Merge pull request #269 from Living-with-machines/dev_download

Check both upper and lower corners when finding tilesize

mapreader/download/tile_merging.py

@@ -123,7 +123,16 @@ def _load_tile_size(self, grid_bb: GridBoundingBox):
         tuple
             Size of tile
         """
-        start_image = self._load_image_to_grid_cell(grid_bb.lower_corner)
+        try:
+            start_image = self._load_image_to_grid_cell(grid_bb.lower_corner)
+        except FileNotFoundError:
+            logger.warning("Image has missing tiles in bottom left corner.")
+            try:
+                start_image = self._load_image_to_grid_cell(grid_bb.upper_corner)
+            except FileNotFoundError as err:
+                logger.warning("Image has missing tiles in upper right corner.")
+                raise FileNotFoundError("[ERROR] Image is missing tiles for both lower left and upper right corners.")
+
         img_size = start_image.size
         assert (
             img_size[0] == img_size[1]
@@ -169,7 +178,7 @@ def merge(self, grid_bb: GridBoundingBox, file_name: Union[str, None] = None) ->
             try:
                 current_tile = Image.open(self._generate_tile_name(current_cell))
                 merged_image.paste(current_tile, (tile_size * i, tile_size * j))
-            except:
+            except FileNotFoundError:
                 logger.info(f"Cannot find tile with grid_index = {current_cell}")
 
         logger.info("Writing file..")