huksley/decodeGoogleNewsUrl.ts

## decodeGoogleNewsUrl.ts
/**
 * Google News started generate encoded, internal URLs for RSS items
 * https://news.google.com/rss/search?q=New%20York%20when%3A30d&hl=en-US&gl=US&ceid=US:en
 *
 * This script decodes URLs into original one, for example URL
 * https://news.google.com/__i/rss/rd/articles/CBMiSGh0dHBzOi8vdGVjaGNydW5jaC5jb20vMjAyMi8xMC8yNy9uZXcteW9yay1wb3N0LWhhY2tlZC1vZmZlbnNpdmUtdHdlZXRzL9IBAA?oc=5
 *
 * contains this
 * https://techcrunch.com/2022/10/27/new-york-post-hacked-offensive-tweets/
 *
 * In path after articles/ goes Base64 encoded binary data
 *
 * Format is the following:
 * <prefix> <len bytes> <URL bytes> <len bytes> <amp URL bytes> [<suffix>]
 *
 * <prefix> - 0x08, 0x13, 0x22
 * <suffix> - 0xd2, 0x01, 0x00 (sometimes missing??)
 * <len bytes> - formatted as 0x40 or 0x81 0x01 sometimes
 *
 * FIXME: What will happen if URL more than 255 bytes??
 *
 * Licensed under: MIT License
 *
 * Copyright (c) 2022 Ruslan Gainutdinov
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */
const decodeGoogleNewsUrl = (sourceUrl: string) => {
  const url = new URL(sourceUrl);
  const path = url.pathname.split("/");
  if (url.hostname === "news.google.com" && path.length > 1 && path[path.length - 2] === "articles") {
    const base64 = path[path.length - 1];
    let str = atob(base64);

    const prefix = Buffer.from([0x08, 0x13, 0x22]).toString("binary");
    if (str.startsWith(prefix)) {
      str = str.substring(prefix.length);
    }

    const suffix = Buffer.from([0xd2, 0x01, 0x00]).toString("binary");
    if (str.endsWith(suffix)) {
      str = str.substring(0, str.length - suffix.length);
    }

    // One or two bytes to skip
    const bytes = Uint8Array.from(str, (c) => c.charCodeAt(0));
    const len = bytes.at(0)!;
    if (len >= 0x80) {
      str = str.substring(2, len + 1);
    } else {
      str = str.substring(1, len + 1);
    }

    return str;
  } else {
    return sourceUrl;
  }
};
	/**
	* Google News started generate encoded, internal URLs for RSS items
	* https://news.google.com/rss/search?q=New%20York%20when%3A30d&hl=en-US&gl=US&ceid=US:en
	*
	* This script decodes URLs into original one, for example URL
	* https://news.google.com/__i/rss/rd/articles/CBMiSGh0dHBzOi8vdGVjaGNydW5jaC5jb20vMjAyMi8xMC8yNy9uZXcteW9yay1wb3N0LWhhY2tlZC1vZmZlbnNpdmUtdHdlZXRzL9IBAA?oc=5
	*
	* contains this
	* https://techcrunch.com/2022/10/27/new-york-post-hacked-offensive-tweets/
	*
	* In path after articles/ goes Base64 encoded binary data
	*
	* Format is the following:
	* <prefix> <len bytes> <URL bytes> <len bytes> <amp URL bytes> [<suffix>]
	*
	* <prefix> - 0x08, 0x13, 0x22
	* <suffix> - 0xd2, 0x01, 0x00 (sometimes missing??)
	* <len bytes> - formatted as 0x40 or 0x81 0x01 sometimes
	*
	* FIXME: What will happen if URL more than 255 bytes??
	*
	* Licensed under: MIT License
	*
	* Copyright (c) 2022 Ruslan Gainutdinov
	*
	* Permission is hereby granted, free of charge, to any person obtaining a copy
	* of this software and associated documentation files (the "Software"), to deal
	* in the Software without restriction, including without limitation the rights
	* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
	* copies of the Software, and to permit persons to whom the Software is
	* furnished to do so, subject to the following conditions:
	*
	* The above copyright notice and this permission notice shall be included
	* in all copies or substantial portions of the Software.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
	* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
	* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
	* SOFTWARE.
	*/
	const decodeGoogleNewsUrl = (sourceUrl: string) => {
	const url = new URL(sourceUrl);
	const path = url.pathname.split("/");
	if (url.hostname === "news.google.com" && path.length > 1 && path[path.length - 2] === "articles") {
	const base64 = path[path.length - 1];
	let str = atob(base64);

	const prefix = Buffer.from([0x08, 0x13, 0x22]).toString("binary");
	if (str.startsWith(prefix)) {
	str = str.substring(prefix.length);
	}

	const suffix = Buffer.from([0xd2, 0x01, 0x00]).toString("binary");
	if (str.endsWith(suffix)) {
	str = str.substring(0, str.length - suffix.length);
	}

	// One or two bytes to skip
	const bytes = Uint8Array.from(str, (c) => c.charCodeAt(0));
	const len = bytes.at(0)!;
	if (len >= 0x80) {
	str = str.substring(2, len + 1);
	} else {
	str = str.substring(1, len + 1);
	}

	return str;
	} else {
	return sourceUrl;
	}
	};