Move solar lib to root directory

solar/events/api.py

@@ -0,0 +1,155 @@
+#    Copyright 2015 Mirantis, Inc.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+
+__all__ = ['add_dep', 'add_react', 'Dep', 'React', 'add_event']
+
+import networkx as nx
+
+from solar.core.log import log
+from solar.events.controls import Dep, React, StateChange
+
+from solar.dblayer.solar_models import Resource
+
+def create_event(event_dict):
+    etype = event_dict['etype']
+    kwargs = {'child': event_dict['child'],
+              'parent': event_dict['parent'],
+              'child_action': event_dict['child_action'],
+              'parent_action': event_dict['parent_action'],
+              'state': event_dict['state']}
+    if etype == React.etype:
+        return React(**kwargs)
+    elif etype == Dep.etype:
+        return Dep(**kwargs)
+    else:
+        raise Exception('No support for type %s', etype)
+
+
+def add_default_events(emitter, receiver):
+    events_to_add = [
+        Dep(emitter.name, 'run', 'success', receiver.name, 'run'),
+        Dep(emitter.name, 'update', 'success', receiver.name, 'update'),
+        Dep(receiver.name, 'remove', 'success', emitter.name, 'remove')
+    ]
+    add_events(emitter.name, events_to_add)
+
+
+def add_event(ev):
+    rst = all_events(ev.parent)
+    for rev in rst:
+        if ev == rev:
+            break
+    else:
+        add_events(ev.parent, [ev])
+
+
+def add_dep(parent, dep, actions, state='success'):
+    for act in actions:
+        d = Dep(parent, act, state=state,
+                child=dep, child_action=act)
+        add_event(d)
+        log.debug('Added event: %s', d)
+
+
+def add_react(parent, dep, actions, state='success'):
+    for act in actions:
+        r = React(parent, act, state=state,
+                  child=dep, child_action=act)
+        add_event(r)
+        log.debug('Added event: %s', r)
+
+
+def add_events(resource, lst):
+    resource = Resource.get(resource)
+    events = resource.events
+    # TODO: currently we don't track mutable objects
+    events.extend([ev.to_dict() for ev in lst])
+    resource.events = events
+    # import pdb; pdb.settrace()
+    resource.save_lazy()
+
+
+def remove_event(ev):
+    to_remove = ev.to_dict()
+    resource = ev.parent
+    resource = Resource.get(resource)
+    # TODO: currently we don't track mutable objects
+    events = resource.events
+    events.remove(to_remove)
+    resource.events = events
+    resource.save_lazy()
+
+
+def all_events(resource):
+    return [create_event(e) for e in Resource.get(resource).events]
+
+
+def bft_events_graph(start):
+    """Builds graph of events traversing events in breadth-first order
+    This graph doesnt necessary reflect deployment order, it is used
+    to show dependencies between resources
+    """
+    dg = nx.DiGraph()
+    stack = [start]
+    visited = set()
+
+    while stack:
+        item = stack.pop()
+        current_events = all_events(item)
+
+        for ev in current_events:
+            dg.add_edge(ev.parent_node, ev.child_node, label=ev.state)
+
+            if ev.child in visited:
+                continue
+
+            # it is possible to have events leading to same resource but
+            # different action
+            if ev.child in stack:
+                continue
+
+            stack.append(ev.child)
+        visited.add(ev.parent)
+    return dg
+
+
+
+def build_edges(changes_graph, events):
+    """
+    :param changes_graph: nx.DiGraph object with actions to be executed
+    :param events: {res: [controls.Event objects]}
+    """
+    events_graph = nx.MultiDiGraph()
+
+    for res_evts in events.values():
+        for ev in res_evts:
+            events_graph.add_edge(ev.parent_node, ev.child_node, event=ev)
+
+    stack = changes_graph.nodes()
+    visited = set()
+    while stack:
+        event_name = stack.pop(0)
+
+        if event_name in events_graph:
+            log.debug('Next events after %s are %s', event_name, events_graph.successors(event_name))
+        else:
+            log.debug('No outgoing events based on %s', event_name)
+
+        if event_name not in visited:
+            for parent, child, data in events_graph.edges(event_name, data=True):
+                succ_ev = data['event']
+                succ_ev.insert(stack, changes_graph)
+        visited.add(event_name)
+    return changes_graph