Load results from repository when possible

packages/app/src/core.ts

@@ -1,5 +1,6 @@
-import {Repository, Relay} from "@welshman/util"
-import type {TrustedEvent} from "@welshman/util"
+import {isNil} from "@welshman/lib"
+import {Repository, Relay, LOCAL_RELAY_URL, getFilterResultCardinality} from "@welshman/util"
+import type {TrustedEvent, Filter} from "@welshman/util"
 import {Tracker, subscribe as baseSubscribe} from "@welshman/net"
 import type {SubscribeRequest} from "@welshman/net"
 import {createEventStore} from "@welshman/store"
@@ -21,17 +22,45 @@ export const relay = new Relay(repository)
 
 export const tracker = new Tracker()
 
-export const subscribe = (request: SubscribeRequest) => {
-  const sub = baseSubscribe({delay: 50, authTimeout: 3000, ...request})
+export const subscribe = (request: Partial<SubscribeRequest> & {filters: Filter[]}) => {
+  const events: TrustedEvent[] = []
+
+  // If we already have all results for any filter, don't send the filter to the network
+  for (const filter of request.filters.splice(0)) {
+    const cardinality = getFilterResultCardinality(filter)
+
+    if (!isNil(cardinality)) {
+      const results = repository.query([filter])
+
+      if (results.length === cardinality) {
+        for (const event of results) {
+          events.push(event)
+        }
+
+        break
+      }
+    }
+
+    request.filters.push(filter)
+  }
+
+  const sub = baseSubscribe({delay: 50, authTimeout: 3000, relays: [], ...request})
 
   sub.emitter.on("event", (url: string, e: TrustedEvent) => {
     repository.publish(e)
   })
 
+  // Keep cached results async so the caller can set up handlers
+  setTimeout(() => {
+    for (const event of events) {
+      sub.emitter.emit("event", LOCAL_RELAY_URL, event)
+    }
+  })
+
   return sub
 }
 
-export const load = (request: SubscribeRequest) =>
+export const load = (request: Partial<SubscribeRequest> & {filters: Filter[]}) =>
   new Promise<TrustedEvent[]>(resolve => {
     const sub = subscribe({closeOnEose: true, timeout: 3000, ...request})
     const events: TrustedEvent[] = []
@@ -40,7 +69,7 @@ export const load = (request: SubscribeRequest) =>
     sub.emitter.on("complete", () => resolve(events))
   })
 
-export const loadOne = (request: SubscribeRequest) =>
+export const loadOne = (request: Partial<SubscribeRequest> & {filters: Filter[]}) =>
   new Promise<TrustedEvent | null>(resolve => {
     const sub = subscribe({closeOnEose: true, timeout: 3000, ...request})