20260907 - Default the Doppler span to +/-300 Hz and let it reach deployed nodes

config-merger/script/merge_config.py

@@ -32,6 +32,12 @@
 import yaml
 from mergedeep import merge
 
+# The Doppler span default.yml shipped up to and including v0.4.5.0. A user.yml
+# holding exactly this pair is assumed to be the merger's own first-boot copy
+# rather than anyone's choice. See migrate_doppler_span().
+LEGACY_DOPPLER_MIN = -200
+LEGACY_DOPPLER_MAX = 200
+
 
 def get_node_id_from_mender():
     """Read node_id from Mender device identity file (generated by mender-device-identity)"""
@@ -157,6 +163,41 @@ def migrate_gain_reduction(config):
         config['capture']['device']['gainReduction'] = [gain, gain]
 
 
+def migrate_doppler_span(user):
+    """Drop a Doppler span the user never chose, so default.yml can change it.
+
+    On first boot the merger seeds user.yml with a whole copy of default.yml, so
+    every deployed node persists the shipped Doppler span whether or not anyone
+    selected it. Without this, a change to default.yml could never reach a node
+    that has already booted once.
+
+    Only the exact legacy pair is dropped, and only when both bounds match: any
+    other value is a deliberate setting and is left alone. owl runs +/-1000 Hz,
+    which must survive. A node that genuinely wants +/-200 Hz is indistinguishable
+    from a first-boot copy, so it moves to the new default and has to be set
+    again if that is not wanted.
+
+    Dropping the keys rather than rewriting them means whatever default.yml ships
+    takes effect, including a later change to some other value. user.yml on disk
+    is untouched, so this stays load-bearing: remove it and nodes fall back to
+    the +/-200 Hz their overlay still holds.
+    """
+    try:
+        ambiguity = user['process']['ambiguity']
+    except (KeyError, TypeError):
+        return
+
+    if not isinstance(ambiguity, dict):
+        return
+
+    if (ambiguity.get('dopplerMin') == LEGACY_DOPPLER_MIN
+            and ambiguity.get('dopplerMax') == LEGACY_DOPPLER_MAX):
+        print(f"Dropping first-boot Doppler span ({LEGACY_DOPPLER_MIN}/{LEGACY_DOPPLER_MAX} Hz) "
+              "from user config so the shipped default applies")
+        del ambiguity['dopplerMin']
+        del ambiguity['dopplerMax']
+
+
 def ensure_node_id(user_config_path):
     """Add/update node_id in user config from Mender device identity"""
     try:
@@ -253,6 +294,7 @@ def main():
 
             if user:  # Only merge if user.yml has actual content
                 print("Applying user overrides...")
+                migrate_doppler_span(user)
                 merge(config, user)
             else:
                 print("User config is empty, using defaults")

config-merger/test/test_merge_config.py

@@ -617,5 +617,106 @@ def test_retina_tracker_yaml_user_override(self):
         self.assertEqual(output['tracker']['min_snr'], 4.5)
 
