger(stall) && stall >= 0, "invalid stall timeout", "stall", stall);
|
|
}
|
|
const error = new Error(message || "throttling requests");
|
|
defineProperties(error, { stall, throttle: true });
|
|
throw error;
|
|
}
|
|
/**
|
|
* Get the header value for %%key%%, ignoring case.
|
|
*/
|
|
getHeader(key) {
|
|
return this.headers[key.toLowerCase()];
|
|
}
|
|
/**
|
|
* Returns true if the response has a body.
|
|
*/
|
|
hasBody() {
|
|
return (this.#body != null);
|
|
}
|
|
/**
|
|
* The request made for this response.
|
|
*/
|
|
get request() { return this.#request; }
|
|
/**
|
|
* Returns true if this response was a success statusCode.
|
|
*/
|
|
ok() {
|
|
return (this.#error.message === "" && this.statusCode >= 200 && this.statusCode < 300);
|
|
}
|
|
/**
|
|
* Throws a ``SERVER_ERROR`` if this response is not ok.
|
|
*/
|
|
assertOk() {
|
|
if (this.ok()) {
|
|
return;
|
|
}
|
|
let { message, error } = this.#error;
|
|
if (message === "") {
|
|
message = `server response ${this.statusCode} ${this.statusMessage}`;
|
|
}
|
|
let requestUrl = null;
|
|
if (this.request) {
|
|
requestUrl = this.request.url;
|
|
}
|
|
let responseBody = null;
|
|
try {
|
|
if (this.#body) {
|
|
responseBody = toUtf8String(this.#body);
|
|
}
|
|
}
|
|
catch (e) { }
|
|
assert(false, message, "SERVER_ERROR", {
|
|
request: (this.request || "unknown request"), response: this, error,
|
|
info: {
|
|
requestUrl, responseBody,
|
|
responseStatus: `${this.statusCode} ${this.statusMessage}`
|
|
}
|
|
});
|
|
}
|
|
}
|
|
function getTime() { return (new Date()).getTime(); }
|
|
function unpercent(value) {
|
|
return toUtf8Bytes(value.replace(/%([0-9a-f][0-9a-f])/gi, (all, code) => {
|
|
return String.fromCharCode(parseInt(code, 16));
|
|
}));
|
|
}
|
|
function wait(delay) {
|
|
return new Promise((resolve) => setTimeout(resolve, delay));
|
|
}
|
|
//# sourceMappingURL=fetch.js.map
|