update: implement --to-remote flag

dvc/command/update.py

@@ -16,6 +16,9 @@ def run(self):
                 targets=self.args.targets,
                 rev=self.args.rev,
                 recursive=self.args.recursive,
+                to_remote=self.args.to_remote,
+                remote=self.args.remote,
+                jobs=self.args.jobs,
             )
         except DvcException:
             logger.exception("failed update data")
@@ -48,4 +51,27 @@ def add_parser(subparsers, parent_parser):
         default=False,
         help="Update all stages in the specified directory.",
     )
+    update_parser.add_argument(
+        "--to-remote",
+        action="store_true",
+        default=False,
+        help="Update data directly on the remote",
+    )
+    update_parser.add_argument(
+        "-r",
+        "--remote",
+        help="Remote storage to perform updates to",
+        metavar="<name>",
+    )
+    update_parser.add_argument(
+        "-j",
+        "--jobs",
+        type=int,
+        help=(
+            "Number of jobs to run simultaneously. "
+            "The default value is 4 * cpu_count(). "
+            "For SSH remotes, the default is 4. "
+        ),
+        metavar="<number>",
+    )
     update_parser.set_defaults(func=CmdUpdate)

dvc/repo/update.py

@@ -2,7 +2,15 @@
 
 
 @locked
-def update(self, targets=None, rev=None, recursive=False):
+def update(
+    self,
+    targets=None,
+    rev=None,
+    recursive=False,
+    to_remote=False,
+    remote=None,
+    jobs=None,
+):
     from ..dvcfile import Dvcfile
 
     if not targets:
@@ -16,7 +24,7 @@ def update(self, targets=None, rev=None, recursive=False):
         stages.update(self.stage.collect(target, recursive=recursive))
 
     for stage in stages:
-        stage.update(rev)
+        stage.update(rev, to_remote=to_remote, remote=remote, jobs=jobs)
         dvcfile = Dvcfile(self, stage.path)
         dvcfile.dump(stage)
         stages.add(stage)

dvc/stage/__init__.py

@@ -411,10 +411,12 @@ def reproduce(self, interactive=False, **kwargs):
 
         return self
 
-    def update(self, rev=None):
+    def update(self, rev=None, to_remote=False, remote=None, jobs=None):
         if not (self.is_repo_import or self.is_import):
             raise StageUpdateError(self.relpath)
-        update_import(self, rev=rev)
+        update_import(
+            self, rev=rev, to_remote=to_remote, remote=remote, jobs=jobs
+        )
 
     @property
     def can_be_skipped(self):

dvc/stage/imports.py

@@ -3,12 +3,22 @@
 logger = logging.getLogger(__name__)
 
 
-def update_import(stage, rev=None):
+def _update_import_on_remote(stage, remote, jobs):
+    url = stage.deps[0].path_info.url
+    stage.outs[0].hash_info = stage.repo.cloud.transfer(
+        url, jobs=jobs, remote=remote, command="update"
+    )
+
+
+def update_import(stage, rev=None, to_remote=False, remote=None, jobs=None):
     stage.deps[0].update(rev=rev)
     frozen = stage.frozen
     stage.frozen = False
     try:
-        stage.reproduce()
+        if to_remote:
+            _update_import_on_remote(stage, remote, jobs)
+        else:
+            stage.reproduce()
     finally:
         stage.frozen = frozen
 

tests/func/test_update.py

@@ -315,3 +315,51 @@ def test_update_from_subrepos(tmp_dir, dvc, erepo_dir, is_dvc):
         "url": repo_path,
         "rev_lock": erepo_dir.scm.get_rev(),
     }
+
+
+@pytest.mark.parametrize(
+    "workspace",
+    [
+        pytest.lazy_fixture("local_cloud"),
+        pytest.lazy_fixture("s3"),
+        pytest.lazy_fixture("gs"),
+        pytest.lazy_fixture("hdfs"),
+    ],
+    indirect=True,
+)
+def test_update_import_url_to_remote(tmp_dir, dvc, workspace, local_remote):
+    workspace.gen("foo", "foo")
+    stage = dvc.imp_url("remote://workspace/foo", to_remote=True)
+
+    workspace.gen("foo", "bar")
+    stage = dvc.update(stage.path, to_remote=True)
+
+    dvc.pull("foo")
+    assert (tmp_dir / "foo").read_text() == "bar"
+
+
+@pytest.mark.parametrize(
+    "workspace",
+    [
+        pytest.lazy_fixture("local_cloud"),
+        pytest.lazy_fixture("s3"),
+        pytest.lazy_fixture("gs"),
+        pytest.lazy_fixture("hdfs"),
+    ],
+    indirect=True,
+)
+def test_update_import_url_to_remote_directory(
+    tmp_dir, dvc, workspace, local_remote
+):
+    workspace.gen({"data": {"foo": "foo", "bar": {"baz": "baz"}}})
+    stage = dvc.imp_url("remote://workspace/data", to_remote=True)
+
+    workspace.gen({"data": {"foo2": "foo2", "bar": {"baz2": "baz2"}}})
+    stage = dvc.update(stage.path, to_remote=True)
+
+    dvc.pull("data")
+    assert (tmp_dir / "data").read_text() == {
+        "foo": "foo",
+        "foo2": "foo2",
+        "bar": {"baz": "baz", "baz2": "baz2"},
+    }

tests/unit/command/test_update.py

@@ -13,5 +13,40 @@ def test_update(dvc, mocker):
     assert cmd.run() == 0
 
     m.assert_called_once_with(
-        targets=["target1", "target2"], rev="REV", recursive=True,
+        targets=["target1", "target2"],
+        rev="REV",
+        recursive=True,
+        to_remote=False,
+        remote=None,
+        jobs=None,
+    )
+
+
+def test_update_to_remote(dvc, mocker):
+    cli_args = parse_args(
+        [
+            "update",
+            "target1",
+            "target2",
+            "--to-remote",
+            "-j",
+            "5",
+            "-r",
+            "remote",
+            "--recursive",
+        ]
+    )
+    assert cli_args.func == CmdUpdate
+    cmd = cli_args.func(cli_args)
+    m = mocker.patch("dvc.repo.Repo.update")
+
+    assert cmd.run() == 0
+
+    m.assert_called_once_with(
+        targets=["target1", "target2"],
+        rev=None,
+        recursive=True,
+        to_remote=True,
+        remote="remote",
+        jobs=5,
     )