test: openapi assert version

python_client_generator/main.py

@@ -5,9 +5,8 @@
 
 from pathlib import Path
 
-from python_client_generator.utils import dereference_swagger
+from python_client_generator.utils import dereference_swagger, assert_openapi_version
 
-from .exceptions import UnsupportedOpenAPISpec
 from .generate_apis import generate_apis
 from .generate_base_client import generate_base_client
 from .generate_models import generate_models
@@ -31,10 +30,9 @@ def main() -> None:
 
     with open(args.open_api, "r") as f:
         swagger = json.load(f)
-    dereferenced_swagger = dereference_swagger(swagger, swagger)
 
-    if not dereferenced_swagger.get("components"):
-        raise UnsupportedOpenAPISpec("OpenAPI file provided is not version 3.x")
+    assert_openapi_version(swagger)
+    dereferenced_swagger = dereference_swagger(swagger, swagger)
 
     # Create root directory
     path = Path(args.outdir)

python_client_generator/utils.py

@@ -2,6 +2,10 @@
 
 from typing import Any, Dict, List
 
+import semver
+
+from python_client_generator.exceptions import UnsupportedOpenAPISpec
+
 
 def lookup_by_ref_parts(obj: Dict[str, Any], ref_parts: List[str]) -> Dict[str, Any]:
     child = obj[ref_parts[0]]
@@ -96,3 +100,8 @@ def resolve_type(schema: Dict[str, Any], depth: int = 0, use_literals: bool = Fa
         return "List[" + resolve_type(schema["items"], depth + 1) + "]"
 
     raise Exception("property: ", schema)
+
+
+def assert_openapi_version(schema: Dict[str, Any]) -> None:
+    if not schema.get("openapi") or semver.Version.parse(schema.get("openapi")).major != 3:
+        raise UnsupportedOpenAPISpec("OpenAPI file provided is not version 3.x")

tests/test_generator.py

@@ -1,14 +1,18 @@
 import filecmp
 import os
+from copy import deepcopy
 
 from pathlib import Path
 from typing import Any, Dict
 
+import pytest
+
+from python_client_generator.exceptions import UnsupportedOpenAPISpec
 from python_client_generator.generate_apis import generate_apis
 from python_client_generator.generate_base_client import generate_base_client
 from python_client_generator.generate_models import generate_models
 from python_client_generator.generate_pyproject import generate_pyproject
-
+from python_client_generator.utils import assert_openapi_version
 
 EXPECTED_PATH = Path(os.path.dirname(os.path.realpath(__file__))) / "expected"
 
@@ -37,3 +41,10 @@ def test_pyproject(openapi: Dict[str, Any], tmp_path: Path) -> None:
         filecmp.cmp(EXPECTED_PATH / "pyproject.toml", tmp_path / "pyproject.toml", shallow=False)
         is True
     )
+
+
+def test_assert_openapi_version(openapi: Dict[str, Any]) -> None:
+    openapi_copy = deepcopy(openapi)
+    openapi_copy["openapi"] = "2.0.0"
+    with pytest.raises(UnsupportedOpenAPISpec):
+        assert_openapi_version(openapi_copy)