ddclient: T5574: Support per-service cache management for services

Add support for per-service cache management for ddclient providers
via `wait-time` and `expiry-time` options. This allows for finer-grained
control over how often a service is updated and how long the hostname
will be cached before being marked expired in ddclient's cache.

More specifically, `wait-time` controls how often ddclient will attempt
to check for a change in the hostname's IP address, and `expiry-time`
controls how often ddclient to a forced update of the hostname's IP
address.

These options intentionally don't have any default values because they
are provider-specific. They get treated similar to the other provider-
specific options in that they are only used if defined.

5 files changed, 49 insertions, 7 deletions

diff --git a/data/templates/dns-dynamic/ddclient.conf.j2 b/data/templates/dns-dynamic/ddclient.conf.j2
index 5905b19ea..6e77abdb5 100644
--- a/data/templates/dns-dynamic/ddclient.conf.j2
+++ b/data/templates/dns-dynamic/ddclient.conf.j2
@@ -14,10 +14,8 @@ if{{ ipv }}={{ address }}, \
 {%     endif %}
 {% endfor %}
 {# Other service options #}
-{% for k,v in kwargs.items() %}
-{%     if v is vyos_defined %}
-{{ k }}={{ v }}{{ ',' if not loop.last }} \
-{%     endif %}
+{% for k,v in kwargs.items() if v is vyos_defined %}
+{{ k | replace('_', '-') }}={{ v }}{{ ',' if not loop.last }} \
 {% endfor %}
 {# Actual hostname for the service #}
 {{ host }}
@@ -49,7 +47,6 @@ use=no
 {{ render_config(host, address, service_cfg.web_options,
                  protocol='nsupdate', server=config.server, zone=config.zone,
                  password=config.key, ttl=config.ttl) }}
-
 {%                 endfor %}
 {%             endfor %}
 {%         endif %}
@@ -66,8 +63,8 @@ use=no
 # Web service dynamic DNS configuration for {{ name }}: [{{ config.protocol }}, {{ host }}]
 {{ render_config(host, address, service_cfg.web_options, ip_suffixes,
                  protocol=config.protocol, server=config.server, zone=config.zone,
-                 login=config.username, password=config.password, ttl=config.ttl) }}
-
+                 login=config.username, password=config.password, ttl=config.ttl,
+                 min_interval=config.wait_time, max_interval=config.expiry_time) }}
 {%                 endfor %}
 {%             endfor %}
 {%         endif %}
diff --git a/interface-definitions/dns-dynamic.xml.in b/interface-definitions/dns-dynamic.xml.in
index ba7f426c1..723223f1c 100644
--- a/interface-definitions/dns-dynamic.xml.in
+++ b/interface-definitions/dns-dynamic.xml.in
@@ -61,6 +61,7 @@
                     <children>
                       #include <include/generic-description.xml.i>
                       #include <include/dns/dynamic-service-host-name-server.xml.i>
+                      #include <include/dns/dynamic-service-wait-expiry-time.xml.i>
                       <leafNode name="key">
                         <properties>
                           <help>File containing the TSIG secret key shared with remote DNS server</help>
@@ -88,6 +89,7 @@
                     <children>
                       #include <include/generic-description.xml.i>
                       #include <include/dns/dynamic-service-host-name-server.xml.i>
+                      #include <include/dns/dynamic-service-wait-expiry-time.xml.i>
                       #include <include/generic-username.xml.i>
                       #include <include/generic-password.xml.i>
                       #include <include/dns/time-to-live.xml.i>
diff --git a/interface-definitions/include/dns/dynamic-service-wait-expiry-time.xml.i b/interface-definitions/include/dns/dynamic-service-wait-expiry-time.xml.i
new file mode 100644
index 000000000..866690cbe
--- /dev/null
+++ b/interface-definitions/include/dns/dynamic-service-wait-expiry-time.xml.i
@@ -0,0 +1,28 @@
+<!-- include start from dns/dynamic-service-wait-expiry-time.xml.i -->
+<leafNode name="wait-time">
+  <properties>
+    <help>Time in seconds to wait between update attempts</help>
+    <valueHelp>
+      <format>u32:60-86400</format>
+      <description>Time in seconds</description>
+    </valueHelp>
+    <constraint>
+      <validator name="numeric" argument="--range 60-86400"/>
+    </constraint>
+    <constraintErrorMessage>Wait time must be between 60 and 86400 seconds</constraintErrorMessage>
+  </properties>
+</leafNode>
+<leafNode name="expiry-time">
+  <properties>
+    <help>Time in seconds for the hostname to be marked expired in cache</help>
+    <valueHelp>
+      <format>u32:300-2160000</format>
+      <description>Time in seconds</description>
+    </valueHelp>
+    <constraint>
+      <validator name="numeric" argument="--range 300-2160000"/>
+    </constraint>
+    <constraintErrorMessage>Expiry time must be between 300 and 2160000 seconds</constraintErrorMessage>
+  </properties>
+</leafNode>
+<!-- include end -->
diff --git a/smoketest/scripts/cli/test_service_dns_dynamic.py b/smoketest/scripts/cli/test_service_dns_dynamic.py
index 66dcde434..acabc0070 100755
--- a/smoketest/scripts/cli/test_service_dns_dynamic.py
+++ b/smoketest/scripts/cli/test_service_dns_dynamic.py
@@ -116,6 +116,9 @@ class TestServiceDDNS(VyOSUnitTestSHIM.TestCase):
         svc_path = ['address', interface, 'service', 'dynv6']
         proto = 'dyndns2'
         ip_version = 'ipv6'
+        wait_time = '600'
+        expiry_time_good = '3600'
+        expiry_time_bad = '360'
 
