Keep API not-found and 401 responses usable behind Ingress and in the Web UI.

Return native JSON with the missing id in the message, clear stale sessions on
401, and document ingress-nginx annotations so branded HTML 404/405 pages do
not rewrite simulator bodies.

app/main.py

@@ -6,6 +6,9 @@ import asyncio
 from typing import cast
 
 from fastapi import FastAPI
+from fastapi.responses import JSONResponse
+from starlette.exceptions import HTTPException as StarletteHTTPException
+from starlette.requests import Request as StarletteRequest
 
 from app.api.errors import ApiError, api_error_handler, unhandled_exception_handler
 from app.api.middleware import HeadAsGetMiddleware, RequestContextMiddleware
@@ -30,6 +33,26 @@ from app.vsphere.soap.router import router as vsphere_soap_router
 from app.web.routes import router as web_router
 
 
+async def _json_http_exception_handler(
+    _request: StarletteRequest, exc: StarletteHTTPException
+) -> JSONResponse:
+    """Always return JSON for HTTP errors — never HTML error pages from the app."""
+
+    detail = exc.detail
+    if isinstance(detail, dict):
+        # VsphereError and similar already carry the product envelope in detail.
+        content: dict | list = {"detail": detail}
+    elif isinstance(detail, list):
+        content = {"detail": detail}
+    else:
+        content = {"detail": detail}
+    return JSONResponse(
+        status_code=exc.status_code,
+        content=content,
+        media_type="application/json",
+    )
+
+
 def create_app(
     settings: Settings | None = None,
     database_factory: DatabaseFactory = default_database_factory,
@@ -110,6 +133,7 @@ def create_app(
     app.add_middleware(VsphereVersionGateMiddleware)
     app.add_exception_handler(Exception, unhandled_exception_handler)
     app.add_exception_handler(ApiError, api_error_handler)
+    app.add_exception_handler(StarletteHTTPException, _json_http_exception_handler)
     # Native vSphere surface (survives contract hot-swap).
     from app.vsphere.soap.pbm import router as vsphere_pbm_router
 

app/vsphere/domain/inventory_ops.py

@@ -218,9 +218,7 @@ def _is_seed_host_or_named_vm(moid: str, obj: Any) -> bool:
 
 
 async def set_host_maintenance(database: Database, host: str, enabled: bool) -> dict[str, Any]:
-    obj = await inventory.get_object(database, host)
-    if obj is None or obj.type != "HostSystem":
-        raise not_found(f"Host {host} not found")
+    obj = await inventory.require_object(database, host, type_name="HostSystem", resource="host")
     props = dict(obj.props)
     props["connection_state"] = "CONNECTED"
     props["maintenance_mode"] = enabled

app/vsphere/domain/vm_ops.py

@@ -14,10 +14,7 @@ from app.vsphere.errors import invalid_argument, not_found
 
 
 async def require_vm(database: Database, vm: str) -> inventory.ManagedObject:
-    obj = await inventory.get_object(database, vm)
-    if obj is None or obj.type != "VirtualMachine":
-        raise not_found(f"VM {vm} not found")
-    return obj
+    return await inventory.require_object(database, vm, type_name="VirtualMachine", resource="vm")
 
 
 def _default_identity(name: str, moid: str) -> dict[str, str]:

app/vsphere/errors.py

@@ -41,16 +41,38 @@ def unauthenticated(message: str = "Authentication required") -> VsphereError:
     )
 
 
-def not_found(message: str = "Not found") -> VsphereError:
+def not_found(message: str = "Not found", *, args: list[Any] | None = None) -> VsphereError:
     return VsphereError(
         404,
         error_type="not_found",
         messages=[
-            {"default_message": message, "id": "com.vmware.vapi.std.errors.not_found", "args": []}
+            {
+                "default_message": message,
+                "id": "com.vmware.vapi.std.errors.not_found",
+                "args": list(args or []),
+            }
         ],
     )
 
 
+def no_such(resource: str, resource_id: str) -> VsphereError:
+    """Native not-found with the missing id in the message (Ingress-friendly JSON)."""
+
+    message = f"No such {resource} ('{resource_id}')"
+    return VsphereError(
+        404,
+        error_type="not_found",
+        messages=[
+            {
+                "default_message": message,
+                "id": "com.vmware.vapi.std.errors.not_found",
+                "args": [resource_id],
+            }
+        ],
+        data={resource: message},
+    )
+
+
 def already_exists(message: str = "Already exists") -> VsphereError:
     return VsphereError(
         400,

app/vsphere/inventory.py

@@ -60,6 +60,36 @@ async def get_object(database: Database, moid: str) -> ManagedObject | None:
     return None if row is None else _row(row)
 
 
+_TYPE_RESOURCE: dict[str, str] = {
+    "HostSystem": "host",
+    "VirtualMachine": "vm",
+    "Datastore": "datastore",
+    "Datacenter": "datacenter",
+    "Folder": "folder",
+    "ClusterComputeResource": "cluster",
+    "ResourcePool": "resource_pool",
+    "Network": "network",
+}
+
+
+async def require_object(
+    database: Database,
+    moid: str,
+    *,
+    type_name: str | None = None,
+    resource: str | None = None,
+) -> ManagedObject:
+    """Return the managed object or raise a native not-found with the bad id."""
+
+    from app.vsphere.errors import no_such
+
+    obj = await get_object(database, moid)
+    label = resource or (type_name and _TYPE_RESOURCE.get(type_name)) or "object"
+    if obj is None or (type_name is not None and obj.type != type_name):
+        raise no_such(label, moid)
+    return obj
+
+
 async def upsert_object(
     database: Database,
     *,

app/vsphere/rest/platform_rest.py

@@ -464,9 +464,7 @@ async def host_storage(
     database: Database = Depends(get_database),
     _: SessionInfo = Depends(require_read),
 ) -> list[dict[str, Any]]:
-    obj = await inventory.get_object(database, host)
-    if obj is None or obj.type != "HostSystem":
-        raise not_found(f"Host {host} not found")
+    obj = await inventory.require_object(database, host, type_name="HostSystem", resource="host")
     devices = obj.props.get("storage_devices")
     return list(devices) if isinstance(devices, list) else []
 
@@ -477,9 +475,7 @@ async def host_networking(
     database: Database = Depends(get_database),
     _: SessionInfo = Depends(require_read),
 ) -> dict[str, Any]:
-    obj = await inventory.get_object(database, host)
-    if obj is None or obj.type != "HostSystem":
-        raise not_found(f"Host {host} not found")
+    obj = await inventory.require_object(database, host, type_name="HostSystem", resource="host")
     networking = obj.props.get("networking")
     return networking if isinstance(networking, dict) else {}
 
@@ -490,9 +486,7 @@ async def folder_children(
     database: Database = Depends(get_database),
     _: SessionInfo = Depends(require_read),
 ) -> list[dict[str, str]]:
-    parent = await inventory.get_object(database, folder)
-    if parent is None:
-        raise not_found(f"Folder {folder} not found")
+    await inventory.require_object(database, folder, resource="folder")
     children = [obj for obj in await inventory.list_objects(database) if obj.parent_moid == folder]
     return [{"moid": c.moid, "type": c.type, "name": c.name} for c in children]
 

app/vsphere/rest/router.py

@@ -12,7 +12,7 @@ from app.db.pool import Database
 from app.dependencies import get_database
 from app.vsphere import inventory
 from app.vsphere.domain import vm_ops
-from app.vsphere.errors import invalid_argument, not_found, unauthenticated
+from app.vsphere.errors import invalid_argument, unauthenticated
 from app.vsphere.rest import mappers
 from app.vsphere.security.authz import require_privilege, require_read
 from app.vsphere.security.session import (
@@ -200,9 +200,7 @@ async def get_vm(
     database: Database = Depends(get_database),
     _: SessionInfo = Depends(require_read),
 ) -> dict[str, Any]:
-    obj = await inventory.get_object(database, vm)
-    if obj is None or obj.type != "VirtualMachine":
-        raise not_found(f"VM {vm} not found")
+    obj = await inventory.require_object(database, vm, type_name="VirtualMachine", resource="vm")
     return mappers.vm_info(obj)
 
 
@@ -286,9 +284,7 @@ async def delete_vm(
     database: Database = Depends(get_database),
     _: SessionInfo = Depends(require_privilege("VirtualMachine.Inventory.Delete")),
 ) -> Response:
-    obj = await inventory.get_object(database, vm)
-    if obj is None or obj.type != "VirtualMachine":
-        raise not_found(f"VM {vm} not found")
+    obj = await inventory.require_object(database, vm, type_name="VirtualMachine", resource="vm")
     if obj.props.get("power_state") == "POWERED_ON":
         raise invalid_argument("VM must be powered off before delete")
     await inventory.delete_object(database, vm)
@@ -301,9 +297,7 @@ async def get_vm_power(
     database: Database = Depends(get_database),
     _: SessionInfo = Depends(require_read),
 ) -> dict[str, str]:
-    obj = await inventory.get_object(database, vm)
-    if obj is None or obj.type != "VirtualMachine":
-        raise not_found(f"VM {vm} not found")
+    obj = await inventory.require_object(database, vm, type_name="VirtualMachine", resource="vm")
     state = str(obj.props.get("power_state") or "POWERED_OFF")
     return {"state": state}
 
