diff --git a/codegenerator/openapi/base.py b/codegenerator/openapi/base.py
index bb7b249..0ed7de2 100644
--- a/codegenerator/openapi/base.py
+++ b/codegenerator/openapi/base.py
@@ -16,7 +16,6 @@ import datetime
 import enum
 import importlib
 import inspect
-import itertools
 import jsonref
 import logging
 from pathlib import Path
@@ -48,6 +47,25 @@ class Unset:
         return False
 
 
+class QueryParamsSchema:
+    schema: dict[Any, Any] | None = None
+    min_version: str | None = None
+    max_version: str | None = None
+
+    def __init__(
+        self,
+        schema: dict[Any, Any] | None,
+        min_version: str | None,
+        max_version: str | None,
+    ):
+        self.schema = schema
+        self.min_version = min_version
+        self.max_version = max_version
+
+    def __hash(self):
+        return hash((self.min_version, self.max_version))
+
+
 UNSET: Unset = Unset()
 
 
@@ -464,6 +482,7 @@ class OpenStackServerSourceBase:
                 )
         elif action and hasattr(contr, action):
             # Normal REST operation without version bounds
+            (start_version, end_version) = (None, None)
             func = getattr(contr, action)
 
             # Get the path/op spec only when we have
@@ -477,6 +496,11 @@ class OpenStackServerSourceBase:
             operation_spec.tags.extend(operation_tags)
             operation_spec.tags = list(set(operation_spec.tags))
 
+            closure_vars = inspect.getclosurevars(func)
+            if closure_vars and closure_vars.nonlocals:
+                start_version = closure_vars.nonlocals.get("min_version")
+                end_version = closure_vars.nonlocals.get("max_version")
+
             self.process_operation(
                 func,
                 openapi_spec,
@@ -486,6 +510,8 @@ class OpenStackServerSourceBase:
                 operation_name=action,
                 method=method,
                 path=path,
+                start_version=start_version,
+                end_version=end_version,
             )
         elif action != "action" and action in controller_actions:
             # Normal REST operation without version bounds and present in
@@ -718,8 +744,8 @@ class OpenStackServerSourceBase:
             )
 
         action_name = None
-        query_params_versions = []
-        body_schemas: list[str | None] | Unset = UNSET
+        query_params_versions: set[QueryParamsSchema] = set()
+        body_schemas: set[str | None] | Unset = UNSET
         expected_errors = ["404"]
         response_code = None
         # Version bound on an operation are set only when it is not an
@@ -813,9 +839,9 @@ class OpenStackServerSourceBase:
                     schema_name, TypeSchema(**body_schema)
                 )
                 if body_schemas is UNSET:
-                    body_schemas = []
-                if isinstance(body_schemas, list):
-                    body_schemas.append(f"#/components/schemas/{schema_name}")
+                    body_schemas = set()
+                if isinstance(body_schemas, set):
+                    body_schemas.add(f"#/components/schemas/{schema_name}")
             rsp_spec = getattr(fdef, "return_type", None)
             if rsp_spec:
                 ser_schema = _convert_wsme_to_jsonschema(rsp_spec)
@@ -839,18 +865,20 @@ class OpenStackServerSourceBase:
             so = sorted(
                 query_params_versions,
                 key=lambda d: (
-                    tuple(map(int, d[1].split("."))) if d[1] else (0, 0)
+                    tuple(map(int, d.min_version.split(".")))
+                    if d.min_version
+                    else (0, 0)
                 ),
             )
-            for data, min_ver, max_ver in so:
-                if data:
+            for item in so:
+                if item.schema:
                     self.process_query_parameters(
                         openapi_spec,
                         operation_spec,
                         path_resource_names,
-                        data,
-                        min_ver,
-                        max_ver,
+                        item.schema,
+                        item.min_version,
+                        item.max_version,
                     )
         # if body_schemas or mode == "action":
         if method in ["PUT", "POST", "PATCH"]:
@@ -1070,7 +1098,7 @@ class OpenStackServerSourceBase:
                     schema_ref = f"#/components/schemas/{cont_schema_name}"
                 else:
                     # otherwise just use schema as body
-                    schema_ref = body_schemas[0]
+                    schema_ref = body_schemas.pop()
         elif body_schemas is not UNSET and len(body_schemas) > 1:
             # We may end up here multiple times if we have versioned operation. In this case merge to what we have already
             op_body = operation_spec.requestBody.setdefault("content", {})
@@ -1198,11 +1226,19 @@ class OpenStackServerSourceBase:
         ]:
             if not schema.openstack:
                 schema.openstack = {}
-            schema.openstack["min-ver"] = start_version.get_string()
+            schema.openstack["min-ver"] = (
+                start_version.get_string()
+                if hasattr(start_version, "get_string")
+                else start_version
+            )
         if end_version and self._api_ver_major(end_version) not in ["0", 0]:
             if not schema.openstack:
                 schema.openstack = {}
-            schema.openstack["max-ver"] = end_version.get_string()
+            schema.openstack["max-ver"] = (
+                end_version.get_string()
+                if hasattr(end_version, "get_string")
+                else end_version
+            )
         return schema
 
