get attribute methods extension

modflowapi/modflowapi.py

@@ -1,3 +1,10 @@
+from ctypes import (
+    byref,
+    c_char_p,
+    c_int,
+    create_string_buffer,
+)
+from typing import Tuple
 from xmipy import XmiWrapper
 
 
@@ -25,3 +32,52 @@ def __init__(
             working_directory=working_directory,
             timing=timing,
         )
+
+    def get_attrs_item_count(self) -> int:
+        count = c_int(0)
+        self.execute_function(self.lib.get_attrs_item_count, byref(count))
+        return count.value
+
+    def get_attrs_keys(self) -> Tuple[str]:
+        len_attr_name = self.get_constant_int("BMI_LENATTRNAME")
+        nr_output_vars = self.get_attrs_item_count()
+        len_names = nr_output_vars * len_attr_name
+        names = create_string_buffer(len_names)
+
+        # get a (1-dim) char array (char*) containing the output variable
+        # names as \x00 terminated sub-strings
+        self.execute_function(self.lib.get_attrs_keys, byref(names))
+
+        # decode
+        output_vars = [
+            names[i * len_attr_name : (i + 1) * len_attr_name]
+            .split(b"\0", 1)[0]
+            .decode("ascii")
+            for i in range(nr_output_vars)
+        ]
+        return tuple(output_vars)
+
+    def get_var_attrs(self, name: str) -> Tuple[str]:
+        len_attr_name = self.get_constant_int("BMI_LENATTRNAME")
+        nr_output_vars = self.get_attrs_item_count()
+        len_attrs = nr_output_vars * len_attr_name
+        attrs = create_string_buffer(len_attrs)
+
+        # get a (1-dim) char array (char*) containing the output variable
+        # names as \x00 terminated sub-strings
+        self.execute_function(
+            self.lib.get_var_attrs,
+            c_char_p(name.encode()),
+            byref(attrs),
+            detail="for variable " + name
+        )
+
+        # decode
+        output_vars = [
+            attrs[i * len_attr_name : (i + 1) * len_attr_name]
+            .split(b"\0", 1)[0]
+            .decode("ascii")
+            for i in range(nr_output_vars)
+        ]
+
+        return tuple(output_vars)