Add list_zones to AutoArpa

- This makes it possible to use dynamic zone config with AutoArpa
- Document what gotchas that entails
- Add tests both with another source (for generating zones to populate) and without (no zones to populate)

tests/config/dynamic-arpa-no-normal-source.yaml

@@ -0,0 +1,29 @@
+manager:
+  max_workers: 2
+  auto_arpa:
+    populate_should_replace: True
+    ttl: 1800
+
+providers:
+  in:
+    class: octodns.provider.yaml.YamlProvider
+    directory: tests/config/dynamic-arpa
+    supports_root_ns: False
+    strict_supports: False
+  dump:
+    class: octodns.provider.yaml.YamlProvider
+    directory: env/YAML_TMP_DIR
+    default_ttl: 999
+    supports_root_ns: False
+    strict_supports: False
+zones:
+  unit.tests.:
+    sources:
+    - in
+    targets:
+    - dump
+  "*.arpa.":
+    sources:
+    - auto-arpa
+    targets:
+    - dump

tests/config/dynamic-arpa.yaml

@@ -0,0 +1,30 @@
+manager:
+  max_workers: 2
+  auto_arpa:
+    populate_should_replace: True
+    ttl: 1800
+
+providers:
+  in:
+    class: octodns.provider.yaml.YamlProvider
+    directory: tests/config/dynamic-arpa
+    supports_root_ns: False
+    strict_supports: False
+  dump:
+    class: octodns.provider.yaml.YamlProvider
+    directory: env/YAML_TMP_DIR
+    default_ttl: 999
+    supports_root_ns: False
+    strict_supports: False
+zones:
+  unit.tests.:
+    sources:
+    - in
+    targets:
+    - dump
+  "*.arpa.":
+    sources:
+    - in
+    - auto-arpa
+    targets:
+    - dump

tests/config/dynamic-arpa/unit.tests.yaml

@@ -0,0 +1,17 @@
+---
+aaaa:
+  ttl: 600
+  type: AAAA
+  value: 2601:644:500:e210:62f8:1dff:feb8:947a
+not-a-zone-file:
+  ttl: 300
+  type: A
+  value: 3.3.3.6
+www:
+  ttl: 300
+  type: A
+  value: 2.2.3.6
+www.sub:
+  ttl: 300
+  type: A
+  value: 2.2.3.7

tests/test_octodns_manager.py

@@ -1099,6 +1099,26 @@ class TestManager(TestCase):
             # should sync everything across all zones, total of 32 records
             self.assertEqual(32, manager.sync(dry_run=False))
 
+    def test_dynamic_config_with_arpa(self):
+        with TemporaryDirectory() as tmpdir:
+            environ['YAML_TMP_DIR'] = tmpdir.dirname
+            manager = Manager(get_config_filename('dynamic-arpa.yaml'))
+
+            # should sync everything across all zones, total of 7 records
+            # 4 normal records and 3 arpa records generated
+            self.assertEqual(4 + 3, manager.sync(dry_run=False))
+
+    def test_dynamic_config_with_arpa_no_normal_source(self):
+        with TemporaryDirectory() as tmpdir:
+            environ['YAML_TMP_DIR'] = tmpdir.dirname
+            manager = Manager(
+                get_config_filename('dynamic-arpa-no-normal-source.yaml')
+            )
+
+            # should sync everything across all zones, total of 4 records
+            # 4 normal records and 0 arpa records generated since no zones to populate was found
+            self.assertEqual(4, manager.sync(dry_run=False))
+
     def test_dynamic_config_unsupported_zone(self):
         manager = Manager(
             get_config_filename('dynamic-config-no-list-zones.yaml')