refactor(transport): derive active transports from config, drop transport setting (#13)

* refactor(transport): derive active transports from config, drop transport setting

A mesh is active when its connection is configured: Meshtastic is the
always-on base; MeshCore runs whenever meshcore_host is set (blank = off);
both configured = both. Removes the transport mode field/toggle entirely
so there's no separate flag to miss.

* docs: fix stale transport comment after field removal

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

---------

Co-authored-by: Matt Johnson <mj@k7zvx.com>
Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>

work/dashboard-frontend/src/pages/Config.tsx

@@ -25,7 +25,6 @@ export interface ConnectionConfig {
   serial_port: string
   tcp_host: string
   tcp_port: number
-  transport?: string
   meshcore_host?: string
   meshcore_port?: number
 }
@@ -751,14 +750,14 @@ export function ConnectionSection({ data, onChange }: { data: ConnectionConfig;
           />
         </div>
       )}
-      {/* MeshCore transport + host/port live on their own first-class page
+      {/* MeshCore host/port live on their own first-class page
           (/meshcore/connection). Subtle cross-link only — no editable fields here. */}
       <div className="pt-2">
         <Link
           to="/meshcore/connection"
           className="inline-flex items-center gap-1 text-xs text-slate-500 hover:text-accent transition-colors"
         >
-          &rarr; MeshCore transport &amp; connection
+          &rarr; MeshCore connection
         </Link>
       </div>
     </div>

work/dashboard-frontend/src/pages/MeshCoreConnection.tsx

@@ -14,7 +14,6 @@ interface ConnectionConfig {
   serial_port?: string
   tcp_host?: string
   tcp_port?: number
-  transport?: string
   meshcore_host?: string
   meshcore_port?: number
   [key: string]: unknown
@@ -159,54 +158,28 @@ export default function MeshCoreConnection() {
 
       {/* Form */}
       <div className="bg-bg-card border border-border p-6 space-y-4">
-        <div className="flex items-center justify-between py-2">
-          <div>
-            <span className="text-sm text-slate-300">Enable MeshCore</span>
-            <p className="text-xs text-slate-600">
-              Meshtastic is always on; enabling adds MeshCore (Both).
-            </p>
-          </div>
-          <button
-            type="button"
-            onClick={() => {
-              const checked = !(config.transport === 'both' || config.transport === 'meshcore')
-              upd({ transport: checked ? 'both' : 'meshtastic' })
-            }}
-            className={`relative w-11 h-6 rounded-full transition-colors ${
-              config.transport === 'both' || config.transport === 'meshcore'
-                ? 'bg-accent'
-                : 'bg-[#1e2a3a]'
-            }`}
-          >
-            <span
-              className={`absolute top-1 left-1 w-4 h-4 rounded-full bg-white transition-transform ${
-                config.transport === 'both' || config.transport === 'meshcore'
-                  ? 'translate-x-5'
-                  : ''
-              }`}
-            />
-          </button>
-        </div>
-        <div className="pt-2 border-t border-[#1e2a3a] space-y-4">
-          <div className="text-xs text-slate-500 uppercase tracking-wide">MeshCore Connection</div>
-          <div className="grid grid-cols-2 gap-4">
-            <TextInput
-              label="MeshCore Host"
-              value={config.meshcore_host ?? ''}
-              onChange={(v) => upd({ meshcore_host: v })}
-              placeholder="192.168.1.100"
-              helper="IP or hostname of the MeshCore node"
-              info="Address of the MeshCore node to connect to."
-            />
-            <NumberInput
-              label="MeshCore Port"
-              value={config.meshcore_port ?? 5525}
-              onChange={(v) => upd({ meshcore_port: v })}
-              min={1}
-              max={65535}
-              helper="MeshCore TCP port (default 5525)"
-            />
-          </div>
+        <div className="text-xs text-slate-500 uppercase tracking-wide">MeshCore Connection</div>
+        <p className="text-xs text-slate-500">
+          Set the host and port to enable MeshCore; leave host blank to disable.
+          Meshtastic is always active.
+        </p>
+        <div className="grid grid-cols-2 gap-4">
+          <TextInput
+            label="MeshCore Host"
+            value={config.meshcore_host ?? ''}
+            onChange={(v) => upd({ meshcore_host: v })}
+            placeholder="192.168.1.100"
+            helper="IP or hostname — leave blank to disable MeshCore"
+            info="MeshCore is active when this field is non-empty."
+          />
+          <NumberInput
+            label="MeshCore Port"
+            value={config.meshcore_port ?? 5525}
+            onChange={(v) => upd({ meshcore_port: v })}
+            min={1}
+            max={65535}
+            helper="MeshCore TCP port (default 5525)"
+          />
         </div>
         <div className="pt-2">
           <Link