 
+    # --- Doppler span migration -------------------------------------------
+    # The merger seeds user.yml from default.yml on first boot, so every node
+    # persists the shipped span. These cover which of those persisted values
+    # the merger is allowed to move.
+
+    def default_with_span(self, doppler_min=-300, doppler_max=300):
+        """A default.yml carrying the shipped ambiguity block."""
+        return {
+            'process': {
+                'ambiguity': {
+                    'delayMin': -10,
+                    'delayMax': 400,
+                    'dopplerMin': doppler_min,
+                    'dopplerMax': doppler_max,
+                }
+            }
+        }
+
+    def write_span_configs(self, user_ambiguity, forced_config=None):
+        """Write a default/user/forced set differing only in the ambiguity block."""
+        self.write_yaml(os.path.join(self.defaults_dir, 'default.yml'), self.default_with_span())
+        self.write_yaml(os.path.join(self.defaults_dir, 'forced.yml'), forced_config or {})
+        self.write_yaml(os.path.join(self.config_dir, 'user.yml'),
+                        {'process': {'ambiguity': user_ambiguity}})
+
+    def test_doppler_span_first_boot_copy_migrated(self):
+        """A user.yml holding the old shipped span gives way to the new default"""
+        self.write_span_configs({'delayMin': -10, 'delayMax': 400,
+                                 'dopplerMin': -200, 'dopplerMax': 200})
+
+        output = self.read_yaml(self.run_merge())
+        ambiguity = output['process']['ambiguity']
+
+        self.assertEqual(ambiguity['dopplerMin'], -300)
+        self.assertEqual(ambiguity['dopplerMax'], 300)
+        # Only the Doppler bounds move; the rest of the block is the user's.
+        self.assertEqual(ambiguity['delayMin'], -10)
+        self.assertEqual(ambiguity['delayMax'], 400)
+
+    def test_doppler_span_deliberate_override_kept(self):
+        """A span nobody could have got from a first-boot copy survives"""
+        self.write_span_configs({'dopplerMin': -1000, 'dopplerMax': 1000})
+
+        output = self.read_yaml(self.run_merge())
+
+        self.assertEqual(output['process']['ambiguity']['dopplerMin'], -1000)
+        self.assertEqual(output['process']['ambiguity']['dopplerMax'], 1000)
+
+    def test_doppler_span_partial_legacy_match_kept(self):
+        """One legacy bound is not the legacy pair, so neither bound moves"""
+        self.write_span_configs({'dopplerMin': -200, 'dopplerMax': 1000})
+
+        output = self.read_yaml(self.run_merge())
+
+        self.assertEqual(output['process']['ambiguity']['dopplerMin'], -200)
+        self.assertEqual(output['process']['ambiguity']['dopplerMax'], 1000)
+
+    def test_doppler_span_asymmetric_legacy_value_kept(self):
+        """An asymmetric span that happens to touch 200 is still deliberate"""
+        self.write_span_configs({'dopplerMin': -200, 'dopplerMax': 400})
+
+        output = self.read_yaml(self.run_merge())
+
+        self.assertEqual(output['process']['ambiguity']['dopplerMin'], -200)
+        self.assertEqual(output['process']['ambiguity']['dopplerMax'], 400)
+
+    def test_doppler_span_forced_still_wins(self):
+        """forced.yml keeps the last word over a migrated span"""
+        self.write_span_configs(
+            {'dopplerMin': -200, 'dopplerMax': 200},
+            forced_config={'process': {'ambiguity': {'dopplerMin': -250, 'dopplerMax': 250}}},
+        )
+
+        output = self.read_yaml(self.run_merge())
+
+        self.assertEqual(output['process']['ambiguity']['dopplerMin'], -250)
+        self.assertEqual(output['process']['ambiguity']['dopplerMax'], 250)
+
+    def test_doppler_span_migration_does_not_rewrite_user_yml(self):
+        """The overlay on disk is untouched, so the migration has to stay in place"""
+        self.write_span_configs({'dopplerMin': -200, 'dopplerMax': 200})
+
+        self.run_merge()
+
+        user = self.read_yaml(os.path.join(self.config_dir, 'user.yml'))
+        self.assertEqual(user['process']['ambiguity']['dopplerMin'], -200)
+        self.assertEqual(user['process']['ambiguity']['dopplerMax'], 200)
+
+    def test_doppler_span_absent_from_user_config(self):
+        """A user.yml with no ambiguity block just takes the default"""
+        self.write_yaml(os.path.join(self.defaults_dir, 'default.yml'), self.default_with_span())
+        self.write_yaml(os.path.join(self.defaults_dir, 'forced.yml'), {})
+        self.write_yaml(os.path.join(self.config_dir, 'user.yml'),
+                        {'network': {'node_id': 'test-node'}})
+
+        output = self.read_yaml(self.run_merge())
+
+        self.assertEqual(output['process']['ambiguity']['dopplerMin'], -300)
+        self.assertEqual(output['process']['ambiguity']['dopplerMax'], 300)
+
+
 if __name__ == '__main__':
     unittest.main()

config/default.yml

@@ -22,8 +22,8 @@ process:
   ambiguity:
     delayMin: -10
     delayMax: 400
-    dopplerMin: -200
-    dopplerMax: 200
+    dopplerMin: -300
+    dopplerMax: 300
   clutter:
     enable: true
     delayMin: -10