Stop lovelace_gen from breaking all the yaml which is not in lovelace...

README.md

@@ -28,6 +28,13 @@ To rerender the frontend, use the Refresh option from the three-dots-menu in Lov
 
 ![refresh](https://user-images.githubusercontent.com/1299821/62565489-2e655780-b887-11e9-86a1-2de868a4dc7d.png)
 
+### Second of all
+
+Any yaml file that is to be processed with `lovelace_gen` *MUST* have the following as its first line:
+
+```yaml
+# lovelace_gen
+```
 
 ### Let's continue
 
@@ -125,6 +132,7 @@ cards:
 
 `button_card.yaml`
 ```yaml
+# lovelace_gen
 {% if entity.startswith("light") %}
 type: light
 {% else %}
@@ -168,6 +176,7 @@ This can also be used for pictures.
 ## Example
 `ui_lovelace.yaml`
 ```yaml
+# lovelace_gen
 resources:
   # When you regenerate, the browser cache for this file will be invalidated
   - url: !file /local/card-mod.js
@@ -180,6 +189,7 @@ views:
 
 `lovelace/my_cool_view.yaml`
 ```yaml
+# lovelace_gen
 {% set my_lights = ["light.bed_light", "light.kitchen_lights", "light.ceiling_lights"] %}
 title: My view
 cards:
@@ -214,6 +224,7 @@ cards:
 
 `lovelace/floorplan.yaml`
 ```yaml
+# lovelace_gen
 {% macro lamp(entity, x, y) -%}
 {% if lamps %}
 - type: state-icon

custom_components/lovelace_gen/__init__.py

@@ -3,6 +3,7 @@
 import json
 import io
 import time
+from collections import OrderedDict
 
 import jinja2
 
@@ -15,9 +16,18 @@
 
 def load_yaml(fname, args={}):
     try:
-        stream = io.StringIO(jinja.get_template(fname).render(args))
-        stream.name = fname
-        return loader.yaml.load(stream, Loader=loader.SafeLineLoader) or {}
+        ll_gen = False
+        with open(fname, encoding="utf-8") as f:
+            if f.readline().lower().startswith("# lovelace_gen"):
+                ll_gen = True
+
+        if ll_gen:
+            stream = io.StringIO(jinja.get_template(fname).render(args))
+            stream.name = fname
+            return loader.yaml.load(stream, Loader=loader.SafeLineLoader) or OrderedDict()
+        else:
+            with open(fname, encoding="utf-8") as config_file:
+                return loader.yaml.load(config_file, Loader=loader.SafeLineLoader) or OrderedDict()
     except loader.yaml.YAMLError as exc:
         _LOGGER.error(str(exc))
         raise HomeAssistantError(exc)