work/meshai/config.py

@@ -34,12 +34,11 @@ class ConnectionConfig:
     reconnect_initial_delay: float = 2.0
     reconnect_max_delay: float = 60.0
     reconnect_health_interval: float = 30.0
-    # --- transport selection (Phase 1 seam; MeshCore support is Phase 2) ---
-    transport: str = "meshtastic"  # "meshtastic" | "meshcore" | "both"
     # Universal mesh message budget (MeshCore LCD → 140 for all transports).
     mesh_max_chars: int = 140
-    # --- MeshCore transport settings (used when transport="meshcore") ---
-    meshcore_host: str = "100.64.0.9"          # pyMC companion frame server host
+    # --- MeshCore transport settings ---
+    # MeshCore is active when meshcore_host is a non-empty string; blank = off.
+    meshcore_host: str = ""                     # pyMC companion frame server host
     meshcore_port: int = 5050                   # pyMC companion frame server port
     meshcore_auto_reconnect: bool = True        # enable meshcore lib auto-reconnect
     meshcore_max_reconnect_attempts: int = 5    # max reconnect attempts (0 = unlimited)

work/meshai/main.py

@@ -394,7 +394,7 @@ class MeshAI:
         # Load persisted summaries into memory cache
         await self._load_summaries()
 
-        # Transport connector (factory selects backend from config.connection.transport)
+        # Transport connector (factory derives backend from config.connection.meshcore_host)
         self.connector = build_transport(self.config.connection)
 
         # Fit every broadcast handler's one-packet formatter to the active mesh

work/meshai/notifications/channels.py

@@ -250,7 +250,7 @@ class MeshCoreBroadcastChannel(NotificationChannel):
             return {
                 "success": False,
                 "message": "No MeshCore transport available",
-                "error": "Set connection.transport to 'meshcore' or 'both'",
+                "error": "Set connection.meshcore_host to enable MeshCore",
                 "details": {"meshcore_channel": self._meshcore_channel},
             }
         return {
@@ -469,7 +469,7 @@ class MeshCoreDMChannel(NotificationChannel):
             return {
                 "success": False,
                 "message": "No MeshCore transport available",
-                "error": "Set connection.transport to 'meshcore' or 'both'",
+                "error": "Set connection.meshcore_host to enable MeshCore",
                 "details": {"contacts": self._contacts},
             }
         if not self._contacts:

work/meshai/transport/composite_transport.py

@@ -7,10 +7,9 @@ Holds an ordered list of child transports and:
   - self-filters inbound messages per child (drops own echoes);
   - exposes ``meshtastic_child()`` for the supervisor watchdog.
 
-This transport is DORMANT unless ``transport: both`` in config.  Single-
-transport paths (``transport: meshtastic`` / ``transport: meshcore``) are
-byte-identical to Phase 3 behaviour because the factory never instantiates
-this class for them.
+This transport is active when ``meshcore_host`` is configured (non-empty).
+The factory instantiates it only when MeshCore is configured; Meshtastic-only
+configs receive a bare MeshtasticTransport instead.
 """
 
 import asyncio

work/meshai/transport/factory.py

@@ -4,44 +4,29 @@ from .base import MeshTransport
 
 
 def build_transport(config) -> MeshTransport:
-    """Instantiate and return the configured MeshTransport.
+    """Instantiate and return the active MeshTransport derived from config.
+
+    The active transports are derived from the connection config, not a
+    separate mode flag:
+
+    - Meshtastic is always the base transport.
+    - MeshCore is active when ``config.meshcore_host`` is a non-empty string.
+    - Both configured → CompositeTransport wrapping both.
+    - MeshCore host blank (default) → Meshtastic only.
 
