Containers have names which are used to isolate them to their service

plum/service.py

@@ -14,7 +14,7 @@ class Service(object):
 
     @property
     def containers(self):
-        return self.client.containers()
+        return [c for c in self.client.containers() if parse_name(get_container_name(c))[0] == self.name]
 
     def start(self):
         if len(self.containers) == 0:
@@ -31,8 +31,37 @@ class Service(object):
             self.stop_container()
 
     def start_container(self):
-        container = self.client.create_container(self.image, self.command)
+        number = self.next_container_number()
+        name = make_name(self.name, number)
+        container = self.client.create_container(self.image, self.command, name=name)
         self.client.start(container['Id'])
 
     def stop_container(self):
         self.client.kill(self.containers[0]['Id'])
+
+    def next_container_number(self):
+        numbers = [parse_name(get_container_name(c))[1] for c in self.containers]
+
+        if len(numbers) == 0:
+            return 1
+        else:
+            return max(numbers) + 1
+
+
+def make_name(prefix, number):
+    return '%s_%s' % (prefix, number)
+
+
+def parse_name(name):
+    match = re.match('^(.+)_(\d+)$', name)
+
+    if match is None:
+        raise ValueError("Invalid name: %s" % name)
+
+    (service_name, suffix) = match.groups()
+
+    return (service_name, int(suffix))
+
+
+def get_container_name(container):
+    return container['Names'][0][1:]

plum/tests/service_test.py

@@ -39,6 +39,22 @@ class NameTestCase(ServiceTestCase):
         Service('_____')
 
 
+class ContainersTestCase(ServiceTestCase):
+    def test_containers(self):
+        foo = self.create_service('foo')
+        bar = self.create_service('bar')
+
+        foo.start()
+
+        self.assertEqual(len(foo.containers), 1)
+        self.assertEqual(len(bar.containers), 0)
+
+        bar.scale(2)
+
+        self.assertEqual(len(foo.containers), 1)
+        self.assertEqual(len(bar.containers), 2)
+
+
 class ScalingTestCase(ServiceTestCase):
     def setUp(self):
         super(ServiceTestCase, self).setUp()