     def _get_param_ref(
@@ -1341,32 +1377,48 @@ class OpenStackServerSourceBase:
         end_version,
         action_name: str | None = None,
         operation_name: str | None = None,
-    ):
+    ) -> tuple[
+        set[QueryParamsSchema],
+        set[str | None] | Unset,
+        dict | Unset | None,
+        list[str],
+    ]:
         """Extract schemas from the decorated method."""
         # Unwrap operation decorators to access all properties
         expected_errors: list[str] = []
-        body_schemas: list[str | None] | Unset = UNSET
-        query_params_versions: list[tuple] = []
+        body_schemas: set[str | None] | Unset = UNSET
+        query_params_versions: set[QueryParamsSchema] = set()
         response_body_schema: dict | Unset | None = UNSET
 
         f = func
         while hasattr(f, "__wrapped__"):
             closure = inspect.getclosurevars(f)
             closure_locals = closure.nonlocals
-            min_ver = closure_locals.get("min_version", start_version)
+            min_ver = (
+                closure_locals.get("min_version", start_version)
+                or start_version
+            )
+
             if min_ver and not isinstance(min_ver, str):
                 min_ver = (
                     min_ver.get_string()
                     if hasattr(min_ver, "get_string")
                     else str(min_ver)
                 )
-            max_ver = closure_locals.get("max_version", end_version)
+            if min_ver and not start_version:
+                start_version = min_ver
+
+            max_ver = (
+                closure_locals.get("max_version", end_version) or end_version
+            )
             if max_ver and not isinstance(max_ver, str):
                 max_ver = (
                     max_ver.get_string()
                     if hasattr(max_ver, "get_string")
                     else str(max_ver)
                 )
+            if max_ver and not end_version:
+                end_version = max_ver
 
             if "errors" in closure_locals:
                 expected_errors = closure_locals["errors"]
@@ -1389,11 +1441,12 @@ class OpenStackServerSourceBase:
                 )
                 # body schemas are not UNSET anymore
                 if body_schemas is UNSET:
-                    body_schemas = []
+                    body_schemas = set()
                 if obj is not None:
                     if obj.get("type") in ["object", "array"]:
                         # We only allow object and array bodies
-                        # To prevent type name collision keep module name part of the name
+                        # To prevent type name collision keep module name
+                        # part of the name
                         typ_name = (
                             "".join([x.title() for x in path_resource_names])
                             + func.__name__.title()
@@ -1428,12 +1481,12 @@ class OpenStackServerSourceBase:
                             comp_schema.openstack["action-name"] = action_name
 
