feat(storage): support gs:// copy/move dests (#1416)

Fixes #1395

lib/storage/file.js

@@ -79,6 +79,12 @@ var STORAGE_DOWNLOAD_BASE_URL = 'https://storage.googleapis.com';
  */
 var STORAGE_UPLOAD_BASE_URL = 'https://www.googleapis.com/upload/storage/v1/b';
 
+/**
+ * @const {RegExp}
+ * @private
+ */
+var GS_URL_REGEXP = /^gs\:\/\/([a-z0-9_\.\-]+)\/(.+)$/;
+
 /*! Developer Documentation
  *
  * @param {module:storage/bucket} bucket - The Bucket instance this file is
@@ -284,7 +290,7 @@ nodeutil.inherits(File, ServiceObject);
 /**
  * Copy this file to another file. By default, this will copy the file to the
  * same bucket, but you can choose to copy it to another Bucket by providing
- * either a Bucket or File object.
+ * a Bucket or File object or a URL starting with "gs://".
  *
  * @resource [Objects: copy API Documentation]{@link https://cloud.google.com/storage/docs/json_api/v1/objects/copy}
  *
@@ -321,6 +327,22 @@ nodeutil.inherits(File, ServiceObject);
  * });
  *
  * //-
+ * // If you pass in a string starting with "gs://" for the destination, the
+ * // file is copied to the other bucket and under the new name provided.
+ * //-
+ * var newLocation = 'gs://another-bucket/my-image-copy.png';
+ * file.copy(newLocation, function(err, copiedFile, apiResponse) {
+ *   // `my-bucket` still contains:
+ *   // - "my-image.png"
+ *   //
+ *   // `another-bucket` now contains:
+ *   // - "my-image-copy.png"
+ *
+ *   // `copiedFile` is an instance of a File object that refers to your new
+ *   // file.
+ * });
+ *
+ * //-
  * // If you pass in a Bucket object, the file will be copied to that bucket
  * // using the same name.
  * //-
@@ -366,8 +388,14 @@ File.prototype.copy = function(destination, callback) {
   var newFile;
 
   if (is.string(destination)) {
-    destBucket = this.bucket;
-    destName = destination;
+    var parsedDestination = GS_URL_REGEXP.exec(destination);
+    if (parsedDestination !== null && parsedDestination.length === 3) {
+      destBucket = this.storage.bucket(parsedDestination[1]);
+      destName = parsedDestination[2];
+    } else {
+      destBucket = this.bucket;
+      destName = destination;
+    }
   } else if (destination.constructor &&
         destination.constructor.name === 'Bucket') {
     destBucket = destination;
@@ -1467,7 +1495,7 @@ File.prototype.makePublic = function(callback) {
 /**
  * Move this file to another location. By default, this will move the file to
  * the same bucket, but you can choose to move it to another Bucket by providing
- * either a Bucket or File object.
+ * a Bucket or File object or a URL beginning with "gs://".
  *
  * **Warning**:
  * There is currently no atomic `move` method in the Google Cloud Storage API,
@@ -1513,6 +1541,22 @@ File.prototype.makePublic = function(callback) {
  * });
  *
  * //-
+ * // If you pass in a string starting with "gs://" for the destination, the
+ * // file is copied to the other bucket and under the new name provided.
+ * //-
+ * var newLocation = 'gs://another-bucket/my-image-new.png';
+ * file.move(newLocation, function(err, destinationFile, apiResponse) {
+ *   // `my-bucket` no longer contains:
+ *   // - "my-image.png"
+ *   //
+ *   // `another-bucket` now contains:
+ *   // - "my-image-new.png"
+ *
+ *   // `destinationFile` is an instance of a File object that refers to your
+ *   // new file.
+ * });
+ *
+ * //-
  * // If you pass in a Bucket object, the file will be moved to that bucket
  * // using the same name.
  * //-

system-test/storage.js

@@ -849,13 +849,42 @@ describe('storage', function() {
         assert.ifError(err);
 
         file.copy('CloudLogoCopy', function(err, copiedFile) {
+          assert.ifError(err);
           async.parallel([
             file.delete.bind(file),
             copiedFile.delete.bind(copiedFile)
           ], done);
         });
       });
     });
+
+    it('should copy to another bucket given a gs:// URL', function(done) {
+      var opts = { destination: 'CloudLogo' };
+      bucket.upload(FILES.logo.path, opts, function(err, file) {
+        assert.ifError(err);
+
+        var otherBucket = storage.bucket(generateName());
+        otherBucket.create(function(err) {
+          assert.ifError(err);
+
+          var destPath = 'gs://' + otherBucket.name + '/CloudLogoCopy';
+          file.copy(destPath, function(err) {
+            assert.ifError(err);
+
+            otherBucket.getFiles(function(err, files) {
+              assert.ifError(err);
+
+              assert.strictEqual(files.length, 1);
+              var newFile = files[0];
+
+              assert.strictEqual(newFile.name, 'CloudLogoCopy');
+
+              done();
+            });
+          });
+        });
+      });
+    });
   });
 
   describe('channels', function() {

test/storage/file.js

@@ -125,6 +125,9 @@ describe('File', function() {
         } else {
           return (requestOverride || requestCached)(req);
         }
+      },
+      bucket: function(name) {
+        return new Bucket(this, name);
       }
     };
 
@@ -311,6 +314,16 @@ describe('File', function() {
         file.copy(newFileName);
       });
 
+      it('should allow a "gs://..." string', function(done) {
+        var newFileName = 'gs://other-bucket/new-file-name.png';
+        var expectedPath = format('/copyTo/b/{destBucket}/o/{destName}', {
+          destBucket: 'other-bucket',
+          destName: 'new-file-name.png'
+        });
+        assertPathEquals(file, expectedPath, done);
+        file.copy(newFileName);
+      });
+
       it('should allow a Bucket', function(done) {
         var expectedPath = format('/copyTo/b/{destBucket}/o/{destName}', {
           destBucket: BUCKET.name,