Added yaml-root to convert_polygons.

Author: Eli

schimpy/convert_polygons.py

@@ -20,20 +20,29 @@
     type=click.Path(),
     help="Output file (YAML or Shapefile).",
 )
+@click.option(
+    "--yaml-root",
+    default=None,
+    type=str,
+    help="Dot-separated path to the parent of the polygons key in a nested YAML file, "
+    "e.g. --yaml-root=mesh.depth_enforcement. Only used with YAML input.",
+)
 @click.help_option("-h", "--help")
-def convert_polygons_cli(input, output):
+def convert_polygons_cli(input, output, yaml_root):
     """CLI wrapper for converting polygon files."""
-    convert_polys(input, output)
+    convert_polys(input, output, yaml_root=yaml_root)
 
 
-def convert_polys(input, output):
+def convert_polys(input, output, yaml_root=None):
     if input.endswith(".yaml"):
-        polygons = read_polygons(input)
+        polygons = read_polygons(input, yaml_root=yaml_root)
         if output.endswith(".shp"):
             write_polygons(output, polygons)
         else:
             raise ValueError("Not supported output file type")
     elif input.endswith(".shp"):
+        if yaml_root is not None:
+            raise ValueError("--yaml-root is only supported with YAML input files.")
         polygons = read_polygons(input)
         write_polygons(output, polygons)
     else:

schimpy/schism_polygon.py

@@ -156,10 +156,17 @@ def read(self, data):
 class SchismPolygonYamlReader(SchismPolygonIo):
     """Read polygons from a SCHISM YAML polygon file"""
 
-    def read(self, fpath):
+    def read(self, fpath, yaml_root=None):
         if os.path.exists(fpath):
             with open(fpath, "r") as f_in:
                 raw = schism_yaml.load_raw(f_in)
+                if yaml_root is not None:
+                    for key in yaml_root.split("."):
+                        if not isinstance(raw, dict) or key not in raw:
+                            raise ValueError(
+                                f"yaml_root key '{key}' not found in YAML structure"
+                            )
+                        raw = raw[key]
                 return SchismPolygonDictConverter().read(raw)
         else:
             raise ValueError("File not found")
@@ -326,10 +333,19 @@ def get_writer(self, name):
             raise ValueError("Not in the SchismPolygonIoFactory")
 
 
-def read_polygons(fpath):
-    """Read a polygon file"""
+def read_polygons(fpath, yaml_root=None):
+    """Read a polygon file
+
+    Parameters
+    ----------
+    fpath : str
+        Path to the polygon file (YAML or Shapefile).
+    yaml_root : str, optional
+        Dot-separated path to navigate into a nested YAML structure
+        before reading polygons (e.g., 'mesh.depth_enforcement').
+    """
     if fpath.endswith(".yaml"):
-        return SchismPolygonIoFactory().get_reader("yaml").read(fpath)
+        return SchismPolygonIoFactory().get_reader("yaml").read(fpath, yaml_root=yaml_root)
     elif fpath.endswith(".shp"):
         return SchismPolygonIoFactory().get_reader("shp").read(fpath)
     else: