inspector/core/react/usePagedPrompts.ts
cliffhall de60983ccc fix: surface list-fetch failures in paginated mode (#1998)
#1954 wired the list-load error off the aggregate managed stores only.
With `paginatedLists` on, those stores deliberately skip their all-page
walk, so their error is permanently null — while the paged stores that
actually drive the sidebar had no error state at all and `loadPage` had
a try/finally with no catch. A failing list showed an empty panel with
no alert and no Retry, and the connect-time `void loadPage(undefined)`
left an unhandled rejection.

- Give PagedTools/Prompts/ResourcesState observable error state: an
  `errorChange` event plus `getError()`, set in a new catch in
  `loadPage`, cleared on the next success and on disconnect. The
  rejection is still re-thrown, matching ManagedListState — callers'
  auth-recovery wrappers key off it to detect a 401.
- Catch the connect-time load's rejection (`.catch(() => {})`) now that
  the failure is recorded as state rather than lost.
- Select the error by mode in `usePaginatedList`, the same way `items`
  already is, and read it in App.tsx from the pagination model.
- Rename `useManagedListError` to `useListError`: both store families
  expose an identical `errorChange`, so the hook declares that one-event
  contract itself instead of importing ManagedListEventMap.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0177mPHAdECD18nLLCTwR5rh
Signed-off-by: cliffhall <cliff@futurescale.com>
2026-08-17 20:40:23 -04:00

102 lines
3.3 KiB
TypeScript

import { useState, useEffect, useCallback } from "react";
import type { InspectorClientProtocol } from "../mcp/inspectorClientProtocol.js";
import type {
PagedPromptsState,
PagedPromptsStateEventMap,
LoadPageResult,
} from "../mcp/state/pagedPromptsState.js";
import type { Prompt } from "@modelcontextprotocol/client";
import type { TypedEventGeneric } from "../mcp/typedEventTarget.js";
import { useListError } from "./useListError.js";
export interface UsePagedPromptsResult {
prompts: Prompt[];
/** The server's `nextCursor` from the last page (undefined = at the end). */
nextCursor?: string;
/** Pages loaded since the last reset (page 1 = 1). */
pageCount: number;
/**
* The last page load's failure, or `null` when it succeeded. In paginated
* mode this store is the display source, so this — not the managed
* store's error — is what the panel renders (#1998).
*/
error: Error | null;
loadPage: (
cursor?: string,
metadata?: Record<string, string>,
) => Promise<LoadPageResult>;
clear: () => void;
}
/**
* React hook that subscribes to PagedPromptsState and returns prompts +
* pagination progress + loadPage. The state store owns loading; this mirrors
* its observable state.
*/
export function usePagedPrompts(
client: InspectorClientProtocol | null,
pagedPromptsState: PagedPromptsState | null,
): UsePagedPromptsResult {
const [prompts, setPrompts] = useState<Prompt[]>(
pagedPromptsState?.getPrompts() ?? [],
);
const [nextCursor, setNextCursor] = useState<string | undefined>(
pagedPromptsState?.getPagination().nextCursor,
);
const [pageCount, setPageCount] = useState<number>(
pagedPromptsState?.getPagination().pageCount ?? 0,
);
useEffect(() => {
if (!pagedPromptsState) {
setPrompts([]);
setNextCursor(undefined);
setPageCount(0);
return;
}
setPrompts(pagedPromptsState.getPrompts());
setNextCursor(pagedPromptsState.getPagination().nextCursor);
setPageCount(pagedPromptsState.getPagination().pageCount);
const onPromptsChange = (
event: TypedEventGeneric<PagedPromptsStateEventMap, "promptsChange">,
) => {
setPrompts(event.detail);
};
const onPaginationChange = (
event: TypedEventGeneric<PagedPromptsStateEventMap, "paginationChange">,
) => {
setNextCursor(event.detail.nextCursor);
setPageCount(event.detail.pageCount);
};
pagedPromptsState.addEventListener("promptsChange", onPromptsChange);
pagedPromptsState.addEventListener("paginationChange", onPaginationChange);
return () => {
pagedPromptsState.removeEventListener("promptsChange", onPromptsChange);
pagedPromptsState.removeEventListener(
"paginationChange",
onPaginationChange,
);
};
}, [pagedPromptsState]);
const error = useListError(pagedPromptsState);
const loadPage = useCallback(
async (
cursor?: string,
metadata?: Record<string, string>,
): Promise<LoadPageResult> => {
if (!pagedPromptsState || !client) {
return { prompts: [], nextCursor: undefined };
}
return pagedPromptsState.loadPage(cursor, metadata);
},
[client, pagedPromptsState],
);
const clear = useCallback(() => {
pagedPromptsState?.clear();
}, [pagedPromptsState]);
return { prompts, nextCursor, pageCount, error, loadPage, clear };
}