keep Frigate+ model references when saving the models section

`/api/config` served a Frigate+ model's path as the resolved `/config/model_cache/<id>` file, and since the models list is saved whole, editing any model in the settings UI wrote that cache path back to the config in place of `plus://<id>`. After a restart the model loaded as a custom model with the default labelmap. The config API now reports the `plus://<id>` reference the model was configured with, and the models section drops the fields the Frigate+ model info supplies (size, tensor, pixel format, dtype, and type) instead of pinning them in the config.

frigate/api/app.py

@@ -393,6 +393,11 @@ def config(request: Request):
         model_dict["non_logo_attributes"] = model.non_logo_attributes
         model_dict["labelmap"] = model.merged_labelmap
 
+        # report the configured reference rather than the resolved cache path,
+        # so saving the config back doesn't lose the Frigate+ model
+        if model.plus_id:
+            model_dict["path"] = f"plus://{model.plus_id}"
+
         if not config["plus"]["enabled"]:
             continue
 

frigate/detectors/detector_config.py

@@ -123,6 +123,7 @@ class ModelConfig(BaseModel):
     _all_attributes: list[str] = PrivateAttr()
     _all_attribute_logos: list[str] = PrivateAttr()
     _model_hash: str = PrivateAttr()
+    _plus_id: str | None = PrivateAttr(default=None)
 
     @property
     def merged_labelmap(self) -> dict[int, str]:
@@ -148,6 +149,11 @@ class ModelConfig(BaseModel):
     def model_hash(self) -> str:
         return self._model_hash
 
+    @property
+    def plus_id(self) -> str | None:
+        """The Frigate+ model id, once a plus:// path has been resolved."""
+        return self._plus_id
+
     def __init__(self, **config):
         super().__init__(**config)
 
@@ -178,6 +184,7 @@ class ModelConfig(BaseModel):
         os.makedirs(MODEL_CACHE_DIR, exist_ok=True)
 
         model_id = self.path[7:]
+        self._plus_id = model_id
         self.path = os.path.join(MODEL_CACHE_DIR, model_id)
         model_info_path = f"{self.path}.json"
 

frigate/test/http_api/test_http_app.py

@@ -1,8 +1,10 @@
+import json
+import os
 from unittest.mock import Mock, patch
 
 import frigate.genai
 from frigate.config import GenAIProviderEnum
-from frigate.const import REDACTED_CREDENTIAL_SENTINEL
+from frigate.const import MODEL_CACHE_DIR, REDACTED_CREDENTIAL_SENTINEL
 from frigate.genai import GenAIClient
 from frigate.models import Event, Recordings, ReviewSegment
 from frigate.stats.emitter import StatsEmitter
@@ -90,6 +92,44 @@ class TestHttpApp(BaseTestHttp):
             mqtt = response.json()["mqtt"]
             assert mqtt["password"] == REDACTED_CREDENTIAL_SENTINEL
 
+    def test_config_response_keeps_plus_model_reference(self):
+        model_id = "test_plus_reference"
+        model_path = os.path.join(MODEL_CACHE_DIR, model_id)
+        os.makedirs(MODEL_CACHE_DIR, exist_ok=True)
+
+        with open(model_path, "w") as f:
+            f.write("model")
+
+        with open(f"{model_path}.json", "w") as f:
+            json.dump(
+                {
+                    "id": model_id,
+                    "type": "ssd",
+                    "supportedDetectors": ["cpu"],
+                    "width": 320,
+                    "height": 320,
+                    "inputShape": "nhwc",
+                    "pixelFormat": "rgb",
+                    "labelMap": {"0": "person"},
+                },
+                f,
+            )
+
+        self.addCleanup(os.remove, model_path)
+        self.addCleanup(os.remove, f"{model_path}.json")
+        self.minimal_config["models"] = [
+            {"path": f"plus://{model_id}", "devices": ["cpu"]}
+        ]
+        app = super().create_app()
+
+        with AuthTestClient(app) as client:
+            response = client.get("/config")
+            assert response.status_code == 200
+            assert response.json()["models"][0]["path"] == f"plus://{model_id}"
+
+        # detection still loads the resolved cache file
+        assert app.frigate_config.models[0].path == model_path
+
     ####################################################################################################################
     ###################################  POST /genai/probe Endpoint   ##################################################
     ####################################################################################################################

web/src/components/config-form/sections/section-special-cases.ts

@@ -7,6 +7,7 @@
  */
 
 import { RJSFSchema } from "@rjsf/utils";
+import { omit } from "lodash";
 import { applySchemaDefaults } from "@/lib/config-schema";
 import { isJsonObject } from "@/lib/utils";
 import { HiddenFieldContext, JsonObject, JsonValue } from "@/types/configForm";
@@ -352,6 +353,17 @@ export function synthesizeMissingFilters(
   return { ...(data as JsonObject), filters: newFilters };
 }
 
+// the backend fills these from the Frigate+ model info when it loads a
+// plus:// model, so saving them would only pin values Frigate+ owns
+const PLUS_SUPPLIED_MODEL_FIELDS = [
+  "width",
+  "height",
+  "input_tensor",
+  "input_pixel_format",
+  "input_dtype",
+  "model_type",
+];
+
 /**
  * Sanitize overrides payloads for section-specific quirks.
  */
@@ -360,6 +372,21 @@ export function sanitizeOverridesForSection(
   level: string,
   overrides: unknown,
 ): unknown {
+  // the models list is saved whole
+  if (sectionPath === "models" && Array.isArray(overrides)) {
+    return overrides.map((model) => {
+      if (
+        !isJsonObject(model) ||
+        typeof model.path !== "string" ||
+        !model.path.startsWith("plus://")
+      ) {
+        return model;
+      }
+
+      return omit(model, PLUS_SUPPLIED_MODEL_FIELDS);
+    });
+  }
+
   if (!overrides || !isJsonObject(overrides)) {
     return overrides;
   }

web/src/components/config-form/theme/fields/ModelSourcePicker.tsx

@@ -38,9 +38,7 @@ function plusModelId(path: unknown): string | undefined {
 
 type ModelSourcePickerProps = {
   path: unknown;
-  // Frigate+ metadata the backend attaches to a saved model, and the only
-  // reliable signal that one is active: it resolves `plus://<id>` to a local
-  // cache path before serving the config back
+  // Frigate+ metadata the backend attaches to a saved model
   plus?: { id: string } | null;
   // the detector this model runs on, used to filter incompatible Plus models
   detector?: string;