@@ -334,9 +328,7 @@ async def get_host(
     database: Database = Depends(get_database),
     _: SessionInfo = Depends(require_read),
 ) -> dict[str, Any]:
-    obj = await inventory.get_object(database, host)
-    if obj is None or obj.type != "HostSystem":
-        raise not_found(f"Host {host} not found")
+    obj = await inventory.require_object(database, host, type_name="HostSystem", resource="host")
     return mappers.host_info(obj)
 
 
@@ -355,9 +347,9 @@ async def get_datastore(
     database: Database = Depends(get_database),
     _: SessionInfo = Depends(require_read),
 ) -> dict[str, Any]:
-    obj = await inventory.get_object(database, datastore)
-    if obj is None or obj.type != "Datastore":
-        raise not_found(f"Datastore {datastore} not found")
+    obj = await inventory.require_object(
+        database, datastore, type_name="Datastore", resource="datastore"
+    )
     props = obj.props
     return {
         "name": obj.name,
@@ -421,9 +413,7 @@ async def vm_guest_identity(
     database: Database = Depends(get_database),
     _: SessionInfo = Depends(require_read),
 ) -> dict[str, Any]:
-    obj = await inventory.get_object(database, vm)
-    if obj is None or obj.type != "VirtualMachine":
-        raise not_found(f"VM {vm} not found")
+    obj = await inventory.require_object(database, vm, type_name="VirtualMachine", resource="vm")
     return {
         "name": obj.name,
         "family": "LINUX",

app/vsphere/rest/stub_surface.py

@@ -19,7 +19,6 @@ from app.dependencies import get_database
 from app.vsphere import inventory
 from app.vsphere.domain import api_state, tagging
 from app.vsphere.domain import content as content_domain
-from app.vsphere.errors import not_found
 from app.vsphere.rest.coverage import IMPLEMENTED
 from app.vsphere.security.authz import require_read
 from app.vsphere.security.session import SessionInfo
@@ -61,9 +60,7 @@ async def _live_get(database: Database, template: str, concrete: str) -> Any | N
 
     vm = params.get("vm")
     if vm and "/hardware/" in template:
-        obj = await inventory.get_object(database, vm)
-        if obj is None:
-            raise not_found(f"VM {vm} not found")
+        obj = await inventory.require_object(database, vm, type_name="VirtualMachine", resource="vm")
         props = obj.props or {}
 
         def _live_list(key: str) -> list[Any] | None:
@@ -107,9 +104,7 @@ async def _live_get(database: Database, template: str, concrete: str) -> Any | N
                     return nic
 
     if vm and "/guest/" in template:
-        obj = await inventory.get_object(database, vm)
-        if obj is None:
-            raise not_found(f"VM {vm} not found")
+        obj = await inventory.require_object(database, vm, type_name="VirtualMachine", resource="vm")
         props = obj.props or {}
         if template.endswith("/guest/local-filesystem"):
             if "guest_filesystems" in props:
@@ -130,15 +125,11 @@ async def _live_get(database: Database, template: str, concrete: str) -> Any | N
 
     host = params.get("host")
     if host and template.endswith("/networking"):
-        obj = await inventory.get_object(database, host)
-        if obj is None:
-            raise not_found(f"Host {host} not found")
+        obj = await inventory.require_object(database, host, type_name="HostSystem", resource="host")
         networking = (obj.props or {}).get("networking")
         return networking if networking is not None else None
     if host and "storage-device" in template:
-        obj = await inventory.get_object(database, host)
-        if obj is None:
-            raise not_found(f"Host {host} not found")
+        obj = await inventory.require_object(database, host, type_name="HostSystem", resource="host")
         devices = (obj.props or {}).get("storage_devices")
         return devices if devices is not None else None
 
