roll-to-release

gonzo/tasks/release.py

@@ -5,6 +5,7 @@
 from fabric.api import task, env, sudo, put, run, local, settings
 from fabric.context_managers import prefix as fab_prefix, hide
 from fabric.contrib.files import exists
+from fabric.utils import abort
 
 from gonzo.config import PROJECT_ROOT, local_state
 from gonzo.utils import last_index
@@ -352,8 +353,15 @@ def purge_release(release):
 
 
 @task
-def rollback():
-    """ Roll back to the most recent active release in the history file.
+def rollback(release=None):
+    """ Either roll back to the most recent active release in the history file
+        or to the specified release.
+
+        Specifying a ``release`` SHA will roll back to the given release
+        provided it is in the history list and purge all subsequent releases so
+        that it is the most current. Providing a partial SHA or other ref will
+        use ``git rev-parse`` to expand the full SHA so that it can be looked
+        up in the history list.
 
         This is used for quick recovery in case of bugs discovered shortly
         after activating a new release.
@@ -362,16 +370,22 @@ def rollback():
         code should be restarted following this command.
     """
 
-    current_release = get_current()
+    if release:
+        # Attempt to roll back to the specified release
+        release = rev_parse(release)
+        if release not in list_releases():
+            abort('release ({}) not found in release list'.format(release))
 
-    previous_release = get_previous_release(current_release)
+    else:
+        current_release = get_current()
+        release = get_previous_release(current_release)
 
-    if not previous_release:
-        raise RuntimeError("No release to roll back to")
+        if not release:
+            abort("No release to roll back to")
 
     # sadly, there's not way to make this atomic
-    set_current(previous_release)
-    rollback_history(previous_release)
+    set_current(release)
+    rollback_history(release)
 
 
 @task

tests/test_release.py

@@ -116,17 +116,54 @@ def test_rollback(get_current, set_current):
     assert_called_once_with(set_current, 'aaa')
 
 
+@patch('gonzo.tasks.release.abort')
 @patch('gonzo.tasks.release.set_current')
 @patch('gonzo.tasks.release.get_current')
-def test_rollback_nowhere_to_go(get_current, set_current):
+def test_rollback_nowhere_to_go(get_current, set_current, abort):
     get_current.return_value = 'aaa'
+    abort.side_effect = ValueError
     with mock_history(initial=['aaa']) as releases:
-        with pytest.raises(RuntimeError):
+        with pytest.raises(ValueError):
             rollback()
+        assert abort.called is True
         assert releases == ['aaa']
     assert_has_calls(set_current, [])
 
 
+@patch('gonzo.tasks.release.abort')
+@patch('gonzo.tasks.release.set_current')
+@patch('gonzo.tasks.release.rev_parse')
+def test_rollback_to_invalid_release(rev_parse, set_current, abort):
+    rev_parse.return_value = 'bbb'
+    abort.side_effect = ValueError
+    with mock_history(initial=['aaa']) as releases:
+        with pytest.raises(ValueError):
+            rollback('bbb')
+        assert abort.called is True
+        assert releases == ['aaa']
+    assert_has_calls(set_current, [])
+
+
+@patch('gonzo.tasks.release.set_current')
+@patch('gonzo.tasks.release.rev_parse')
+def test_rollback_to_previous_release(rev_parse, set_current):
+    rev_parse.return_value = 'aaa'
+    with mock_history(initial=['aaa', 'bbb']) as releases:
+        rollback('aaa')
+        assert releases == ['aaa']
+    assert_called_once_with(set_current, 'aaa')
+
+
+@patch('gonzo.tasks.release.set_current')
+@patch('gonzo.tasks.release.rev_parse')
+def test_rollback_to_release(rev_parse, set_current):
+    rev_parse.return_value = 'aaa'
+    with mock_history(initial=['aaa', 'bbb', 'ccc']) as releases:
+        rollback('aaa')
+        assert releases == ['aaa']
+    assert_called_once_with(set_current, 'aaa')
+
+
 @patch('gonzo.tasks.release.get_commit')
 @patch('gonzo.tasks.release.set_current')
 @patch('gonzo.tasks.release.get_current')