Added code for configurable multiple gateway interfaces.

README.md

@@ -36,7 +36,7 @@ This is an early access version of the PLUMgrid Gateway charm and it is not mean
 Example Config
 
     plumgrid-gateway:
-        external-interface: eth1
+        external-interfaces: '{"node01":"eth5,eth2","node02":"eth4,eth8"}'
         install_sources: 'ppa:plumgrid-team/stable'
         install_keys: 'null'
     plumgrid-edge:
@@ -54,7 +54,7 @@ Example Config
         neutron-plugin: "plumgrid"
         plumgrid-virtual-ip: "192.168.100.250"
 
-The "external-interface" config parameter should be the interface that will provide external connectivity. 
+The "external-interfaces" config parameter should be the interfaces that will provide external connectivity on each of the gateway nodes. Should be provided as a json in a string with hostname and interface names.
 Provide the source repo path for PLUMgrid Debs in 'install_sources' and the corresponding keys in 'install_keys'.
 The virtual IP passed on in the neutron-api charm has to be same as the one passed in the plumgrid-director charm.
 

config.yaml

@@ -1,8 +1,10 @@
 options:
-  external-interface:
-    default: eth1
+  external-interfaces:
+    default: '{"hostname":"eth1,eth2"}'
     type: string
-    description: The interface that will provide external connectivity
+    description: |
+       One or multiple interfaces that will provide external connectivity on
+       each of the gateway nodes. Provided in form of json in a string.
   lcm-ssh-key:
     default: 'null'
     type: string

hooks/pg_gw_context.py

@@ -7,7 +7,6 @@ from charmhelpers.core.hookenv import (
     relation_ids,
     related_units,
     relation_get,
-    config,
 )
 from charmhelpers.contrib.openstack import context
 
@@ -60,7 +59,6 @@ class PGGwContext(context.NeutronContext):
         if not pg_ctxt:
             return {}
 
-        conf = config()
         pg_dir_ips = ''
         pg_dir_settings = _pg_dir_settings()
         single_ip = True
@@ -73,12 +71,10 @@ class PGGwContext(context.NeutronContext):
         pg_ctxt['local_ip'] = pg_dir_ips
         unit_hostname = get_unit_hostname()
         pg_ctxt['pg_hostname'] = unit_hostname
-        from pg_gw_utils import check_interface_type
-        interface_type = check_interface_type()
-        pg_ctxt['interface'] = interface_type
+        from pg_gw_utils import check_interface_type, get_gw_interfaces
+        pg_ctxt['interface'] = check_interface_type()
         pg_ctxt['label'] = unit_hostname
         pg_ctxt['fabric_mode'] = 'host'
-
-        pg_ctxt['ext_interface'] = conf['external-interface']
+        pg_ctxt['ext_interfaces'] = get_gw_interfaces()
 
         return pg_ctxt

hooks/pg_gw_utils.py

@@ -20,11 +20,13 @@ from collections import OrderedDict
 from charmhelpers.contrib.openstack.utils import (
     os_release,
 )
+from socket import gethostname as get_unit_hostname
 import pg_gw_context
 import subprocess
 import time
 import os
 import re
+import json
 
 LXC_CONF = "/etc/libvirt/lxc.conf"
 TEMPLATES = 'templates/'
@@ -35,6 +37,7 @@ PG_HN_CONF = '%s/conf/etc/hostname' % PG_LXC_DATA_PATH
 PG_HS_CONF = '%s/conf/etc/hosts' % PG_LXC_DATA_PATH
 PG_IFCS_CONF = '%s/conf/pg/ifcs.conf' % PG_LXC_DATA_PATH
 AUTH_KEY_PATH = '%s/root/.ssh/authorized_keys' % PG_LXC_DATA_PATH
+IFC_LIST_GW = '/var/run/plumgrid/lxc/ifc_list_gateway'
 
 SUDOERS_CONF = '/etc/sudoers.d/ifc_ctl_sudoers'
 
