Updated spec_url to allow for file in root, without a path prefix, wh…

…en Configuration path set to None.

Also made spec_url more resilient to path and filename values with leading/trailing slashes.

spectree/config.py

@@ -1,3 +1,4 @@
+import posixpath
 import warnings
 from enum import Enum
 from typing import TYPE_CHECKING, Any, Dict, List, Mapping, Optional, Union
@@ -65,7 +66,7 @@ class Configuration(BaseSettings):
     license: Optional[License] = None
 
     # SpecTree configurations
-    #: OpenAPI doc route path prefix (i.e. /apidoc/)
+    #: OpenAPI doc route path prefix (i.e. /apidoc/) or empty string for no path prefix.
     path: str = "apidoc"
     #: OpenAPI file route path suffix (i.e. /apidoc/openapi.json)
     filename: str = "openapi.json"
@@ -117,7 +118,9 @@ def convert_to_lower_case(cls, values: Mapping[str, Any]) -> Dict[str, Any]:
 
     @property
     def spec_url(self) -> str:
-        return f"/{self.path}/{self.filename}"
+        sep = posixpath.sep
+        parts = (sep, self.path.lstrip(sep), self.filename.lstrip(sep))
+        return posixpath.join(*parts)
 
     def swagger_oauth2_config(self) -> Dict[str, str]:
         """

tests/test_config.py

@@ -60,6 +60,28 @@ def test_config_case():
     assert config.title == "Demo"
 
 
+@pytest.mark.parametrize("filename", ["openapi.json", "/openapi.json"])
+@pytest.mark.parametrize("path", ["", "/"])
+def test_config_spec_url_when_given_empty_path(path, filename):
+    """
+    Test spec_url given empty path values and filename values with and
+    without leading slash.
+    """
+    config = Configuration(path=path, filename=filename)
+    assert config.spec_url == "/openapi.json"
+
+
+@pytest.mark.parametrize("filename", ["openapi.json", "/openapi.json"])
+@pytest.mark.parametrize("path", ["prefix", "/prefix", "prefix/", "/prefix/"])
+def test_config_spec_url_when_given_path_and_filename(path, filename):
+    """
+    Test spec_url given path and filename values with and without
+    leading/trailing slashes.
+    """
+    config = Configuration(path=path, filename=filename)
+    assert config.spec_url == "/prefix/openapi.json"
+
+
 @pytest.mark.parametrize(("secure_item"), SECURITY_SCHEMAS)
 def test_update_security_scheme(secure_item: Type[SecurityScheme]):
     # update and validate each schema type