                         ref_name = f"#/components/schemas/{typ_name}"
-                        if isinstance(body_schemas, list):
-                            body_schemas.append(ref_name)
+                        if isinstance(body_schemas, set):
+                            body_schemas.add(ref_name)
                 else:
                     # register no-body
-                    if isinstance(body_schemas, list):
-                        body_schemas.append(None)
+                    if isinstance(body_schemas, set):
+                        body_schemas.add(None)
 
             if "response_body_schema" in closure_locals or hasattr(
                 f, "_response_body_schema"
@@ -1451,17 +1504,21 @@ class OpenStackServerSourceBase:
                     "query_params_schema",
                     getattr(f, "_request_query_schema", {}),
                 )
-                query_params_versions.append((obj, min_ver, max_ver))
+                query_params_versions.add(
+                    QueryParamsSchema(obj, min_ver, max_ver)
+                )
             elif "request_query_schema" in closure_locals:
                 # Nova altered the decorator
                 obj = closure_locals.get(
                     "request_query_schema",
                     getattr(f, "request_query_schema", {}),
                 )
-                query_params_versions.append((obj, min_ver, max_ver))
+                query_params_versions.add(
+                    QueryParamsSchema(obj, min_ver, max_ver)
+                )
             if "validators" in closure_locals:
                 validators = closure_locals.get("validators")
-                body_schemas = []
+                body_schemas = set()
                 if isinstance(validators, dict):
                     for k, v in validators.items():
                         sig = inspect.signature(v)
@@ -1498,8 +1555,9 @@ class OpenStackServerSourceBase:
                                 )
 
                                 ref_name = f"#/components/schemas/{typ_name}"
-                                if isinstance(body_schemas, list):
-                                    body_schemas.append(ref_name)
+
+                                if isinstance(body_schemas, set):
+                                    body_schemas.add(ref_name)
 
             f = f.__wrapped__
 
diff --git a/codegenerator/openapi/cinder.py b/codegenerator/openapi/cinder.py
index bad289e..08351b8 100644
--- a/codegenerator/openapi/cinder.py
+++ b/codegenerator/openapi/cinder.py
@@ -66,13 +66,22 @@ class CinderV3Generator(OpenStackServerSourceBase):
     ]
 
     def _api_ver_major(self, ver):
-        return ver._ver_major
+        if hasattr(ver, "_ver_major"):
+            return ver._ver_major
+        elif isinstance(ver, str) and "." in ver:
+            return ver.split(".")[0]
 
     def _api_ver_minor(self, ver):
-        return ver._ver_minor
+        if hasattr(ver, "_ver_minor"):
+            return ver._ver_minor
+        elif isinstance(ver, str) and "." in ver:
+            return ver.split(".")[1]
 
     def _api_ver(self, ver):
-        return (ver._ver_major, ver._ver_minor)
+        if hasattr(ver, "_ver_major") and hasattr(ver, "_ver_minor"):
+            return (ver._ver_major, ver._ver_minor)
+        elif isinstance(ver, str):
+            return tuple(int(x) for x in ver.split("."))
 
     def generate(self, target_dir, args):
         proc = Process(target=self._generate, args=[target_dir, args])
diff --git a/codegenerator/openapi/keystone.py b/codegenerator/openapi/keystone.py
index 866c619..63243f4 100644
--- a/codegenerator/openapi/keystone.py
+++ b/codegenerator/openapi/keystone.py
@@ -22,6 +22,8 @@ from codegenerator.common.schema import PathSchema
 from codegenerator.common.schema import SpecSchema
 from codegenerator.common.schema import TypeSchema
 from codegenerator.openapi.base import OpenStackServerSourceBase
+from codegenerator.openapi.base import QueryParamsSchema
+from codegenerator.openapi.base import Unset
 from codegenerator.openapi.keystone_schemas import application_credential
 from codegenerator.openapi.keystone_schemas import auth
 from codegenerator.openapi.keystone_schemas import common
@@ -378,13 +380,13 @@ class KeystoneGenerator(OpenStackServerSourceBase):
             doc = rst_to_md(doc)
             operation_spec.description = LiteralScalarString(doc)
 
-        query_params_versions = []
-        body_schemas = []
+        query_params_versions: set[QueryParamsSchema] = set()
+        body_schemas: set[str | None] | Unset | None = set()
         expected_errors = ["404"]
         response_code = None
         start_version = None
         end_version = None
-        ser_schema: dict | None = {}
+        ser_schema: dict | None | Unset = {}
 
