Provide helper to evac current unit

.pydevproject

@@ -1,10 +1,9 @@
 <?xml version="1.0" encoding="UTF-8" standalone="no"?>
-<?eclipse-pydev version="1.0"?>
-
-<pydev_project>
+<?eclipse-pydev version="1.0"?><pydev_project>
 <pydev_property name="org.python.pydev.PYTHON_PROJECT_VERSION">python 2.7</pydev_property>
 <pydev_property name="org.python.pydev.PYTHON_PROJECT_INTERPRETER">Default</pydev_property>
 <pydev_pathproperty name="org.python.pydev.PROJECT_SOURCE_PATH">
 <path>/quantum-gateway/hooks</path>
+<path>/quantum-gateway/templates</path>
 </pydev_pathproperty>
 </pydev_project>

hooks/hooks.py

@@ -143,6 +143,13 @@ def render_metadata_api_conf():
                        )
 
 
+def render_evacuate_unit():
+    context = get_keystone_conf()
+    if context:
+        with open('/usr/local/bin/quantum-evacuate-unit', "w") as conf:
+            conf.write(utils.render_template('evacuate_unit.py', context))
+
+
 def get_keystone_conf():
     for relid in utils.relation_ids('quantum-network-service'):
         for unit in utils.relation_list(relid):
@@ -256,6 +263,7 @@ def nm_changed():
     render_l3_agent_conf()
     render_metadata_agent_conf()
     render_metadata_api_conf()
+    render_evacuate_unit()
     store_ca_cert()
 
 

templates/evacuate_unit.py

@@ -0,0 +1,71 @@
+#!/usr/bin/python
+
+import subprocess
+
+
+def log(priority, message):
+    print "{}: {}".format(priority, message)
+
+DHCP_AGENT = "DHCP Agent"
+L3_AGENT = "L3 Agent"
+
+
+def evacuate_unit(unit):
+    ''' Use agent scheduler API to detect down agents and re-schedule '''
+    from quantumclient.v2_0 import client
+    # TODO: Fixup for https keystone
+    auth_url = 'http://{{ keystone_host }}:{{ auth_port }}/v2.0'
+    quantum = client.Client(username='{{ service_username }}',
+                            password='{{ service_password }}',
+                            tenant_name='{{ service_tenant }}',
+                            auth_url=auth_url,
+                            region_name='{{ region }}')
+
+    agents = quantum.list_agents(agent_type=DHCP_AGENT)
+    dhcp_agents = []
+    l3_agents = []
+    networks = {}
+    for agent in agents['agents']:
+        if agent['alive'] and agent['host'] != unit:
+            dhcp_agents.append(agent['id'])
+        elif agent['host'] == unit:
+            log('INFO', 'DHCP Agent %s down' % agent['id'])
+            for network in \
+                quantum.list_networks_on_dhcp_agent(agent['id'])['networks']:
+                networks[network['id']] = agent['id']
+
+    agents = quantum.list_agents(agent_type=L3_AGENT)
+    routers = {}
+    for agent in agents['agents']:
+        if agent['alive'] and agent['host'] != unit:
+            l3_agents.append(agent['id'])
+        elif agent['host'] == unit:
+            for router in \
+                quantum.list_routers_on_l3_agent(agent['id'])['routers']:
+                routers[router['id']] = agent['id']
+
+    index = 0
+    for router_id in routers:
+        agent = index % len(l3_agents)
+        log('INFO',
+            'Moving router %s from %s to %s' % \
+            (router_id, routers[router_id], l3_agents[agent]))
+        quantum.remove_router_from_l3_agent(l3_agent=routers[router_id],
+                                            router_id=router_id)
+        quantum.add_router_to_l3_agent(l3_agent=l3_agents[agent],
+                                       body={'router_id': router_id})
+        index += 1
+
+    index = 0
+    for network_id in networks:
+        agent = index % len(dhcp_agents)
+        log('INFO',
+            'Moving network %s from %s to %s' % \
+            (network_id, networks[network_id], dhcp_agents[agent]))
+        quantum.remove_network_from_dhcp_agent(dhcp_agent=networks[network_id],
+                                               network_id=network_id)
+        quantum.add_network_to_dhcp_agent(dhcp_agent=dhcp_agents[agent],
+                                          body={'network_id': network_id})
+        index += 1
+
+evacuate_unit(subprocess.check_call(['hostname', '-f']))