Helps if you add the new files

.changelog/4af5a11fb21842ffb627d5ee4d80fb14.md

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+---
+type: minor
+---
+Add new Templating proccors

octodns/processor/templating.py

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+#
+#
+#
+
+from octodns.processor.base import BaseProcessor
+
+
+class Templating(BaseProcessor):
+
+    def __init__(self, id, *args, **kwargs):
+        super().__init__(id, *args, **kwargs)
+
+    def process_source_zone(self, desired, sources):
+        sources = sources or []
+        zone_params = {
+            'zone_name': desired.decoded_name,
+            'zone_decoded_name': desired.decoded_name,
+            'zone_encoded_name': desired.name,
+            'zone_num_records': len(desired.records),
+            'zone_source_ids': ', '.join(s.id for s in sources),
+        }
+
+        def params(record):
+            return {
+                'record_name': record.decoded_name,
+                'record_decoded_name': record.decoded_name,
+                'record_encoded_name': record.name,
+                'record_fqdn': record.decoded_fqdn,
+                'record_decoded_fqdn': record.decoded_fqdn,
+                'record_encoded_fqdn': record.fqdn,
+                'record_type': record._type,
+                'record_ttl': record.ttl,
+                'record_source_id': record.source.id if record.source else None,
+                **zone_params,
+            }
+
+        for record in desired.records:
+            if hasattr(record, 'values'):
+                new_values = [v.template(params(record)) for v in record.values]
+                if record.values != new_values:
+                    new = record.copy()
+                    new.values = new_values
+                    desired.add_record(new, replace=True)
+            else:
+                new_value = record.value.template(params(record))
+                if record.value != new_value:
+                    new = record.copy()
+                    new.value = new_value
+                    desired.add_record(new, replace=True)
+
+        return desired

tests/test_octodns_processor_templating.py

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+#
+#
+#
+
+from unittest import TestCase
+from unittest.mock import call, patch
+
+from octodns.processor.templating import Templating
+from octodns.record import Record
+from octodns.zone import Zone
+
+
+def _find(zone, name):
+    return next(r for r in zone.records if r.name == name)
+
+
+class TemplatingTest(TestCase):
+    def test_cname(self):
+        templ = Templating('test')
+
+        zone = Zone('unit.tests.', [])
+        cname = Record.new(
+            zone,
+            'cname',
+            {
+                'type': 'CNAME',
+                'ttl': 42,
+                'value': '_cname.{zone_name}something.else.',
+            },
+            lenient=True,
+        )
+        zone.add_record(cname)
+        noop = Record.new(
+            zone,
+            'noop',
+            {
+                'type': 'CNAME',
+                'ttl': 42,
+                'value': '_noop.nothing_to_do.something.else.',
+            },
+            lenient=True,
+        )
+        zone.add_record(noop)
+
+        got = templ.process_source_zone(zone, None)
+        cname = _find(got, 'cname')
+        self.assertEqual('_cname.unit.tests.something.else.', cname.value)
+        noop = _find(got, 'noop')
+        self.assertEqual('_noop.nothing_to_do.something.else.', noop.value)
+
+    def test_txt(self):
+        templ = Templating('test')
+
+        zone = Zone('unit.tests.', [])
+        txt = Record.new(
+            zone,
+            'txt',
+            {
+                'type': 'TXT',
+                'ttl': 42,
+                'value': 'There are {zone_num_records} record(s) in {zone_name}',
+            },
+        )
+        zone.add_record(txt)
+        noop = Record.new(
+            zone,
+            'noop',
+            {'type': 'TXT', 'ttl': 43, 'value': 'Nothing to template here.'},
+        )
+        zone.add_record(noop)
+
+        got = templ.process_source_zone(zone, None)
+        txt = _find(got, 'txt')
+        self.assertEqual('There are 2 record(s) in unit.tests.', txt.values[0])
+        noop = _find(got, 'noop')
+        self.assertEqual('Nothing to template here.', noop.values[0])
+
+    @patch('octodns.record.TxtValue.template')
+    def test_params(self, mock_template):
+        templ = Templating('test')
+
+        class DummySource:
+
+            def __init__(self, id):
+                self.id = id
+
+        zone = Zone('unit.tests.', [])
+        record_source = DummySource('record')
+        txt = Record.new(
+            zone,
+            'txt',
+            {
+                'type': 'TXT',
+                'ttl': 42,
+                'value': 'There are {zone_num_records} record(s) in {zone_name}',
+            },
+            source=record_source,
+        )
+        zone.add_record(txt)
+
+        templ.process_source_zone(
+            zone, sources=[record_source, DummySource('other')]
+        )
+        mock_template.assert_called_once()
+        self.assertEqual(
+            call(
+                {
+                    'record_name': 'txt',
+                    'record_decoded_name': 'txt',
+                    'record_encoded_name': 'txt',
+                    'record_fqdn': 'txt.unit.tests.',
+                    'record_decoded_fqdn': 'txt.unit.tests.',
+                    'record_encoded_fqdn': 'txt.unit.tests.',
+                    'record_type': 'TXT',
+                    'record_ttl': 42,
+                    'record_source_id': 'record',
+                    'zone_name': 'unit.tests.',
+                    'zone_decoded_name': 'unit.tests.',
+                    'zone_encoded_name': 'unit.tests.',
+                    'zone_num_records': 1,
+                    'zone_source_ids': 'record, other',
+                }
+            ),
+            mock_template.call_args,
+        )