T1470: improve output of "show dhcpv6 server leases"

- change DUID to IAID_DUID
- format IAID_DUID as colon-separated hex list
- implement functions: pool, sort, state
- add op-mode definitions for pool, sort, state
- add columns: State, Type, Last communication, Pool
- implement json output
- implement completionHelp function

3 files changed, 120 insertions, 16 deletions

diff --git a/op-mode-definitions/dhcp.xml b/op-mode-definitions/dhcp.xml
index 85403af6f..989c8274a 100644
--- a/op-mode-definitions/dhcp.xml
+++ b/op-mode-definitions/dhcp.xml
@@ -59,6 +59,35 @@
                   <help>Show DHCPv6 server leases</help>
                 </properties>
                 <command>sudo ${vyos_op_scripts_dir}/show_dhcpv6.py --leases</command>
+                <children>
+                  <tagNode name="pool">
+                    <properties>
+                      <help>Show DHCPv6 server leases for a specific pool</help>
+                      <completionHelp>
+                        <script>sudo ${vyos_op_scripts_dir}/show_dhcpv6.py --allowed pool</script>
+                      </completionHelp>
+                    </properties>
+                    <command>sudo ${vyos_op_scripts_dir}/show_dhcpv6.py --leases --pool $6</command>
+                  </tagNode>
+                  <tagNode name="sort">
+                    <properties>
+                      <help>Show DHCPv6 server leases sorted by the specified key</help>
+                      <completionHelp>
+                        <script>sudo ${vyos_op_scripts_dir}/show_dhcpv6.py --allowed sort</script>
+                      </completionHelp>
+                    </properties>
+                    <command>sudo ${vyos_op_scripts_dir}/show_dhcpv6.py --leases --sort $6</command>
+                  </tagNode>
+                  <tagNode name="state">
+                    <properties>
+                      <help>Show DHCPv6 server leases with a specific state</help>
+                      <completionHelp>
+                        <script>sudo ${vyos_op_scripts_dir}/show_dhcpv6.py --allowed state</script>
+                      </completionHelp>
+                    </properties>
+                    <command>sudo ${vyos_op_scripts_dir}/show_dhcpv6.py --leases --state $6</command>
+                  </tagNode>
+                </children>
               </node>
             </children>
           </node>
diff --git a/src/conf_mode/dhcpv6_server.py b/src/conf_mode/dhcpv6_server.py
index 37da3ef25..f5117de53 100755
--- a/src/conf_mode/dhcpv6_server.py
+++ b/src/conf_mode/dhcpv6_server.py
@@ -101,6 +101,9 @@ shared-network {{ network.name }} {
         {%- endfor %}
     }
     {%- endfor %}
+    on commit {
+        set shared-networkname = "{{ network.name }}";
+    }
 }
 {%- endif %}
 {% endfor %}
diff --git a/src/op_mode/show_dhcpv6.py b/src/op_mode/show_dhcpv6.py
index bf73b92ea..f1f5a6a55 100755
--- a/src/op_mode/show_dhcpv6.py
+++ b/src/op_mode/show_dhcpv6.py
@@ -20,11 +20,42 @@ import argparse
 import ipaddress
 import tabulate
 import sys
+import collections
 
 from vyos.config import Config
 from isc_dhcp_leases import Lease, IscDhcpLeases
 
 lease_file = "/config/dhcpdv6.leases"
+pool_key = "shared-networkname"
+
+lease_display_fields = collections.OrderedDict()
+lease_display_fields['ip'] = 'IPv6 address'
+lease_display_fields['state'] = 'State'
+lease_display_fields['last_comm'] = 'Last communication'
+lease_display_fields['expires'] = 'Lease expiration'
+lease_display_fields['type'] = 'Type'
+lease_display_fields['pool'] = 'Pool'
+lease_display_fields['iaid_duid'] = 'IAID_DUID'
+
+lease_valid_states = ['all', 'active', 'free', 'expired', 'released', 'abandoned', 'reset', 'backup']
+
+def in_pool(lease, pool):
+    if pool_key in lease.sets:
+        if lease.sets[pool_key] == pool:
+            return True
+
+    return False
+
+def format_hex_string(in_str):
+    out_str = ""
+
+    # if input is divisible by 2, add : every 2 chars
+    if len(in_str) > 0 and len(in_str) % 2 == 0:
+        out_str = ':'.join(a+b for a,b in zip(in_str[::2], in_str[1::2]))
+    else:
+        out_str = in_str
+
+    return out_str
 
 def get_lease_data(lease):
     data = {}
@@ -35,27 +66,55 @@ def get_lease_data(lease):
     except:
         data["expires"] = ""
 
