Quick and dirty wrapper for indexeddb using idb and io-ts

indexeddb.ts

import { Either } from 'fp-ts/lib/Either';
import { openDB } from 'idb';
import { array, Type } from 'io-ts';
import { from, Observable, of, throwError } from 'rxjs';
import { mergeMap } from 'rxjs/operators';

export const objectFactory = (
  name: string,
  keyPath: string,
  option: 'readonly' | 'readwrite' | 'versionchange' = 'readonly',
  db: string = 'MockDatabase',
  version: number = 1
) =>
  openDB(db, version, {
    upgrade: db => {
      if (!db.objectStoreNames.includes(name)) {
        console.log('Got a thing');
        db.createObjectStore(name, { keyPath });
      }
    },
  }).then(db => db.transaction([name], option).objectStore(name));

export const decode = <A, O = A>(codec: Type<A, O>) => (t: unknown) =>
  codec.decode(t);

export const fromPromiseEither = <E, T>(
  p: Promise<Either<E, T>>
): Observable<T> =>
  from(p).pipe(mergeMap(e => (e.isLeft() ? throwError(e.value) : of(e.value))));

interface StoreConfig<G> {
  name: string;
  codec: Type<G>;
  keyPath: string;
  db?: string;
  version?: number;
  options?: 'readonly' | 'readwrite' | 'versionchange';
}

export const objectStore = <T>(C: StoreConfig<T>) => {
  const store = () =>
    objectFactory(C.name, C.keyPath, C.options, C.db, C.version);
  const allCodec = array(C.codec);

  const decodeC = decode(C.codec);
  const decodeAllC = decode(allCodec);

  const get = (id: string | number) =>
    store()
      .then(os => os.get(id))
      .then(decodeC);

  const put = <T>(value: T, id?: string | number) =>
    store()
      .then(os => os.put(value, id))
      .then(t => get(t.toString()))
      .then(decodeC);

  const patch = <T>(value: Partial<T>, id: string | number) =>
    get(id)
      .then(v => put({ ...v, ...value }, id))
      .then(() => get(id))
      .then(decodeC);

  const remove = (id: string | number) => store().then(os => os.delete(id));

  const getAll = () =>
    store()
      .then(os => os.getAll())
      .then(decodeAllC);

  return {
    get,
    put,
    patch,
    remove,
    getAll,
  };
};