         self.cli_set(base_path + ['timeout', timeout])
         self.cli_set(base_path + svc_path + ['ip-version', ip_version])
@@ -124,6 +127,13 @@ class TestServiceDDNS(VyOSUnitTestSHIM.TestCase):
         self.cli_set(base_path + svc_path + ['username', username])
         self.cli_set(base_path + svc_path + ['password', password])
         self.cli_set(base_path + svc_path + ['host-name', hostname])
+        self.cli_set(base_path + svc_path + ['wait-time', wait_time])
+
+        # expiry-time must be greater than wait-time, exception is raised otherwise
+        self.cli_set(base_path + svc_path + ['expiry-time', expiry_time_bad])
+        with self.assertRaises(ConfigSessionError):
+            self.cli_commit()
+        self.cli_set(base_path + svc_path + ['expiry-time', expiry_time_good])
 
         # commit changes
         self.cli_commit()
@@ -137,6 +147,8 @@ class TestServiceDDNS(VyOSUnitTestSHIM.TestCase):
         self.assertIn(f'server={server}', ddclient_conf)
         self.assertIn(f'login={username}', ddclient_conf)
         self.assertIn(f'password={password}', ddclient_conf)
+        self.assertIn(f'min-interval={wait_time}', ddclient_conf)
+        self.assertIn(f'max-interval={expiry_time_good}', ddclient_conf)
 
     # IPv4+IPv6 dual DDNS service configuration
     def test_03_dyndns_service_dual_stack(self):
diff --git a/src/conf_mode/dns_dynamic.py b/src/conf_mode/dns_dynamic.py
index 8a438cf6f..874c4b689 100755
--- a/src/conf_mode/dns_dynamic.py
+++ b/src/conf_mode/dns_dynamic.py
@@ -111,6 +111,9 @@ def verify(dyndns):
                         raise ConfigError(f'"{config["protocol"]}" does not support '
                                           f'both IPv4 and IPv6 at the same time for "{config["server"]}"')
 
+                if {'wait_time', 'expiry_time'} <= config.keys() and int(config['expiry_time']) < int(config['wait_time']):
+                        raise ConfigError(f'"expiry-time" must be greater than "wait-time"')
+
     return None
 
 def generate(dyndns):