scripts: T4269: node.def generator should automatically add default values

Since introducing the XML <defaultValue> node it was common, but redundant,
practice to also add a help string indicating which value would be used as
default if the node is unset.

This makes no sense b/c it's duplicated code/value/characters and prone to
error. The node.def scripts should be extended to automatically render the
appropriate default value into the CLI help string.

For e.g. SSH the current PoC renders:

$ cat templates-cfg/service/ssh/port/node.def

multi:
type: txt
help: Port for SSH service (default: 22)
val_help: u32:1-65535; Numeric IP port
...
Not all subsystems are already migrated to get_config_dict() and make use of
the defaults() call - those subsystems need to be migrated, first before the new
default is added to the CLI help.

(cherry picked from commit a68c9238111c6caee78bb28f8054b8f0cfa0e374)

5 files changed, 7 insertions, 6 deletions

diff --git a/interface-definitions/include/accel-ppp/client-ipv6-pool.xml.i b/interface-definitions/include/accel-ppp/client-ipv6-pool.xml.i
index a692f2335..01cf0e040 100644
--- a/interface-definitions/include/accel-ppp/client-ipv6-pool.xml.i
+++ b/interface-definitions/include/accel-ppp/client-ipv6-pool.xml.i
@@ -21,7 +21,7 @@
               <help>Prefix length used for individual client</help>
               <valueHelp>
                 <format>u32:48-128</format>
-                <description>Client prefix length (default: 64)</description>
+                <description>Client prefix length</description>
               </valueHelp>
               <constraint>
                 <validator name="numeric" argument="--range 48-128"/>
diff --git a/interface-definitions/include/accel-ppp/radius-additions.xml.i b/interface-definitions/include/accel-ppp/radius-additions.xml.i
index 44ec64d7f..7adf294d1 100644
--- a/interface-definitions/include/accel-ppp/radius-additions.xml.i
+++ b/interface-definitions/include/accel-ppp/radius-additions.xml.i
@@ -21,7 +21,7 @@
             <help>Accounting port</help>
             <valueHelp>
               <format>u32:1-65535</format>
-              <description>Numeric IP port (default: 1813)</description>
+              <description>Numeric IP port</description>
             </valueHelp>
             <constraint>
               <validator name="numeric" argument="--range 1-65535"/>
@@ -130,7 +130,7 @@
         </leafNode>
         <leafNode name="port">
           <properties>
-            <help>Port for Dynamic Authorization Extension server (DM/CoA) (default: 1700)</help>
+            <help>Port for Dynamic Authorization Extension server (DM/CoA)</help>
             <valueHelp>
               <format>u32:1-65535</format>
               <description>TCP port</description>
diff --git a/interface-definitions/include/interface/ipv6-dup-addr-detect-transmits.xml.i b/interface-definitions/include/interface/ipv6-dup-addr-detect-transmits.xml.i
index babe6d20f..3b9294dd0 100644
--- a/interface-definitions/include/interface/ipv6-dup-addr-detect-transmits.xml.i
+++ b/interface-definitions/include/interface/ipv6-dup-addr-detect-transmits.xml.i
@@ -1,7 +1,7 @@
 <!-- include start from interface/ipv6-dup-addr-detect-transmits.xml.i -->
 <leafNode name="dup-addr-detect-transmits">
   <properties>
-    <help>Number of NS messages to send while performing DAD (default: 1)</help>
+    <help>Number of NS messages to send while performing DAD</help>
     <valueHelp>
       <format>u32:0</format>
       <description>Disable Duplicate Address Dectection (DAD)</description>
@@ -14,5 +14,6 @@
       <validator name="numeric" argument="--non-negative"/>
     </constraint>
   </properties>
+  <defaultValue>1</defaultValue>
 </leafNode>
 <!-- include end -->
diff --git a/interface-definitions/include/interface/vif-s.xml.i b/interface-definitions/include/interface/vif-s.xml.i
index 7a41bb242..89b5baf64 100644
--- a/interface-definitions/include/interface/vif-s.xml.i
+++ b/interface-definitions/include/interface/vif-s.xml.i
@@ -20,7 +20,7 @@
     #include <include/interface/disable.xml.i>
     <leafNode name="protocol">
       <properties>
-        <help>Protocol used for service VLAN (default: 802.1ad)</help>
+        <help>Protocol used for service VLAN</help>
         <completionHelp>
           <list>802.1ad 802.1q</list>
         </completionHelp>
diff --git a/interface-definitions/include/radius-server-port.xml.i b/interface-definitions/include/radius-server-port.xml.i
index 4e5d906bc..c6b691a0f 100644
--- a/interface-definitions/include/radius-server-port.xml.i
+++ b/interface-definitions/include/radius-server-port.xml.i
@@ -4,7 +4,7 @@
     <help>Authentication port</help>
     <valueHelp>
       <format>u32:1-65535</format>
-      <description>Numeric IP port (default: 1812)</description>
+      <description>Numeric IP port</description>
     </valueHelp>
     <constraint>
       <validator name="numeric" argument="--range 1-65535"/>