From d54e6799cee1ba79a92c39ee3663cdafbd0442d5 Mon Sep 17 00:00:00 2001
From: Clark Boylan <clark.boylan@gmail.com>
Date: Thu, 20 Sep 2018 13:43:17 -0700
Subject: [PATCH] Manage the debian interface header in one place

We were setting an identical header for all of the different interface
types. Manage this in a single location which simplifies the control
flow through the different interface types.

Change-Id: Ib0300d46896cf95c83223f1af3e2fe890698af2b
---
 glean/cmd.py | 36 +++++++++++++-----------------------
 1 file changed, 13 insertions(+), 23 deletions(-)

diff --git a/glean/cmd.py b/glean/cmd.py
index 26c0ae4..4ec01cb 100644
--- a/glean/cmd.py
+++ b/glean/cmd.py
@@ -820,11 +820,16 @@ def write_debian_interfaces(interfaces, sys_interfaces):
         if os.path.exists(iface_path):
             continue
 
-        iface_path = os.path.join(eni_d_path, '%s.cfg' % interface_name)
+        if iface_path not in files_to_write:
+            # Write the header if this is the first time editing
+            # this interface.
+            result = "auto {0}\n".format(interface_name)
+        else:
+            # Append to existing config
+            result = files_to_write[iface_path]
 
         if interface['type'] == 'ipv4_dhcp':
-            header = "auto {0}\n".format(interface_name)
-            result = "iface {0} inet dhcp\n".format(interface_name)
+            result += "iface {0} inet dhcp\n".format(interface_name)
             if vlan_raw_device is not None:
                 result += "    vlan-raw-device {0}\n".format(vlan_raw_device)
                 result += "    hw-mac-address {0}\n".format(
@@ -833,16 +838,11 @@ def write_debian_interfaces(interfaces, sys_interfaces):
                 result += _write_debian_bond_conf(interface_name,
                                                   interface,
                                                   sys_interfaces)
-            if iface_path in files_to_write:
-                # There are more than one address for this interface
-                files_to_write[iface_path] += result
-            else:
-                files_to_write[iface_path] = header + result
+            files_to_write[iface_path] = result
             continue
 
         if interface['type'] == 'manual':
-            header = "auto {0}\n".format(interface_name)
-            result = "iface {0} inet manual\n".format(interface_name)
+            result += "iface {0} inet manual\n".format(interface_name)
             if 'bond_master' in interface:
                 result += "    bond-master {0}\n".format(
                     interface['bond_master'])
@@ -850,11 +850,7 @@ def write_debian_interfaces(interfaces, sys_interfaces):
                 result += _write_debian_bond_conf(interface_name,
                                                   interface,
                                                   sys_interfaces)
-            if iface_path in files_to_write:
-                # There are more than one address for this interface
-                files_to_write[iface_path] += result
-            else:
-                files_to_write[iface_path] = header + result
+            files_to_write[iface_path] = result
             continue
 
         if interface['type'] == 'ipv6':
@@ -868,8 +864,7 @@ def write_debian_interfaces(interfaces, sys_interfaces):
         if not link_type:
             continue
 
-        header = "auto {0}\n".format(interface_name)
-        result = "iface {name} {link_type} static\n".format(
+        result += "iface {name} {link_type} static\n".format(
             name=interface_name, link_type=link_type)
         if vlan_raw_device:
             result += "    vlan-raw-device {0}\n".format(vlan_raw_device)
@@ -914,12 +909,7 @@ def write_debian_interfaces(interfaces, sys_interfaces):
                 result += route_del.format(
                     net=route['network'], mask=_netmask, gw=route['gateway'],
                     interface=interface_name)
-
-        if iface_path in files_to_write:
-            # There are more than one address for this interface
-            files_to_write[iface_path] += result
-        else:
-            files_to_write[iface_path] = header + result
+        files_to_write[iface_path] = result
 
     # Configure any interfaces not mentioned in the config drive data for DHCP.
     for mac, iname in sorted(