         (query_params_versions, body_schemas, ser_schema, expected_errors) = (
             self._process_decorators(
@@ -403,18 +405,20 @@ class KeystoneGenerator(OpenStackServerSourceBase):
             so = sorted(
                 query_params_versions,
                 key=lambda d: (
-                    tuple(map(int, d[1].split("."))) if d[1] else (0, 0)
+                    tuple(map(int, d.min_version.split(".")))
+                    if d.min_version
+                    else (0, 0)
                 ),
             )
-            for data, min_ver, max_ver in so:
-                if data:
+            for item in so:
+                if item.schema:
                     self.process_query_parameters(
                         openapi_spec,
                         operation_spec,
                         path_resource_names,
-                        data,
-                        min_ver,
-                        max_ver,
+                        item.schema,
+                        item.min_version,
+                        item.max_version,
                     )
 
         if method in ["PUT", "POST", "PATCH"]:
diff --git a/codegenerator/openapi/nova.py b/codegenerator/openapi/nova.py
index 85b71c7..3e3e3a4 100644
--- a/codegenerator/openapi/nova.py
+++ b/codegenerator/openapi/nova.py
@@ -38,13 +38,22 @@ class NovaGenerator(OpenStackServerSourceBase):
     }
 
     def _api_ver_major(self, ver):
-        return ver.ver_major
+        if hasattr(ver, "ver_major"):
+            return ver.ver_major
+        elif isinstance(ver, str) and "." in ver:
+            return ver.split(".")[0]
 
     def _api_ver_minor(self, ver):
-        return ver.ver_minor
+        if hasattr(ver, "ver_minor"):
+            return ver.ver_minor
+        elif isinstance(ver, str) and "." in ver:
+            return ver.split(".")[1]
 
     def _api_ver(self, ver):
-        return (ver.ver_major, ver.ver_minor)
+        if hasattr(ver, "ver_major") and hasattr(ver, "ver_minor"):
+            return (ver.ver_major, ver.ver_minor)
+        elif isinstance(ver, str):
+            return tuple(int(x) for x in ver.split("."))
 
     def _generate(self, target_dir, args):
         from nova.api.openstack import api_version_request
diff --git a/codegenerator/openapi/octavia.py b/codegenerator/openapi/octavia.py
index b959447..6f188b7 100644
--- a/codegenerator/openapi/octavia.py
+++ b/codegenerator/openapi/octavia.py
@@ -20,10 +20,9 @@ import fixtures
 
 from codegenerator.common.schema import SpecSchema
 from codegenerator.common.schema import TypeSchema
-from codegenerator.openapi.base import (
-    OpenStackServerSourceBase,
-    _convert_wsme_to_jsonschema,
-)
+from codegenerator.openapi.base import _convert_wsme_to_jsonschema
+from codegenerator.openapi.base import OpenStackServerSourceBase
+from codegenerator.openapi.base import QueryParamsSchema
 from codegenerator.openapi.utils import merge_api_ref_doc
 
 from ruamel.yaml.scalarstring import LiteralScalarString
@@ -1177,7 +1176,7 @@ class OctaviaGenerator(OpenStackServerSourceBase):
             }
 
         if qp:
-            query_params_versions.append((qp, None, None))
+            query_params_versions.add(QueryParamsSchema(qp, None, None))
 
         return (
             query_params_versions,
diff --git a/zuul.d/project.yaml b/zuul.d/project.yaml
index 5f1fb92..59509cc 100644
--- a/zuul.d/project.yaml
+++ b/zuul.d/project.yaml
@@ -12,6 +12,7 @@
         - codegenerator-openapi-container-infrastructure-management-tips-with-api-ref
         - codegenerator-openapi-dns-tips-with-api-ref
         - codegenerator-openapi-identity-tips-with-api-ref
+        - codegenerator-openapi-identity-tips
         - codegenerator-openapi-image-tips-with-api-ref
         - codegenerator-openapi-key-manager-tips
         - codegenerator-openapi-load-balancing-tips-with-api-ref