@@ -156,9 +147,7 @@ async def _mutate_vm_hardware(
     vm = params.get("vm")
     if not vm or "/hardware/" not in template:
         return False
-    obj = await inventory.get_object(database, vm)
-    if obj is None:
-        raise not_found(f"VM {vm} not found")
+    obj = await inventory.require_object(database, vm, type_name="VirtualMachine", resource="vm")
     props = dict(obj.props or {})
 
     if verb == "POST" and template.endswith("/hardware/cdrom"):

app/web/index.html

@@ -6228,6 +6228,21 @@
       }
     }
 
+    async function clearSession(options = {}) {
+      const { toastMessage = null, toastKind = "info", closePanel = true } = options;
+      state.ticket = null;
+      state.csrf = null;
+      state.username = null;
+      document.cookie = "vmware-api-session-id=; Max-Age=0; path=/; SameSite=Strict";
+      try { localStorage.removeItem(LS_AUTH); } catch { /* ignore */ }
+      try { sessionStorage.removeItem(LS_AUTH); } catch { /* ignore */ }
+      setAuth(false);
+      persistAuth();
+      if (closePanel) closeAuthPanel();
+      resetClusterStats("—");
+      if (toastMessage) toast(toastMessage, toastKind);
+    }
+
     async function logout() {
       try {
         if (state.ticket) {
@@ -6240,15 +6255,15 @@
       } catch (error) {
         console.warn(error);
       }
-      state.ticket = null;
-      state.csrf = null;
-      state.username = null;
-      document.cookie = "vmware-api-session-id=; Max-Age=0; path=/; SameSite=Strict";
-      setAuth(false);
-      persistAuth();
-      closeAuthPanel();
-      resetClusterStats("—");
-      toast("Signed out", "info");
+      clearSession({ toastMessage: "Signed out", toastKind: "info" });
+    }
+
+    function expireSession() {
+      clearSession({
+        toastMessage: "Session expired — sign in again",
+        toastKind: "warn",
+        closePanel: false,
+      });
     }
 
     function updateStatusBadge(status) {
@@ -6340,6 +6355,9 @@
       const text = await res.text();
       let parsed;
       try { parsed = JSON.parse(text); } catch { parsed = text; }
+      if (res.status === 401 && (state.ticket || state.username)) {
+        expireSession();
+      }
       return { status: res.status, body: parsed, durationMs: Math.round(performance.now() - started) };
     }
 

docs/ru/troubleshooting.md

@@ -31,6 +31,60 @@ DB-backed стаб — 501 не должен появляться для изв
   base64 от `user:password`).
 - Отказ по правам — попробуйте сравнить `administrator@vsphere.local` и
   `readonly@vsphere.local` (см. [Авторизация](domains/authz.md)).
+- В Web UI ответ 401 очищает сохранённую сессию и переключает бейдж в шапке
+  на **Guest** с toast «Session expired — sign in again».
+
+## Ingress возвращает брендированный HTML 404 / nginx 405 вместо JSON
+
+Симулятор отвечает на API-ошибки JSON (`detail` / `error_type` /
+`messages`). Если вы видите HTML «page not found» сайта или голую страницу
+nginx **405**, **Ingress / reverse proxy** подменил тело upstream (часто через
+`custom-http-errors` у ingress-nginx).
+
+Исправьте аннотации Ingress для этого хоста (см.
+`helm/vmware-api-simulator/values-ingress-example.yaml`):
+
+```yaml
+annotations:
+  nginx.ingress.kubernetes.io/proxy-intercept-errors: "false"
+  nginx.ingress.kubernetes.io/custom-http-errors: "502,503"
+```
+
+Затем перепроверьте с `Accept: application/json`. Отсутствующий host должен
+выглядеть так:
+
+```json
+{
+  "detail": {
+    "error_type": "not_found",
+    "messages": [
+      {
+        "default_message": "No such host ('host-999')",
+        "id": "com.vmware.vapi.std.errors.not_found",
+        "args": ["host-999"]
+      }
+    ],
+    "data": { "host": "No such host ('host-999')" }
+  }
+}
+```
+
+Seeded id хостов для `small` / `large` / `big` начинаются с `host-11`.
+Cookbook-ВМ включают `vm-101` (`web-01`).
+
+### Корректная authenticated-мутация (vSphere Automation)
+
+Сессия в заголовке/cookie + JSON-тело (не form-urlencoded):
+
+```bash
+SID=$(curl -sk -u 'administrator@vsphere.local:VMware1!' -X POST \
+  "https://HOST/api/session" | tr -d '"')
+curl -sk -X POST "https://HOST/api/vcenter/vm" \
+  -H "Accept: application/json" \
+  -H "Content-Type: application/json" \
+  -H "vmware-api-session-id: $SID" \
+  -d '{"name":"lab-vm","guest_os":"OTHER_GUEST_64","placement":{"folder":"group-v23","host":"host-11","datastore":"datastore-31","resource_pool":"resgroup-22"}}'
+```
 
