Narrow down except clause

To avoid masking brainfarts like the ones that led to
bug report below.

Related-bug: #1368835

Change-Id: I028b779e580da7719925a8e127f48bbe1aec211e

neutronclient/neutron/v2_0/agent.py

@@ -20,7 +20,7 @@ from neutronclient.neutron import v2_0 as neutronV20
 def _format_timestamp(component):
     try:
         return component['heartbeat_timestamp'].split(".", 2)[0]
-    except Exception:
+    except (TypeError, KeyError):
         return ''
 
 

neutronclient/neutron/v2_0/fw/firewallpolicy.py

@@ -30,7 +30,7 @@ def _format_firewall_rules(firewall_policy):
         output = '[' + ',\n '.join([rule for rule in
                                     firewall_policy['firewall_rules']]) + ']'
         return output
-    except Exception:
+    except (TypeError, KeyError):
         return ''
 
 

neutronclient/neutron/v2_0/network.py

@@ -25,7 +25,7 @@ def _format_subnets(network):
     try:
         return '\n'.join([' '.join([s['id'], s.get('cidr', '')])
                           for s in network['subnets']])
-    except Exception:
+    except (TypeError, KeyError):
         return ''
 
 

neutronclient/neutron/v2_0/port.py

@@ -26,7 +26,7 @@ from neutronclient.openstack.common import jsonutils
 def _format_fixed_ips(port):
     try:
         return '\n'.join([jsonutils.dumps(ip) for ip in port['fixed_ips']])
-    except Exception:
+    except (TypeError, KeyError):
         return ''
 
 

neutronclient/neutron/v2_0/router.py

@@ -27,7 +27,7 @@ from neutronclient.openstack.common import jsonutils
 def _format_external_gateway_info(router):
     try:
         return jsonutils.dumps(router['external_gateway_info'])
-    except Exception:
+    except (TypeError, KeyError):
         return ''
 
 

neutronclient/neutron/v2_0/subnet.py

@@ -27,7 +27,7 @@ def _format_allocation_pools(subnet):
     try:
         return '\n'.join([jsonutils.dumps(pool) for pool in
                           subnet['allocation_pools']])
-    except Exception:
+    except (TypeError, KeyError):
         return ''
 
 
@@ -35,7 +35,7 @@ def _format_dns_nameservers(subnet):
     try:
         return '\n'.join([jsonutils.dumps(server) for server in
                           subnet['dns_nameservers']])
-    except Exception:
+    except (TypeError, KeyError):
         return ''
 
 
@@ -43,7 +43,7 @@ def _format_host_routes(subnet):
     try:
         return '\n'.join([jsonutils.dumps(route) for route in
                           subnet['host_routes']])
-    except Exception:
+    except (TypeError, KeyError):
         return ''
 
 

neutronclient/neutron/v2_0/vpn/ipsec_site_connection.py

@@ -28,7 +28,7 @@ def _format_peer_cidrs(ipsec_site_connection):
     try:
         return '\n'.join([jsonutils.dumps(cidrs) for cidrs in
                           ipsec_site_connection['peer_cidrs']])
-    except Exception:
+    except (TypeError, KeyError):
         return ''