     Args:
-        config: A ConnectionConfig (or duck-compatible object).  The
-                ``transport`` field selects the backend; it defaults to
-                ``"meshtastic"`` so existing configs require no changes.
+        config: A ConnectionConfig (or duck-compatible object).
 
     Returns:
         A concrete MeshTransport instance ready to be connected.
-
-    Raises:
-        ValueError: When the transport name is unrecognised.
     """
-    transport_name = getattr(config, "transport", "meshtastic")
+    from meshai.connector import MeshtasticTransport
+    meshtastic = MeshtasticTransport(config)
 
-    if transport_name == "meshtastic":
-        # Import here to avoid a circular import at module load time.
-        from meshai.connector import MeshtasticTransport
-        return MeshtasticTransport(config)
-
-    if transport_name == "meshcore":
-        # Function-local import keeps the module importable without the meshcore
-        # lib installed (lazy import pattern mirrors the meshtastic case).
-        from meshai.transport.meshcore_transport import MeshCoreTransport
-        return MeshCoreTransport(config)
-
-    if transport_name == "both":
-        # Phase 4: composite transport — drives Meshtastic and MeshCore
-        # simultaneously with correct reply routing.
-        from meshai.connector import MeshtasticTransport
+    meshcore_host = getattr(config, "meshcore_host", "") or ""
+    if meshcore_host.strip():
         from meshai.transport.meshcore_transport import MeshCoreTransport
         from meshai.transport.composite_transport import CompositeTransport
-        return CompositeTransport([
-            MeshtasticTransport(config),
-            MeshCoreTransport(config),
-        ], config=config)
+        return CompositeTransport([meshtastic, MeshCoreTransport(config)], config=config)
 
-    raise ValueError(
-        f"Unknown transport {transport_name!r}. "
-        "Expected one of: 'meshtastic', 'meshcore', 'both'."
-    )
+    return meshtastic

work/meshai/transport/meshcore_transport.py

@@ -33,9 +33,9 @@ class MeshCoreTransport(MeshTransport):
     The meshcore client (``self._mc``) is created and used exclusively on that
     loop.
 
-    The transport is dormant until ``connect()`` is called.  When
-    ``transport != "meshcore"`` in config the factory never instantiates this
-    class, so there is zero cost to existing meshtastic deployments.
+    The transport is dormant until ``connect()`` is called.  The factory
+    only instantiates this class when ``meshcore_host`` is non-empty, so
+    there is zero cost to Meshtastic-only deployments.
     """
 
     # Name tag used by CompositeTransport for routing hints.

work/tests/test_composite_transport.py

@@ -142,7 +142,7 @@ class TestMaxChars:
     def test_fixed_universal_budget_from_config(self) -> None:
         """With a config, CompositeTransport reads mesh_max_chars directly."""
         from meshai.config import ConnectionConfig
-        cfg = ConnectionConfig(transport="both", mesh_max_chars=140)
+        cfg = ConnectionConfig(mesh_max_chars=140)
         mt = FakeChild("meshtastic", max_chars_val=200)
         mc = FakeChild("meshcore", max_chars_val=140)
         comp = CompositeTransport([mt, mc], config=cfg)
@@ -151,7 +151,7 @@ class TestMaxChars:
     def test_fixed_universal_budget_ignores_child_values(self) -> None:
         """CompositeTransport must NOT take min(children); it sources config."""
         from meshai.config import ConnectionConfig
-        cfg = ConnectionConfig(transport="both", mesh_max_chars=140)
+        cfg = ConnectionConfig(mesh_max_chars=140)
         # Even if a child would report 230, the composite must return 140.
         child = FakeChild("meshtastic", max_chars_val=230)
         comp = CompositeTransport([child], config=cfg)

work/tests/test_meshcore_transport.py

@@ -94,9 +94,8 @@ from meshai.transport.meshcore_transport import MeshCoreTransport  # noqa: E402
 # ---------------------------------------------------------------------------
 
