Add Processor.process_source_and_target_zones

CHANGELOG.md

@@ -1,6 +1,8 @@
 ## v1.?.0 - 2023-??-?? -
 
 * Record.lenient property added similar to other common/standard _octodns data
+* Processor.process_source_and_target_zones added to support modifying both the
+  desired and/or existing zones just prior to computing changes.
 
 ## v1.3.0 - 2023-11-14 - New and improved processors
 

octodns/processor/base.py

@@ -37,7 +37,7 @@ class BaseProcessor(object):
         computed between `existing` and `desired`. This provides an opportunity
         to modify the `existing` `Zone`.
 
-        - Will see `existing` after any modifrications done by processors
+        - Will see `existing` after any modifications done by processors
           configured to run before this one.
         - May modify `existing` directly.
         - Must return `existing` which will normally be the `existing` param.
@@ -48,6 +48,33 @@ class BaseProcessor(object):
         '''
         return existing
 
+    def process_source_and_target_zones(self, desired, existing, target):
+        '''
+        Called just prior to computing changes for `target` between `desired`
+        and `existing`. Provides an opportunity for the processor to modify
+        either the desired or existing `Zone`s that will be used to compute the
+        changes and create the initial plan.
+
+        - Will see `desired` after any modifications done by
+          `Provider._process_desired_zone` and all processors via
+          `Processor.process_source_zone`
+        - Will see `existing` after any modifications done by all processors
+          via `Processor.process_target_zone`
+        - Will see both `desired` and `existing` after any modifications done by
+          any processors configured to run before this one via
+          `Processor.process_source_and_target_zones`.
+        - May modify `desired` directly.
+        - Must return `desired` which will normally be the `desired` param.
+        - May modify `existing` directly.
+        - Must return `existing` which will normally be the `existing` param.
+        - Must not modify records directly, `record.copy` should be called,
+          the results of which can be modified, and then `Zone.add_record` may
+          be used with `replace=True`.
+        - May call `Zone.remove_record` to remove records from `desired`.
+        - May call `Zone.remove_record` to remove records from `existing`.
+        '''
+        return desired, existing
+
     def process_plan(self, plan, sources, target):
         '''
         Called after the planning phase has completed. Provides an opportunity

octodns/provider/base.py

@@ -243,6 +243,11 @@ class BaseProvider(BaseSource):
         for processor in processors:
             existing = processor.process_target_zone(existing, target=self)
 
+        for processor in processors:
+            desired, existing = processor.process_source_and_target_zones(
+                desired, existing, self
+            )
+
         # compute the changes at the zone/record level
         changes = existing.changes(desired, self)
 

tests/test_octodns_manager.py

@@ -25,7 +25,7 @@ from octodns.manager import (
     _AggregateTarget,
 )
 from octodns.processor.base import BaseProcessor
-from octodns.record import Create, Delete, Record
+from octodns.record import Create, Delete, Record, Update
 from octodns.yaml import safe_load
 from octodns.zone import Zone
 
@@ -723,6 +723,50 @@ class TestManager(TestCase):
         # We got a delete for the thing added to the existing state (target)
         self.assertIsInstance(plans[0][1].changes[0], Delete)
 
+        # source & target
+        record2 = Record.new(
+            zone, 'a2', {'ttl': 31, 'type': 'A', 'value': '1.2.3.4'}
+        )
+        record3 = Record.new(
+            zone, 'a3', {'ttl': 32, 'type': 'A', 'value': '1.2.3.4'}
+        )
+
+        class MockProcessor(BaseProcessor):
+            def process_source_and_target_zones(
+                self, desired, existing, target
+            ):
+                # add something to desired
+                desired.add_record(record2)
+                # add something to existing
+                existing.add_record(record3)
+                # add something to both, but with a modification
+                desired.add_record(record)
+                mod = record.copy()
+                mod.ttl += 1
+                existing.add_record(mod)
+                return desired, existing
+
+        mock = MockProcessor('mock')
+        plans, zone = manager._populate_and_plan(
+            'unit.tests.', [mock], [], targets
+        )
+        # we should see a plan
+        self.assertTrue(plans)
+        plan = plans[0][1]
+        # it shoudl have a create, an update, and a delete
+        self.assertEqual(
+            'a',
+            next(c.record.name for c in plan.changes if isinstance(c, Update)),
+        )
+        self.assertEqual(
+            'a2',
+            next(c.record.name for c in plan.changes if isinstance(c, Create)),
+        )
+        self.assertEqual(
+            'a3',
+            next(c.record.name for c in plan.changes if isinstance(c, Delete)),
+        )
+
         # muck with plans
         class MockProcessor(BaseProcessor):
             def process_target_zone(self, zone, target):