Function createDBGroupSlice

frontend/src/react/stores/app/dbGroup.ts:26–259

(set, get)

import { toError } from "./utils";

export const createDBGroupSlice: AppSliceCreator<DBGroupSlice> = (set, get) => {
  const unknownDatabaseGroup = createUnknownDatabaseGroup();

  // Immutable cache write. A name maps to a single group + the view it was
  // fetched with; overwriting is sufficient (no per-view keying needed). Also
  // clears any stale error so a successful (re)fetch doesn't leave a prior
  // failure visible to consumers reading `dbGroupErrorsByName`.
  const setCache = (group: DatabaseGroup, view: DatabaseGroupView) => {
    set((state) => ({
      dbGroupsByName: { ...state.dbGroupsByName, [group.name]: group },
      dbGroupViewByName: { ...state.dbGroupViewByName, [group.name]: view },
      dbGroupErrorsByName: {
        ...state.dbGroupErrorsByName,
        [group.name]: undefined,
      },
    }));
  };
  const removeCache = (name: string) => {
    set((state) => {
      const { [name]: _g, ...dbGroupsByName } = state.dbGroupsByName;
      const { [name]: _v, ...dbGroupViewByName } = state.dbGroupViewByName;
      return { dbGroupsByName, dbGroupViewByName };
    });
  };
  // Bulk variant of `setCache` — merges every group in one `set()` so a list
  // fetch notifies subscribers once instead of N times.
  const cacheGroups = (groups: DatabaseGroup[], view: DatabaseGroupView) => {
    set((state) => {
      const dbGroupsByName = { ...state.dbGroupsByName };
      const dbGroupViewByName = { ...state.dbGroupViewByName };
      for (const group of groups) {
        dbGroupsByName[group.name] = group;
        dbGroupViewByName[group.name] = view;
      }
      return { dbGroupsByName, dbGroupViewByName };
    });
  };

  return {
    dbGroupsByName: {},
    dbGroupViewByName: {},
    dbGroupRequests: {},
    dbGroupErrorsByName: {},

    fetchDBGroup: async (name, view = DatabaseGroupView.BASIC) => {
      if (!isValidDatabaseGroupName(name)) return undefined;
      const existing = get().dbGroupsByName[name];
      // A FULL request needs `matchedDatabases`; only reuse the cache when it
      // already holds the FULL view (a BASIC request is satisfied by either).
      if (
        existing &&
        (view !== DatabaseGroupView.FULL ||
          get().dbGroupViewByName[name] === DatabaseGroupView.FULL)
      ) {
        return existing;
      }
      const pending = get().dbGroupRequests[name];
      if (pending) return pending;