From ece7ffadd6b5660872636276851913529b8c3a70 Mon Sep 17 00:00:00 2001
From: Laurent Cozic <laurent@cozic.net>
Date: Wed, 28 Oct 2020 15:47:36 +0000
Subject: [PATCH] Desktop: Fixes #3986: Handle gzipped CSS files when importing
 from clipper

---
 ReactNativeClient/lib/shim-init-node.js  | 57 +++++++++++++++++++++++-
 ReactNativeClient/lib/shim-init-react.js | 22 ++++++---
 2 files changed, 71 insertions(+), 8 deletions(-)

diff --git a/ReactNativeClient/lib/shim-init-node.js b/ReactNativeClient/lib/shim-init-node.js
index 235817a90a..7046d0be3c 100644
--- a/ReactNativeClient/lib/shim-init-node.js
+++ b/ReactNativeClient/lib/shim-init-node.js
@@ -13,6 +13,43 @@ const http = require('http');
 const https = require('https');
 const toRelative = require('relative');
 const timers = require('timers');
+const zlib = require('zlib');
+
+function fileExists(filePath) {
+	try {
+		return fs.statSync(filePath).isFile();
+	} catch (err) {
+		return false;
+	}
+}
+
+const gunzipFile = function(source, destination) {
+	if (!fileExists(source)) {
+		throw new Error(`No such file: ${source}`);
+	}
+
+	return new Promise((resolve, reject) => {
+		// prepare streams
+		const src = fs.createReadStream(source);
+		const dest = fs.createWriteStream(destination);
+
+		// extract the archive
+		src.pipe(zlib.createGunzip()).pipe(dest);
+
+		// callback on extract completion
+		dest.on('close', function() {
+			resolve();
+		});
+
+		src.on('error', () => {
+			reject();
+		});
+
+		dest.on('error', () => {
+			reject();
+		});
+	});
+};
 
 function shimInit() {
 	shim.fsDriver = () => {
@@ -365,9 +402,25 @@ function shimInit() {
 					const request = http.request(requestOptions, function(response) {
 						response.pipe(file);
 
+						const isGzipped = response.headers['content-encoding'] === 'gzip';
+
 						file.on('finish', function() {
-							file.close(() => {
-								resolve(makeResponse(response));
+							file.close(async () => {
+								if (isGzipped) {
+									const gzipFilePath = `${filePath}.gzip`;
+									await shim.fsDriver().move(filePath, gzipFilePath);
+
+									try {
+										await gunzipFile(gzipFilePath, filePath);
+										resolve(makeResponse(response));
+									} catch (error) {
+										cleanUpOnError(error);
+									}
+
+									shim.fsDriver().remove(gzipFilePath);
+								} else {
+									resolve(makeResponse(response));
+								}
 							});
 						});
 					});
diff --git a/ReactNativeClient/lib/shim-init-react.js b/ReactNativeClient/lib/shim-init-react.js
index 9f5a6b6081..a8ac2dd346 100644
--- a/ReactNativeClient/lib/shim-init-react.js
+++ b/ReactNativeClient/lib/shim-init-react.js
@@ -36,21 +36,31 @@ function shimInit() {
 	};
 
 	shim.fetch = async function(url, options = null) {
-		// The native fetch() throws an uncatable error that crashes the app if calling it with an
-		// invalid URL such as '//.resource' or "http://ocloud. de" so detect if the URL is valid beforehand
-		// and throw a catchable error.
-		// Bug: https://github.com/facebook/react-native/issues/7436
+		// The native fetch() throws an uncatchable error that crashes the
+		// app if calling it with an invalid URL such as '//.resource' or
+		// "http://ocloud. de" so detect if the URL is valid beforehand and
+		// throw a catchable error. Bug:
+		// https://github.com/facebook/react-native/issues/7436
 		const validatedUrl = urlValidator.isUri(url);
 		if (!validatedUrl) throw new Error(`Not a valid URL: ${url}`);
 
 		return shim.fetchWithRetry(() => {
-			// If the request has a body and it's not a GET call, and it doesn't have a Content-Type header
-			// we display a warning, because it could trigger a "Network request failed" error.
+			// If the request has a body and it's not a GET call, and it
+			// doesn't have a Content-Type header we display a warning,
+			// because it could trigger a "Network request failed" error.
 			// https://github.com/facebook/react-native/issues/30176
 			if (options?.body && options?.method && options.method !== 'GET' && !options?.headers?.['Content-Type']) {
 				console.warn('Done a non-GET fetch call without a Content-Type header. It may make the request fail.', url, options);
 			}
 
+			// Among React Native `fetch()` many bugs, one of them is that
+			// it will truncate strings when they contain binary data.
+			// Browser fetch() or Node fetch() work fine but as always RN's
+			// one doesn't. There's no obvious way to fix this so we'll
+			// have to wait if it's eventually fixed upstream. See here for
+			// more info:
+			// https://github.com/laurent22/joplin/issues/3986#issuecomment-718019688
+
 			return fetch(validatedUrl, options);
 		}, options);
 	};