Patch/update schema juju 2.3 alpha1 (#142)

[osm/N2VC.git] / juju / model.py

diff --git a/juju/model.py b/juju/model.py
index e56ad66..160707b 100644 (file)
--- a/juju/model.py
+++ b/juju/model.py
@@ -76,6 +76,9 @@ class _Observer(object):
 
 
 class ModelObserver(object):
+    """
+    Base class for creating observers that react to changes in a model.
+    """
     async def __call__(self, delta, old, new, model):
         handler_name = 'on_{}_{}'.format(delta.entity, delta.type)
         method = getattr(self, handler_name, self.on_change)
@@ -84,6 +87,8 @@ class ModelObserver(object):
     async def on_change(self, delta, old, new, model):
         """Generic model-change handler.
 
+        This should be overridden in a subclass.
+
         :param delta: :class:`juju.client.overrides.Delta`
         :param old: :class:`juju.model.ModelEntity`
         :param new: :class:`juju.model.ModelEntity`
@@ -374,6 +379,9 @@ class ModelEntity(object):
 
 
 class Model(object):
+    """
+    The main API for interacting with a Juju model.
+    """
     def __init__(self, loop=None):
         """Instantiate a new connected Model.
 
@@ -390,6 +398,16 @@ class Model(object):
         self._watch_received = asyncio.Event(loop=self.loop)
         self._charmstore = CharmStore(self.loop)
 
+    async def __aenter__(self):
+        await self.connect_current()
+        return self
+
+    async def __aexit__(self, exc_type, exc, tb):
+        await self.disconnect()
+
+        if exc_type is not None:
+            return False
+
     async def connect(self, *args, **kw):
         """Connect to an arbitrary Juju model.
 
@@ -745,14 +763,34 @@ class Model(object):
                 'zone=us-east-1a' - starts a machine in zone us-east-1s on AWS
                 'maas2.name' - acquire machine maas2.name on MAAS
 
-        :param dict constraints: Machine constraints
+        :param dict constraints: Machine constraints, which can contain the
+            the following keys::
+
+                arch : str
+                container : str
+                cores : int
+                cpu_power : int
+                instance_type : str
+                mem : int
+                root_disk : int
+                spaces : list(str)
+                tags : list(str)
+                virt_type : str
+
             Example::
 
                 constraints={
                     'mem': 256 * MB,
+                    'tags': ['virtual'],
                 }
 
-        :param list disks: List of disk constraint dictionaries
+        :param list disks: List of disk constraint dictionaries, which can
+            contain the following keys::
+
+                count : int
+                pool : str
+                size : int
+
             Example::
 
                 disks=[{
@@ -1860,6 +1898,12 @@ class CharmStore(object):
 
 
 class CharmArchiveGenerator(object):
+    """
+    Create a Zip archive of a local charm directory for upload to a controller.
+
+    This is used automatically by
+    `Model.add_local_charm_dir <#juju.model.Model.add_local_charm_dir>`_.
+    """
     def __init__(self, path):
         self.path = os.path.abspath(os.path.expanduser(path))