refactor: use constant volume path

crypt4gh_middleware/middleware.py

@@ -3,6 +3,7 @@
 
 import flask
 
+VOLUME_PATH = "/vol/crypt/"
 # mypy: disable-error-code="index"
 
 class PathNotAllowedException(ValueError):
@@ -26,30 +27,30 @@ def _add_decryption_executor(self, request: flask.Request) -> flask.Request:
                 "decrypt.py"
             ] + self.original_input_paths + [
                 "--output-dir",
-                "/vol/crypt/"
+                VOLUME_PATH
             ]
         }
         request.json["executors"].insert(0, executor)
         return request
 
     def _add_volume(self, request: flask.Request) -> flask.Request:
-        """Check volumes to ensure none start with /vol/crypt/ and add /vol/crypt/.
+        """Check volumes to ensure none start with VOLUME_PATH and add VOLUME_PATH.
 
         Raises:
-            PathNotAllowedError if volumes start with /vol/crypt/.
+            PathNotAllowedError if volumes start with VOLUME_PATH.
         """
         for volume in request.json["volumes"]:
-            if volume.startswith("/vol/crypt/"):
-                raise PathNotAllowedException("/vol/crypt/ is not allowed in volumes.")
-        request.json["volumes"].append("/vol/crypt/")
+            if volume.startswith(VOLUME_PATH):
+                raise PathNotAllowedException(f"{VOLUME_PATH} is not allowed in volumes.")
+        request.json["volumes"].append(VOLUME_PATH)
         return request
 
     def _change_executor_paths(self, request: flask.Request) -> flask.Request:
         """Change original input file paths in executors to the output directory."""
         for executor_body in request.json["executors"]:
             for i, path in enumerate(executor_body["command"]):
                 if path in self.original_input_paths:
-                    executor_body["command"][i] = str(Path("/vol/crypt")/Path(path).name)
+                    executor_body["command"][i] = str(Path(VOLUME_PATH)/Path(path).name)
         return request
 
     def _check_output_paths(self, request: flask.Request) -> None:
@@ -68,11 +69,11 @@ def _set_original_input_paths(self, request: flask.Request) -> None:
         """Retrieve and store the original input file paths.
         
         Raises:
-            PathNotAllowedError if any path starts with /vol/crypt/.
+            PathNotAllowedError if any path starts with VOLUME_PATH.
         """
         for input_body in request.json["inputs"]:
-            if input_body["path"].startswith("/vol/crypt/"):
-                raise PathNotAllowedException("/vol/crypt/ is not allowed in input path.")
+            if input_body["path"].startswith(VOLUME_PATH):
+                raise PathNotAllowedException(f"{VOLUME_PATH} is not allowed in input path.")
             self.original_input_paths.append(input_body["path"])
 
     def apply_middleware(self, request: flask.Request) -> flask.Request: