IndexedDb helper library with RxJS based interface

[TapaiBalazs]

There are libraries out there that support putting values into IndexedDb, such as localforage but I think creating a library with an RxJS interface would be helpful.

My idea as an interface is something like the following:

const database$ = connectIndexedDb('databaseName')  // returns an Observable<IDBDatabase>
const store$ = database$.pipe(getObjectStore('storeName')) // returns an Observable<IDBObjectStore>

const keyValue$ = store$.pipe(
  createItem('key', 'value'), // returns an Observable<IDBObjectStore>,
  read('key') // returns an Observable that emits every time the value in that key changes (requires some internal scoping though)
)

const keys$ = store$.pipe(
  keys() // returns an Observable<IDBValidKey[]> that emits every time a new key is added or an existing one gets removed
)

const entries$ = store$.pipe(
  entries<any>() // returns an Observable<T> that emits every time a value changes
)

store$.pipe(updateItem('key', 'value2')).subscribe() // the keyValue$ and the entries$ observables will emit

store$.pipe(deleteItem('key')).subscribe() // the keyValue$, the keys$ and the entries$ observables will emit

// There should be an addItem('value') method as well for Object Stores that were created with autoIncrement

Now we are in a lucky position because most of this library could be tested in our demo app by switching the existing localforage implementation to our library and our cypress tests will deal with the rest.

We could also create a new example page where we would use an autoIncrement object store to store requests during offline mode and then dispatch them in order and delete the entries.