Add get_config() and get_constraints() for Application

[osm/N2VC.git] / examples / relate.py

diff --git a/examples/relate.py b/examples/relate.py
index 967a785..8e42bab 100644 (file)
--- a/examples/relate.py
+++ b/examples/relate.py
@@ -1,5 +1,10 @@
 """
-Deploy two charms and relate them.
+This example:
+
+1. Connects to the current model
+2. Resets it
+3. Deploys two charms and relates them
+4. Waits for units to be idle, then exits
 
 """
 import asyncio
@@ -8,46 +13,86 @@ import logging
 from juju.model import Model, ModelObserver
 
 
+class MyRemoveObserver(ModelObserver):
+    async def on_change(self, delta, old, new, model):
+        if delta.type == 'remove':
+            assert(new.latest() == new)
+            assert(new.next() is None)
+            assert(new.dead)
+            assert(new.current)
+            assert(new.connected)
+            assert(new.previous().dead)
+            assert(not new.previous().current)
+            assert(not new.previous().connected)
+
+
 class MyModelObserver(ModelObserver):
-    def on_change(self, delta, old, new, model):
-        if model.all_units_idle():
+    _shutting_down = False
+
+    async def on_change(self, delta, old, new, model):
+        if model.units and model.all_units_idle() and not self._shutting_down:
+            self._shutting_down = True
             logging.debug('All units idle, disconnecting')
-            task = model.loop.create_task(model.disconnect())
-            task.add_done_callback(lambda fut: model.loop.stop())
+            await model.reset(force=True)
+            await model.disconnect()
+            model.loop.stop()
 
 
 async def run():
     model = Model()
     await model.connect_current()
 
+    model.add_observer(MyRemoveObserver())
     await model.reset(force=True)
-    await model.block_until(
-        lambda: len(model.machines) == 0
-    )
     model.add_observer(MyModelObserver())
 
-    await model.deploy(
-        'ubuntu-0',
+    ubuntu_app = await model.deploy(
+        'ubuntu',
         service_name='ubuntu',
         series='trusty',
         channel='stable',
     )
+    ubuntu_app.on_change(asyncio.coroutine(
+        lambda delta, old_app, new_app, model:
+            print('App changed: {}'.format(new_app.entity_id))
+    ))
+    ubuntu_app.on_remove(asyncio.coroutine(
+        lambda delta, old_app, new_app, model:
+            print('App removed: {}'.format(old_app.entity_id))
+    ))
+    ubuntu_app.on_unit_add(asyncio.coroutine(
+        lambda delta, old_unit, new_unit, model:
+            print('Unit added: {}'.format(new_unit.entity_id))
+    ))
+    ubuntu_app.on_unit_remove(asyncio.coroutine(
+        lambda delta, old_unit, new_unit, model:
+            print('Unit removed: {}'.format(old_unit.entity_id))
+    ))
+    unit_a, unit_b = await ubuntu_app.add_units(count=2)
+    unit_a.on_change(asyncio.coroutine(
+        lambda delta, old_unit, new_unit, model:
+            print('Unit changed: {}'.format(new_unit.entity_id))
+    ))
     await model.deploy(
-        'nrpe-11',
+        'nrpe',
         service_name='nrpe',
         series='trusty',
         channel='stable',
-        num_units=0,
+        num_units=1,
     )
-    await model.add_relation(
+    my_relation = await model.add_relation(
         'ubuntu',
         'nrpe',
     )
-
+    my_relation.on_remove(asyncio.coroutine(
+        lambda delta, old_rel, new_rel, model:
+            print('Relation removed: {}'.format(old_rel.endpoints))
+    ))
 
 logging.basicConfig(level=logging.DEBUG)
 ws_logger = logging.getLogger('websockets.protocol')
 ws_logger.setLevel(logging.INFO)
 loop = asyncio.get_event_loop()
+loop.set_debug(True)
 loop.create_task(run())
 loop.run_forever()