@@ -103,6 +106,7 @@ def ensure_files():
     write_file(SUDOERS_CONF,
                "\nnova ALL=(root) NOPASSWD: /opt/pg/bin/ifc_ctl_pp *\n",
                owner='root', group='root', perms=0o644)
+    _exec_cmd(cmd=['rm', '-f', IFC_LIST_GW])
 
 
 def restart_pg():
@@ -155,6 +159,23 @@ def check_interface_type():
         return default_interface
 
 
+def get_gw_interfaces():
+    '''
+    Gateway node can have multiple interfaces. This function parses json
+    provided in config to get all gateway interfaces for this node.
+    '''
+    node_interfaces = ['eth1']
+    try:
+        all_interfaces = json.loads(config('external-interfaces'))
+    except ValueError:
+        log("Invalid JSON")
+        return node_interfaces
+    hostname = get_unit_hostname()
+    if hostname in all_interfaces:
+        node_interfaces = all_interfaces[hostname].split(',')
+    return node_interfaces
+
+
 def ensure_mtu():
     '''
     Ensures required MTU of the underlying networking of the node.

templates/kilo/ifcs.conf

@@ -1,6 +1,7 @@
 {{ interface }} = fabric_core host
-{% if ext_interface -%}
-{{ ext_interface }} = access_phys
-
+{% if ext_interfaces -%}
+{% for ip in ext_interfaces -%}
+{{ ip }} = access_phys
+{% endfor -%}
 {% endif -%}
 

unit_tests/test_pg_gw_context.py

@@ -5,7 +5,6 @@ import pg_gw_utils as utils
 import charmhelpers
 
 TO_PATCH = [
-    'config',
     'get_unit_hostname',
 ]
 
@@ -22,8 +21,6 @@ class PGGwContextTest(CharmTestCase):
 
     def setUp(self):
         super(PGGwContextTest, self).setUp(context, TO_PATCH)
-        self.config.side_effect = self.test_config.get
-        self.test_config.set('external-interface', 'eth1')
 
     def tearDown(self):
         super(PGGwContextTest, self).tearDown()
@@ -41,7 +38,9 @@ class PGGwContextTest(CharmTestCase):
     @patch.object(charmhelpers.contrib.openstack.context,
                   'neutron_plugin_attribute')
     @patch.object(utils, 'check_interface_type')
-    def test_neutroncc_context_api_rel(self, _int_type, _npa, _pg_dir_settings,
+    @patch.object(utils, 'get_gw_interfaces')
+    def test_neutroncc_context_api_rel(self, _gw_int, _int_type,
+                                       _npa, _pg_dir_settings,
                                        _save_flag_file, _config_flag,
                                        _unit_get, _unit_priv_ip, _config,
                                        _is_clus, _https, _ens_pkgs):
@@ -50,16 +49,8 @@ class PGGwContextTest(CharmTestCase):
                 return "neutron.randomdriver"
             if section == "config":
                 return "neutron.randomconfig"
-        config = {'external-interface': "eth1"}
-
-        def mock_config(key=None):
-            if key:
-                return config.get(key)
-
-            return config
 
         self.maxDiff = None
-        self.config.side_effect = mock_config
         _npa.side_effect = mock_npa
         _unit_get.return_value = '192.168.100.201'
         _unit_priv_ip.return_value = '192.168.100.201'
@@ -68,9 +59,10 @@ class PGGwContextTest(CharmTestCase):
         _config_flag.return_value = False
         _pg_dir_settings.return_value = {'pg_dir_ip': '192.168.100.201'}
         _int_type.return_value = 'juju-br0'
+        _gw_int.return_value = ['eth1']
         napi_ctxt = context.PGGwContext()
         expect = {
-            'ext_interface': "eth1",
+            'ext_interfaces': ['eth1'],
             'config': 'neutron.randomconfig',
             'core_plugin': 'neutron.randomdriver',
             'local_ip': 'pg_dir_ip',