-    data["duid"] = lease.host_identifier_string
+    try:
+        data["last_comm"] = lease.last_communication.strftime("%Y/%m/%d %H:%M:%S")
+    except:
+        data["last_comm"] = ""
+
+    # isc-dhcp records lease declarations as ia_{na|ta|pd} IAID_DUID {...}
+    # where IAID_DUID is the combined IAID and DUID
+    data["iaid_duid"] = format_hex_string(lease.host_identifier_string)
+
+    lease_types_long = {"na": "non-temporary", "ta": "temporary", "pd": "prefix delegation"}
+    data["type"] = lease_types_long[lease.type]
+
+    data["state"] = lease.binding_state
     data["ip"] = lease.ip
 
+    try:
+        data["pool"] = lease.sets[pool_key]
+    except:
+        data["pool"] = ""
+
     return data
 
-def get_leases(leases, state=None):
+def get_leases(leases, state, pool=None, sort='ip'):
     leases = IscDhcpLeases(lease_file).get()
 
-    if state is not None:
-        leases = list(filter(lambda x: x.binding_state == 'active', leases))
+    if state != 'all':
+        leases = list(filter(lambda x: x.binding_state == state, leases))
 
-    return list(map(get_lease_data, leases))
+    # filter lease by pool name
+    if pool is not None:
+        leases = list(filter(lambda x: in_pool(x, pool), leases))
 
-def show_leases(leases):
-    headers = ["IPv6 address", "Lease expiration", "DUID"]
+    leases = list(map(get_lease_data, leases))
+    if sort == 'ip':
+        leases = sorted(leases, key = lambda k: int(ipaddress.IPv6Address(k['ip'])))
+    else:
+        leases = sorted(leases, key = lambda k: k[sort])
+
+    return leases
 
+def show_leases(leases):
     lease_list = []
     for l in leases:
-        lease_list.append([l["ip"], l["expires"], l["duid"]])
+        lease_list_params = []
+        for k in lease_display_fields.keys():
+            lease_list_params.append(l[k])
+        lease_list.append(lease_list_params)
 
-    output = tabulate.tabulate(lease_list, headers)
+    output = tabulate.tabulate(lease_list, lease_display_fields.values())
 
     print(output)
 
@@ -63,11 +122,14 @@ if __name__ == '__main__':
     parser = argparse.ArgumentParser()
 
     group = parser.add_mutually_exclusive_group()
-    group.add_argument("-l", "--leases", action="store_true", help="Show DHCP leases")
-    group.add_argument("-s", "--statistics", action="store_true", help="Show DHCP statistics")
+    group.add_argument("-l", "--leases", action="store_true", help="Show DHCPv6 leases")
+    group.add_argument("-s", "--statistics", action="store_true", help="Show DHCPv6 statistics")
+    group.add_argument("--allowed", type=str, choices=["pool", "sort", "state"], help="Show allowed values for argument")
 
-    parser.add_argument("-p", "--pool", type=str, action="store", help="Show lease for specific pool")
-    parser.add_argument("-j", "--json", action="store_true", default=False, help="Product JSON output")
+    parser.add_argument("-p", "--pool", type=str, help="Show lease for specific pool")
+    parser.add_argument("-S", "--sort", type=str, choices=lease_display_fields.keys(), default='ip', help="Sort by")
+    parser.add_argument("-t", "--state", type=str, choices=lease_valid_states, default="active", help="Lease state to show")
+    parser.add_argument("-j", "--json", action="store_true", default=False, help="Produce JSON output")
 
     args = parser.parse_args()
 
@@ -78,9 +140,19 @@ if __name__ == '__main__':
         sys.exit(0)
 
     if args.leases:
-        leases = get_leases(lease_file, state='active')
-        show_leases(leases)
+        leases = get_leases(lease_file, args.state, args.pool, args.sort)
+
+        if args.json:
+            print(json.dumps(leases, indent=4))
+        else:
+            show_leases(leases)
     elif args.statistics:
         print("DHCPv6 statistics option is not available")
+    elif args.allowed == 'pool':
+        print(' '.join(c.list_effective_nodes("service dhcpv6-server shared-network-name")))
+    elif args.allowed == 'sort':
+        print(' '.join(lease_display_fields.keys()))
+    elif args.allowed == 'state':
+        print(' '.join(lease_valid_states))
     else:
-        print("Invalid option")
+        parser.print_help()