refactor targz logic into separate file

src/storage/targz.js

@@ -0,0 +1,112 @@
+'use strict';
+
+exports = module.exports = {
+    create: create,
+    extract: extract
+};
+
+var assert = require('assert'),
+    BackupsError = require('../backups.js').BackupsError,
+    crypto = require('crypto'),
+    debug = require('debug')('box:storage/filesystem'),
+    mkdirp = require('mkdirp'),
+    progress = require('progress-stream'),
+    spawn = require('child_process').spawn,
+    tar = require('tar-fs'),
+    zlib = require('zlib');
+
+function create(sourceDirectories, key, outStream, callback) {
+    assert(Array.isArray(sourceDirectories));
+    assert.strictEqual(typeof key, 'string');
+    assert.strictEqual(typeof callback, 'function');
+
+    var pack = tar.pack('/', {
+        entries: sourceDirectories.map(function (m) { return m.source; }),
+        map: function(header) {
+            sourceDirectories.forEach(function (m) {
+                header.name = header.name.replace(new RegExp('^' + m.source + '(/?)'), m.destination + '$1');
+            });
+            return header;
+        }
+    });
+
+    var gzip = zlib.createGzip({});
+    var encrypt = crypto.createCipher('aes-256-cbc', key);
+    var progressStream = progress({ time: 10000 }); // display a progress every 10 seconds
+
+    pack.on('error', function (error) {
+        console.error('backup: tar stream error.', error);
+        callback(new BackupsError(BackupsError.EXTERNAL_ERROR, error.message));
+    });
+
+    gzip.on('error', function (error) {
+        console.error('backup: gzip stream error.', error);
+        callback(new BackupsError(BackupsError.EXTERNAL_ERROR, error.message));
+    });
+
+    encrypt.on('error', function (error) {
+        console.error('backup: encrypt stream error.', error);
+        callback(new BackupsError(BackupsError.EXTERNAL_ERROR, error.message));
+    });
+
+    progressStream.on('progress', function(progress) {
+        debug('backup: %s@%s', Math.round(progress.transferred/1024/1024) + 'M', Math.round(progress.speed/1024/1024) + 'Mbps');
+    });
+
+    pack.pipe(gzip).pipe(encrypt).pipe(progressStream).pipe(outStream);
+}
+
+function extract(inStream, isOldFormat, destination, key, callback) {
+    assert.strictEqual(typeof isOldFormat, 'boolean');
+    assert.strictEqual(typeof destination, 'string');
+    assert.strictEqual(typeof key, 'string');
+    assert.strictEqual(typeof callback, 'function');
+
+    mkdirp(destination, function (error) {
+        if (error) return callback(new BackupsError(BackupsError.EXTERNAL_ERROR, error.message));
+
+        var decrypt;
+
+        if (isOldFormat) {
+            let args = ['aes-256-cbc', '-d', '-pass', 'pass:' + key];
+            decrypt = spawn('openssl', args, { stdio: [ 'pipe', 'pipe', process.stderr ]});
+        } else {
+            decrypt = crypto.createDecipher('aes-256-cbc', key);
+        }
+
+        var gunzip = zlib.createGunzip({});
+        var progressStream = progress({ time: 10000 }); // display a progress every 10 seconds
+        var extract = tar.extract(destination);
+
+        progressStream.on('progress', function(progress) {
+            debug('restore: %s@%s', Math.round(progress.transferred/1024/1024) + 'M', Math.round(progress.speed/1024/1024) + 'Mbps');
+        });
+
+        decrypt.on('error', function (error) {
+            console.error('restore: decrypt stream error.', error);
+            callback(new BackupsError(BackupsError.EXTERNAL_ERROR, error.message));
+        });
+
+        gunzip.on('error', function (error) {
+            console.error('restore: gunzip stream error.', error);
+            callback(new BackupsError(BackupsError.EXTERNAL_ERROR, error.message));
+        });
+
+        extract.on('error', function (error) {
+            console.error('restore: extract stream error.', error);
+            callback(new BackupsError(BackupsError.EXTERNAL_ERROR, error.message));
+        });
+
+        extract.on('finish', function () {
+            debug('restore: done.');
+            callback(null);
+        });
+
+        if (isOldFormat) {
+            inStream.pipe(progressStream).pipe(decrypt.stdin);
+            decrypt.stdout.pipe(gunzip).pipe(extract);
+        } else {
+            inStream.pipe(progressStream).pipe(decrypt).pipe(gunzip).pipe(extract);
+        }
+    });
+}