 def _mc_config(**overrides):
-    """Return a ConnectionConfig wired for meshcore."""
+    """Return a ConnectionConfig with meshcore_host set (activates MeshCore)."""
     cfg = ConnectionConfig(
-        transport="meshcore",
         meshcore_host="127.0.0.1",
         meshcore_port=5050,
     )
@@ -186,11 +185,16 @@ def _install_channel_table(mc, table=None):
 # ---------------------------------------------------------------------------
 
 class TestBuildTransport:
-    def test_returns_meshcore_transport(self):
+    def test_returns_composite_when_meshcore_host_set(self):
+        """meshcore_host set → build_transport returns CompositeTransport."""
+        from meshai.transport.composite_transport import CompositeTransport
         t = build_transport(_mc_config())
-        assert isinstance(t, MeshCoreTransport)
+        assert isinstance(t, CompositeTransport)
+        # MeshCoreTransport must be the second child.
+        assert isinstance(t.children[1], MeshCoreTransport)
 
     def test_is_mesh_transport_subclass(self):
+        """CompositeTransport (returned when meshcore_host is set) is a MeshTransport."""
         t = build_transport(_mc_config())
         assert isinstance(t, MeshTransport)
 

work/tests/test_transport_abstraction.py

@@ -1,10 +1,9 @@
-"""Lightweight tests for the Phase-1 MeshTransport abstraction.
+"""Tests for the MeshTransport abstraction and derive-from-config factory.
 
-These tests exercise the structural contracts introduced by the refactor:
+These tests exercise:
   - MeshtasticTransport is a concrete subclass of MeshTransport
-  - build_transport returns the right type for the default config
-  - build_transport raises appropriately for unimplemented / unknown transports
-  - MeshMessage has the new additive fields with the expected defaults
+  - build_transport derives active transports from meshcore_host, not a flag
+  - MeshMessage has the expected transport-routing fields with correct defaults
 
 No real radio, socket, or asyncio loop is required.
 """
@@ -47,50 +46,78 @@ class TestMeshtasticTransportABC:
 
 
 # ---------------------------------------------------------------------------
-# Factory
+# Factory — transports derived from meshcore_host, not a transport flag
 # ---------------------------------------------------------------------------
 
 
 class TestBuildTransport:
-    def _default_config(self):
-        return ConnectionConfig()  # transport defaults to "meshtastic"
+    def _config_no_meshcore(self):
+        """Default config: meshcore_host is blank → Meshtastic only."""
+        return ConnectionConfig()
 
-    def _config_with(self, transport_name):
+    def _config_with_meshcore(self, host="1.2.3.4"):
+        """Config with a non-empty meshcore_host → composite."""
         cfg = ConnectionConfig()
-        cfg.transport = transport_name
+        cfg.meshcore_host = host
         return cfg
 
-    def test_default_config_returns_meshtastic_transport(self):
-        cfg = self._default_config()
+    def test_blank_host_returns_meshtastic_only(self):
+        """Empty meshcore_host → MeshtasticTransport, no composite."""
+        cfg = self._config_no_meshcore()
+        assert cfg.meshcore_host == ""
         transport = build_transport(cfg)
         assert isinstance(transport, MeshtasticTransport)
-
-    def test_explicit_meshtastic_returns_meshtastic_transport(self):
-        cfg = self._config_with("meshtastic")
-        transport = build_transport(cfg)
-        assert isinstance(transport, MeshtasticTransport)
-
-    def test_meshcore_returns_meshcore_transport(self):
-        # Phase 2: meshcore is now implemented; build_transport returns a
-        # MeshCoreTransport instance (MeshTransport subclass).
-        from meshai.transport.meshcore_transport import MeshCoreTransport
-        cfg = self._config_with("meshcore")
-        transport = build_transport(cfg)
-        assert isinstance(transport, MeshCoreTransport)
-        assert isinstance(transport, MeshTransport)
-
-    def test_both_returns_composite(self):
-        """Phase 4: transport='both' now returns a CompositeTransport (seam filled)."""
+        # Must NOT be a composite when MeshCore is not configured.
         from meshai.transport.composite_transport import CompositeTransport
-        cfg = self._config_with("both")
+        assert not isinstance(transport, CompositeTransport)
+
+    def test_meshcore_host_set_returns_composite(self):
+        """Non-empty meshcore_host → CompositeTransport with both children."""
+        from meshai.transport.composite_transport import CompositeTransport
+        from meshai.transport.meshcore_transport import MeshCoreTransport
+        cfg = self._config_with_meshcore("1.2.3.4")
         t = build_transport(cfg)
         assert isinstance(t, CompositeTransport)
         assert len(t.children) == 2
+        assert isinstance(t.children[0], MeshtasticTransport)
+        assert isinstance(t.children[1], MeshCoreTransport)
 
