storage: make remove and removeDir async

src/storage/gcs.js

@@ -34,7 +34,8 @@ const assert = require('assert'),
     EventEmitter = require('events'),
     PassThrough = require('stream').PassThrough,
     path = require('path'),
-    safe = require('safetydance');
+    safe = require('safetydance'),
+    util = require('util');
 
 let GCS = require('@google-cloud/storage').Storage;
 
@@ -221,44 +222,32 @@ function copy(apiConfig, oldFilePath, newFilePath) {
     return events;
 }
 
-function remove(apiConfig, filename, callback) {
+async function remove(apiConfig, filename) {
     assert.strictEqual(typeof apiConfig, 'object');
     assert.strictEqual(typeof filename, 'string');
-    assert.strictEqual(typeof callback, 'function');
 
-    getBucket(apiConfig)
-        .file(filename)
-        .delete(function (error) {
-            if (error) debug('removeBackups: Unable to remove %s (%s). Not fatal.', filename, error.message);
-
-            callback(null);
-        });
+    const [error] = await safe(getBucket(apiConfig).file(filename).delete());
+    if (error) debug('removeBackups: Unable to remove %s (%s). Not fatal.', filename, error.message);
 }
 
-function removeDir(apiConfig, pathPrefix) {
+async function removeDir(apiConfig, pathPrefix, progressCallback) {
     assert.strictEqual(typeof apiConfig, 'object');
     assert.strictEqual(typeof pathPrefix, 'string');
-
-    var events = new EventEmitter();
+    assert.strictEqual(typeof progressCallback, 'function');
 
     const batchSize = 1000, concurrency = apiConfig.deleteConcurrency || 10; // https://googleapis.dev/nodejs/storage/latest/Bucket.html#deleteFiles
-    var total = 0;
+    let total = 0;
 
-    listDir(apiConfig, pathPrefix, batchSize, function (entries, done) {
+    const listDirAsync = util.promisify(listDir);
+
+    await listDirAsync(apiConfig, pathPrefix, batchSize, function (entries, done) {
         total += entries.length;
 
-        events.emit('progress', `Removing ${entries.length} files from ${entries[0].fullPath} to ${entries[entries.length-1].fullPath}. total: ${total}`);
+        progressCallback({ message: `Removing ${entries.length} files from ${entries[0].fullPath} to ${entries[entries.length-1].fullPath}. total: ${total}` });
 
-        async.eachLimit(entries, concurrency, function (entry, iteratorCallback) {
-            remove(apiConfig, entry.fullPath, iteratorCallback);
-        }, done);
-    }, function (error) {
-        events.emit('progress', `Deleted ${total} files`);
-
-        process.nextTick(() => events.emit('done', error));
+        async.eachLimit(entries, concurrency, async (entry) => await remove(apiConfig, entry.fullPath), done);
     });
-
-    return events;
+    progressCallback({ progress: `Deleted ${total} files` });
 }
 
 async function remount(apiConfig) {