 ## Задача никогда не завершается
 

docs/troubleshooting.md

@@ -31,6 +31,59 @@ should not appear for a known path. If you see it:
   `user:password` base64).
 - Privilege denial — try `administrator@vsphere.local` vs
   `readonly@vsphere.local` to compare (see [Authorization](domains/authz.md)).
+- In the Web UI, a 401 clears the stored session and switches the header badge
+  to **Guest** with a “Session expired — sign in again” toast.
+
+## Ingress returns branded HTML 404 / nginx 405 instead of JSON
+
+The simulator answers API errors as JSON (`detail` / `error_type` /
+`messages`). If you see a site HTML “page not found” or plain nginx **405**
+page, the **Ingress / reverse proxy** replaced the upstream body (often via
+`custom-http-errors` on the ingress-nginx controller).
+
+Fix on the Ingress for this host (see
+`helm/vmware-api-simulator/values-ingress-example.yaml`):
+
+```yaml
+annotations:
+  nginx.ingress.kubernetes.io/proxy-intercept-errors: "false"
+  nginx.ingress.kubernetes.io/custom-http-errors: "502,503"
+```
+
+Then re-check with `Accept: application/json`. A missing host should look like:
+
+```json
+{
+  "detail": {
+    "error_type": "not_found",
+    "messages": [
+      {
+        "default_message": "No such host ('host-999')",
+        "id": "com.vmware.vapi.std.errors.not_found",
+        "args": ["host-999"]
+      }
+    ],
+    "data": { "host": "No such host ('host-999')" }
+  }
+}
+```
+
+Seeded host ids for `small` / `large` / `big` start at `host-11`. Cookbook VMs
+include `vm-101` (`web-01`).
+
+### Correct authenticated mutation (vSphere Automation)
+
+Session cookie/header + JSON body (not form-urlencoded):
+
+```bash
+SID=$(curl -sk -u 'administrator@vsphere.local:VMware1!' -X POST \
+  "https://HOST/api/session" | tr -d '"')
+curl -sk -X POST "https://HOST/api/vcenter/vm" \
+  -H "Accept: application/json" \
+  -H "Content-Type: application/json" \
+  -H "vmware-api-session-id: $SID" \
+  -d '{"name":"lab-vm","guest_os":"OTHER_GUEST_64","placement":{"folder":"group-v23","host":"host-11","datastore":"datastore-31","resource_pool":"resgroup-22"}}'
+```
 
 ## Task never finishes
 

helm/vmware-api-simulator/values-ingress-example.yaml

@@ -32,6 +32,13 @@ seed:
 ingress:
   enabled: true
   className: nginx
+  # Keep API JSON bodies (404/405/401). Cluster-wide custom-http-errors HTML
+  # pages must not rewrite simulator error responses.
+  annotations:
+    nginx.ingress.kubernetes.io/proxy-intercept-errors: "false"
+    # If the controller still injects branded HTML for 404/405, narrow or clear
+    # custom-http-errors on this Ingress (overrides controller defaults):
+    nginx.ingress.kubernetes.io/custom-http-errors: "502,503"
   hosts:
     - host: vmware-sim.example.com
       paths:

tests/unit/test_vsphere_errors.py

@@ -0,0 +1,22 @@
+"""vSphere not-found helpers expose the missing id in the message."""
+
+from __future__ import annotations
+
+from app.vsphere.errors import no_such, not_found
+
+
+def test_no_such_includes_resource_id() -> None:
+    error = no_such("host", "host-999")
+    assert error.status_code == 404
+    detail = error.detail
+    assert isinstance(detail, dict)
+    assert detail["error_type"] == "not_found"
+    message = detail["messages"][0]
+    assert message["default_message"] == "No such host ('host-999')"
+    assert message["args"] == ["host-999"]
+    assert detail["data"]["host"] == "No such host ('host-999')"
+
+
+def test_not_found_accepts_args() -> None:
+    error = not_found("Guest file not found: /tmp/x", args=["/tmp/x"])
+    assert error.detail["messages"][0]["args"] == ["/tmp/x"]