Re-work feed requests

packages/feeds/src/request.ts

@@ -0,0 +1,110 @@
+import {partition, now, nthEq, race} from "@welshman/lib"
+import {makeEvent, Filter, getPubkeyTagValues, TrustedEvent} from "@welshman/util"
+import {Nip01Signer, ISigner} from "@welshman/signer"
+import {Repository} from "@welshman/relay"
+import {Router, getFilterSelections, addMinimalFallbacks} from "@welshman/router"
+import {Tracker, request} from "@welshman/net"
+import {makeDvmRequest} from "@welshman/dvm"
+
+export type RequestPageOptions = {
+  filters?: Filter[]
+  relays?: string[]
+  signal?: AbortSignal
+  tracker?: Tracker
+  repository?: Repository
+  onEvent?: (event: TrustedEvent) => void
+}
+
+export const requestPage = async ({
+  filters = [{}],
+  relays = [],
+  onEvent,
+  signal,
+  repository,
+  tracker = new Tracker(),
+}: RequestPageOptions) => {
+  if (relays.length > 0) {
+    return request({tracker, signal, relays, filters, onEvent, autoClose: true})
+  }
+
+  const promises: Promise<TrustedEvent[]>[] = []
+  const [withSearch, withoutSearch] = partition(f => Boolean(f.search), filters)
+
+  if (withSearch.length > 0) {
+    promises.push(
+      request({
+        signal,
+        tracker,
+        onEvent,
+        threshold: 0.1,
+        autoClose: true,
+        filters: withSearch,
+        relays: Router.get().Search().getUrls(),
+      }),
+    )
+  }
+
+  if (withoutSearch.length > 0) {
+    promises.push(
+      ...getFilterSelections(filters).flatMap(({relays, filters}) =>
+        request({tracker, signal, onEvent, relays, filters, threshold: 0.8, autoClose: true}),
+      ),
+    )
+  }
+
+  // Break out selections by relay so we can complete early after a certain number
+  // of requests complete for faster load times
+  await race(withSearch.length > 0 ? 0.1 : 0.8, promises)
+
+  // Wait until after we've queried the network to access our local cache. This results in less
+  // snappy response times, but is necessary to prevent stale stuff that the user has already seen
+  // from showing up at the top of the feed
+  if (repository) {
+    for (const event of repository.query(filters)) {
+      onEvent?.(event)
+    }
+  }
+}
+
+export type RequestDVMOptions = {
+  kind: number
+  tags?: string[][]
+  relays?: string[]
+  signer?: ISigner
+  onResult: (event: TrustedEvent) => void
+}
+
+export const requestDVM = async ({
+  kind,
+  onResult,
+  tags = [],
+  relays = [],
+  signer = Nip01Signer.ephemeral(),
+}: RequestDVMOptions) => {
+  if (relays.length === 0) {
+    relays = Router.get()
+      .FromPubkeys(getPubkeyTagValues(tags))
+      .policy(addMinimalFallbacks)
+      .getUrls()
+  }
+
+  if (!tags.some(nthEq(0, "expiration"))) {
+    tags.push(["expiration", String(now() + 60)])
+  }
+
+  if (!tags.some(nthEq(0, "relays"))) {
+    tags.push(["relays", ...relays])
+  }
+
+  if (!tags.some(nthEq(1, "user"))) {
+    tags.push(["param", "user", await signer.getPubkey()])
+  }
+
+  if (!tags.some(nthEq(1, "max_results"))) {
+    tags.push(["param", "max_results", "200"])
+  }
+
+  const event = await signer.sign(makeEvent(kind, {tags}))
+
+  await makeDvmRequest({relays, event, onResult})
+}