applesauce

Appearance

QueryStore ​

The QueryStore class wraps the EventStore and allows you to run complex Queries against it

The role of the query store is to keep track of all queries, wrap them in the rxjs share operator and ensure only one instance of each is created

IMPORTANT

For performance reasons UI components should only subscribe to the QueryStore and NOT the EventStore

Running a query ​

The queryStore.createQuery can be used to create and register a query in the query store

Queries are not started until the they are subscribe to. and they are destroyed when all subscriptions are closed

ts
// The first argument is the query constructor and the remaining are passed to the query
const observable = queryStore.createQuery(TimelineQuery, [{ kinds: [1] }]);

// start the query by subscribing to it
observable.subscribe((events) => {
  console.log(events);
});

Performance ​

The query store keeps track of what queries have been created and will ensure that only a single instance is created

ts
const notes = queryStore.createQuery(TimelineQuery, [{ kinds: [1] }]);

// lots of code...

const otherTimeline = queryStore.createQuery(TimelineQuery, [{ kinds: [1] }]);

// because the query with the same arguments was created before
// the second call will return the same observable
console.log(otherTimeline === notes);

// this will create a new query because the filter is different
const files = queryStore.createQuery(TimelineQuery, [{ kinds: [1063] }]);

Prebuilt queries ​

The QueryStore instance has a few helper methods in order to easily create common queries

Single event ​

The queryStore.event method creates a SingleEventQuery query

Replaceable event ​

The queryStore.replaceable method creates a ReplaceableQuery query

Profile ​

The queryStore.profile method creates a ProfileQuery query

Timeline ​

The queryStore.timeline method creates a TimelineQuery query

Reactions ​

The queryStore.reactions method creates a ReactionsQuery query