All: Added fs drivers and encryption service

ReactNativeClient/lib/fs-driver-rn.js

@@ -0,0 +1,64 @@
+const RNFS = require('react-native-fs');
+
+class FsDriverRN {
+
+	appendFileSync(path, string) {
+		throw new Error('Not implemented');
+	}
+
+	appendFile(path, string, encoding = 'base64') {
+		return RNFS.appendFile(path, string, encoding);
+	}
+
+	writeBinaryFile(path, content) {
+		throw new Error('Not implemented');
+	}
+
+	async open(path, mode) {
+		// Note: RNFS.read() doesn't provide any way to know if the end of file has been reached.
+		// So instead we stat the file here and use stat.size to manually check for end of file.
+		// Bug: https://github.com/itinance/react-native-fs/issues/342
+		const stat = await RNFS.stat(path);
+		return {
+			path: path,
+			offset: 0,
+			mode: mode,
+			stat: stat,
+		}
+	}
+
+	close(handler) {
+		return null;
+	}
+
+	readFile(path) {
+		throw new Error('Not implemented');
+	}
+
+	async unlink(path) {
+		try {
+			await RNFS.unlink(path);
+		} catch (error) {
+			if (error && error.message && error.message.indexOf('exist') >= 0) {
+				// Probably { [Error: File does not exist] framesToPop: 1, code: 'EUNSPECIFIED' }
+				// which unfortunately does not have a proper error code. Can be ignored.
+			} else {
+				throw error;
+			}
+		}
+	}
+
+	async readFileChunk(handle, length, encoding = 'base64') {
+		if (handle.offset + length > handle.stat.size) {
+			length = handle.stat.size - handle.offset;
+		}
+
+		if (!length) return null;
+		let output = await RNFS.read(handle.path, length, handle.offset, encoding);
+		handle.offset += length;
+		return output ? output : null;
+	}
+
+}
+
+module.exports.FsDriverRN = FsDriverRN;