Add annotation-reading code

CHANGES.md

@@ -6,6 +6,7 @@
   `s:softwareVersion` (#90)
 * Allow creation of EOAP-only and xcube-server-only images, omitting
   unnecessary dependencies (#56)
+* Add a utility function to read annotations from notebook code (#91)
 
 ## Changes in 0.1.2
 

test/test_parameters.py

@@ -377,3 +377,16 @@ def test_read_datasets_from_product_missing_items(
         params.read_datasets_from_product(tmp_path, {})
     for substring in "missing", "foo", "bar":
         assert substring in str(error)
+
+
+def test_read_annotations_from_code():
+    import textwrap
+
+    annotated_code = textwrap.dedent("""
+        my_int: int = 42
+        eoproduct: "EOInput" = None
+        """)
+    assert NotebookParameters.read_annotations(annotated_code) == {
+        "my_int": "int",
+        "eoproduct": "'EOInput'",
+    }

xcengine/parameters.py

@@ -234,3 +234,13 @@ def cwl_type(type_: type) -> str:
             }[type_]
         except KeyError:
             raise ValueError(f"Unhandled type {type_}")
+
+    @staticmethod
+    def read_annotations(code: str) -> dict[str, str]:
+        import ast
+
+        return {
+            ast.unparse(node.target): ast.unparse(node.annotation)
+            for node in ast.walk(ast.parse(code))
+            if isinstance(node, ast.AnnAssign)
+        }