[app] Show error message on startup failure due to config load errors #241

Author: Breakthrough

docs/changelog.md

@@ -391,8 +391,9 @@ This version of DVR-Scan includes a new, faster background subtraction algorithm
 
 ### 1.8.2
 
- * [general] Minimum Python version is now 3.10 ([EOL](https://devguide.python.org/versions/))
- * [bugfix] Fix `quiet-mode` setting (`-q`/`--quiet` flag) still allowing extraneous output
- * [bugfix] Fix loading config from file in UI ([#253](https://github.com/Breakthrough/DVR-Scan/issues/253))
- * [bugfix] Fix scan error when enabling "Use PTS" input option with multiple videos ([#254](https://github.com/Breakthrough/DVR-Scan/issues/254))
+ * [general] Minimum supported Python version is now 3.10 (Python 3.9 is [EOL](https://devguide.python.org/versions/))
+ * [general] An error is now displayed when launching the app fails due to an invalid config file [#241](https://github.com/Breakthrough/DVR-Scan/issues/241)
+ * [bugfix] Fix `quiet-mode` setting (`-q`/`--quiet` flag) still allowing extraneous output [#243](https://github.com/Breakthrough/DVR-Scan/issues/243)
+ * [bugfix] Fix loading config from file in UI [#253](https://github.com/Breakthrough/DVR-Scan/issues/253)
+ * [bugfix] Fix scan error when enabling "Use PTS" input option with multiple videos [#254](https://github.com/Breakthrough/DVR-Scan/issues/254)
  * [bugfix] Fix unchecked UI options being turned on in config files [#256](https://github.com/Breakthrough/DVR-Scan/issues/256)

dvr_scan/__init__.py

@@ -35,7 +35,7 @@
 import sys
 
 # Used for module/distribution identification.
-__version__ = "1.9-dev0"
+__version__ = "1.8.2-dev0"
 
 # Handle loading OpenCV. This **MUST** be first before any other DVR-Scan or third-party
 # packages are imported which might attempt to import the `cv2` module.

dvr_scan/app/__main__.py

@@ -13,6 +13,8 @@
 import logging
 import sys
 from subprocess import CalledProcessError
+import tkinter
+import tkinter.messagebox
 
 from scenedetect import VideoOpenFailure
 
@@ -176,6 +178,11 @@ def main():
         logger.debug("Error loading config file:", exc_info=config_load_error)
         # Intentionally suppress the exception in release mode since we've already logged the
         # failure reason to the user above. We can now exit with an error code.
+        errors = [message for (severity, message) in init_log if severity >= logging.ERROR]
+        tkinter.messagebox.showerror(
+            title="DVR-Scan Startup Error",
+            message=f"Error loading config file. Reason:\n\n{'\n'.join(errors)}",
+        )
         raise SystemExit(1)
 
     show_traceback = getattr(logging, settings.get("verbosity").upper()) == logging.DEBUG