/* * Copyright (C) 2020 Yomichan Authors * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <https://www.gnu.org/licenses/>. */ class RequestBuilder { constructor() { this._extraHeadersSupported = null; this._onBeforeSendHeadersExtraInfoSpec = ['blocking', 'requestHeaders', 'extraHeaders']; } async fetchAnonymous(url, init) { const originURL = this._getOriginURL(url); const modifications = [ ['cookie', null], ['origin', {name: 'Origin', value: originURL}] ]; return await this._fetchModifyHeaders(url, init, modifications); } // Private async _fetchModifyHeaders(url, init, modifications) { const matchURL = this._getMatchURL(url); let done = false; const callback = (details) => { if (done || details.url !== url) { return {}; } done = true; const requestHeaders = details.requestHeaders; this._modifyHeaders(requestHeaders, modifications); return {requestHeaders}; }; const filter = { urls: [matchURL], types: ['xmlhttprequest'] }; let needsCleanup = false; try { this._onBeforeSendHeadersAddListener(callback, filter); needsCleanup = true; } catch (e) { // NOP } try { return await fetch(url, init); } finally { if (needsCleanup) { try { chrome.webRequest.onBeforeSendHeaders.removeListener(callback); } catch (e) { // NOP } } } } _onBeforeSendHeadersAddListener(callback, filter) { const extraInfoSpec = this._onBeforeSendHeadersExtraInfoSpec; for (let i = 0; i < 2; ++i) { try { chrome.webRequest.onBeforeSendHeaders.addListener(callback, filter, extraInfoSpec); if (this._extraHeadersSupported === null) { this._extraHeadersSupported = true; } break; } catch (e) { // Firefox doesn't support the 'extraHeaders' option and will throw the following error: // Type error for parameter extraInfoSpec (Error processing 2: Invalid enumeration value "extraHeaders") for webRequest.onBeforeSendHeaders. if (this._extraHeadersSupported !== null || !`${e.message}`.includes('extraHeaders')) { throw e; } } // addListener failed; remove 'extraHeaders' from extraInfoSpec. this._extraHeadersSupported = false; const index = extraInfoSpec.indexOf('extraHeaders'); if (index >= 0) { extraInfoSpec.splice(index, 1); } } } _getMatchURL(url) { const url2 = new URL(url); return `${url2.protocol}//${url2.host}${url2.pathname}`; } _getOriginURL(url) { const url2 = new URL(url); return `${url2.protocol}//${url2.host}`; } _modifyHeaders(headers, modifications) { modifications = new Map(modifications); for (let i = 0, ii = headers.length; i < ii; ++i) { const header = headers[i]; const name = header.name.toLowerCase(); const modification = modifications.get(name); if (typeof modification === 'undefined') { continue; } modifications.delete(name); if (modification === null) { headers.splice(i, 1); --i; --ii; } else { headers[i] = modification; } } for (const header of modifications.values()) { if (header !== null) { headers.push(header); } } } }