-    def test_unknown_transport_raises_value_error(self):
-        cfg = self._config_with("unknown_transport_xyz")
-        with pytest.raises(ValueError):
-            build_transport(cfg)
+    def test_whitespace_only_host_is_treated_as_blank(self):
+        """Whitespace-only meshcore_host is treated as blank → Meshtastic only."""
+        cfg = ConnectionConfig()
+        cfg.meshcore_host = "   "
+        transport = build_transport(cfg)
+        assert isinstance(transport, MeshtasticTransport)
+        from meshai.transport.composite_transport import CompositeTransport
+        assert not isinstance(transport, CompositeTransport)
+
+    def test_config_has_no_transport_field(self):
+        """ConnectionConfig must not have a transport attribute after the refactor."""
+        cfg = ConnectionConfig()
+        assert not hasattr(cfg, "transport"), (
+            "ConnectionConfig.transport was not removed; the refactor is incomplete."
+        )
+
+    def test_stray_transport_key_in_yaml_loads_without_error(self):
+        """A config dict with a stale 'transport' key must load cleanly."""
+        from meshai.config import _dict_to_dataclass, ConnectionConfig as CC
+        raw = {
+            "type": "tcp",
+            "tcp_host": "10.0.0.1",
+            "transport": "both",  # stale key — must be ignored
+            "meshcore_host": "192.168.1.253",
+        }
+        cfg = _dict_to_dataclass(CC, raw)
+        # The stale key must be silently dropped; no AttributeError.
+        assert not hasattr(cfg, "transport")
+        assert cfg.meshcore_host == "192.168.1.253"
+
+    def test_serialized_config_has_no_transport_field(self):
+        """_dataclass_to_dict must not emit a 'transport' key."""
+        from meshai.config import _dataclass_to_dict
+        cfg = ConnectionConfig()
+        d = _dataclass_to_dict(cfg)
+        assert "transport" not in d
 
 
 # ---------------------------------------------------------------------------

work/tests/test_uniform_sizing.py

@@ -89,17 +89,16 @@ from meshai.notifications.pipeline import build_pipeline           # noqa: E402
 # ---------------------------------------------------------------------------
 
 def _mt_config(**overrides):
-    """Return a ConnectionConfig wired for meshtastic (default)."""
-    cfg = ConnectionConfig(transport="meshtastic")
+    """Return a ConnectionConfig with no MeshCore host (Meshtastic-only)."""
+    cfg = ConnectionConfig()  # meshcore_host defaults to "" → Meshtastic only
     for k, v in overrides.items():
         setattr(cfg, k, v)
     return cfg
 
 
 def _mc_config(**overrides):
-    """Return a ConnectionConfig wired for meshcore."""
+    """Return a ConnectionConfig with meshcore_host set (activates MeshCore)."""
     cfg = ConnectionConfig(
-        transport="meshcore",
         meshcore_host="127.0.0.1",
         meshcore_port=5050,
     )
@@ -158,7 +157,7 @@ class TestTransportMaxChars:
         """Sanity: all transports + CompositeTransport report mesh_max_chars=140.
 
         This is the canonical single-budget guarantee: Meshtastic, MeshCore,
-        and the composite (transport=both) all resolve to the same constant.
+        and the composite (meshcore_host set) all resolve to the same constant.
         """
         from meshai.config import ConnectionConfig
         from meshai.transport.composite_transport import CompositeTransport
@@ -169,9 +168,8 @@ class TestTransportMaxChars:
         # MeshCore
         assert MeshCoreTransport(_mc_config()).max_chars == 140
 
-        # Composite (built via factory with transport="both")
+        # Composite — derived from meshcore_host being non-empty
         cfg_both = ConnectionConfig(
-            transport="both",
             type="tcp",
             tcp_host="127.0.0.1",
             tcp_port=4403,