Refactor relay list a bit

packages/app/src/plugins/relayLists.ts

@@ -55,7 +55,10 @@ export class RelayLists extends DerivedPlugin<RelayList> {
     return this.app.use(Thunks).publishToOutbox({event})
   }
 
-  addRelay = (url: string, mode: RelayMode) => this.update(builder => builder.addUrl(url, mode))
+  addRelay = (url: string, mode: RelayMode) =>
+    this.update(builder =>
+      mode === RelayMode.Read ? builder.addReadUrl(url) : builder.addWriteUrl(url),
+    )
 
   setReadRelays = (urls: string[]) => this.update(builder => builder.setReadUrls(urls))
 
@@ -64,7 +67,9 @@ export class RelayLists extends DerivedPlugin<RelayList> {
   removeRelay = async (url: string, mode: RelayMode) => {
     const user = User.require(this.app)
     const builder = new RelayListBuilder(await this.forceLoad(user.pubkey))
-    const event = await builder.removeUrl(url, mode).toTemplate(user.signer)
+    const event = await (
+      mode === RelayMode.Read ? builder.removeReadUrl(url) : builder.removeWriteUrl(url)
+    ).toTemplate(user.signer)
 
     // publishToOutbox is outbox-only, so build relays here to also notify the
     // removed relay of its removal

packages/domain/__tests__/RelayList.test.ts

@@ -60,10 +60,10 @@ describe("RelayList", () => {
 
   it("adds modeless and single-mode relays via a fresh builder", async () => {
     const tmpl = await new RelayListBuilder()
-      .addUrl(read, RelayMode.Read)
-      .addUrl(write, RelayMode.Write)
-      .addUrl(both, RelayMode.Read)
-      .addUrl(both, RelayMode.Write)
+      .addReadUrl(read)
+      .addWriteUrl(write)
+      .addReadUrl(both)
+      .addWriteUrl(both)
       .toTemplate(signer)
 
     expect(tmpl.kind).toBe(RELAYS)
@@ -75,9 +75,9 @@ describe("RelayList", () => {
 
   it("downgrades a modeless relay when one mode is removed", async () => {
     const tmpl = await new RelayListBuilder()
-      .addUrl(both, RelayMode.Read)
-      .addUrl(both, RelayMode.Write)
-      .removeUrl(both, RelayMode.Read)
+      .addReadUrl(both)
+      .addWriteUrl(both)
+      .removeReadUrl(both)
       .toTemplate(signer)
 
     expect(tmpl.tags).toContainEqual(["r", both, RelayMode.Write])

packages/domain/src/kinds/RelayList.ts

@@ -1,32 +1,30 @@
-import {uniq, uniqBy} from "@welshman/lib"
-import {RELAYS, RelayMode, getRelayTags, getRelayTagValues, normalizeRelayUrl} from "@welshman/util"
+import {nth, uniq, uniqBy, remove} from "@welshman/lib"
+import {RELAYS, getRelayTags, normalizeRelayUrl} from "@welshman/util"
 import {ListReader} from "../ListReader.js"
 import {ListBuilder} from "../ListBuilder.js"
 
+const getUrls = (tags: string[][], mode?: string) =>
+  uniqBy(
+    normalizeRelayUrl,
+    getRelayTags(tags)
+      .filter(t => !mode || !t[2] || t[2] === mode)
+      .map(nth(1)),
+  )
+
 // NIP-65 kind-10002 relay list.
 export class RelayList extends ListReader {
   readonly kind = RELAYS
 
   urls() {
-    return uniqBy(normalizeRelayUrl, getRelayTagValues(this.tags()))
+    return getUrls(this.tags())
   }
 
   readUrls() {
-    return uniqBy(
-      normalizeRelayUrl,
-      getRelayTags(this.tags())
-        .filter(t => !t[2] || t[2] === RelayMode.Read)
-        .map(t => t[1]),
-    )
+    return getUrls(this.tags(), "read")
   }
 
   writeUrls() {
-    return uniqBy(
-      normalizeRelayUrl,
-      getRelayTags(this.tags())
-        .filter(t => !t[2] || t[2] === RelayMode.Write)
-        .map(t => t[1]),
-    )
+    return getUrls(this.tags(), "write")
   }
 
   builder() {
@@ -37,73 +35,62 @@ export class RelayList extends ListReader {
 export class RelayListBuilder extends ListBuilder<RelayList> {
   readonly kind = RELAYS
 
-  readUrls() {
-    return uniqBy(
-      normalizeRelayUrl,
-      getRelayTags(this.publicTags)
-        .filter(t => !t[2] || t[2] === RelayMode.Read)
-        .map(t => t[1]),
-    )
+  addReadUrl(url: string) {
+    return this.addUrlForMode(url, "read")
   }
 
-  writeUrls() {
-    return uniqBy(
-      normalizeRelayUrl,
-      getRelayTags(this.publicTags)
-        .filter(t => !t[2] || t[2] === RelayMode.Write)
-        .map(t => t[1]),
-    )
+  addWriteUrl(url: string) {
+    return this.addUrlForMode(url, "write")
   }
 
-  addUrl(url: string, mode: RelayMode) {
+  removeReadUrl(url: string) {
+    return this.removeUrlForMode(url, "read")
+  }
+
+  removeWriteUrl(url: string) {
+    return this.removeUrlForMode(url, "write")
+  }
+
+  private findUrlTag(url: string) {
     const normalized = normalizeRelayUrl(url)
-    const existing = getRelayTags(this.publicTags).filter(
-      t => normalizeRelayUrl(t[1]) === normalized,
-    )
 
-    const priorModes = new Set<RelayMode | undefined>(
-      existing.map(t => t[2] as RelayMode | undefined),
-    )
+    return this.publicTags.find(t => t[0] === "r" && normalizeRelayUrl(t[1]) === normalized)
+  }
 
-    const alt = mode === RelayMode.Read ? RelayMode.Write : RelayMode.Read
-    const coversAlt = priorModes.has(undefined) || priorModes.has(alt)
+  private addUrlForMode(url: string, mode: "read" | "write") {
+    const existing = this.findUrlTag(url)
+    const alt = mode === "read" ? "write" : "read"
 
-    this.publicTags = this.publicTags.filter(
-      t => !(t[0] === "r" && normalizeRelayUrl(t[1]) === normalized),
-    )
-
-    this.publicTags.push(coversAlt ? ["r", url] : ["r", url, mode])
+    if (!existing) {
+      this.publicTags.push(["r", normalizeRelayUrl(url), mode])
+    } else if (existing[2] === alt) {
+      existing.splice(2)
+    }
 
     return this
   }
 
-  removeUrl(url: string, mode: RelayMode) {
-    const normalized = normalizeRelayUrl(url)
-    const existing = getRelayTags(this.publicTags).filter(
-      t => normalizeRelayUrl(t[1]) === normalized,
-    )
+  private removeUrlForMode(url: string, mode: "read" | "write") {
+    const existing = this.findUrlTag(url)
+    const alt = mode === "read" ? "write" : "read"
 
-    const alt = mode === RelayMode.Read ? RelayMode.Write : RelayMode.Read
-
-    const keepAlt = existing.some(t => !t[2] || t[2] === alt)
-
-    this.publicTags = this.publicTags.filter(
-      t => !(t[0] === "r" && normalizeRelayUrl(t[1]) === normalized),
-    )
-
-    if (keepAlt) {
-      this.publicTags.push(["r", url, alt])
+    if (existing) {
+      if (!existing[2]) {
+        existing[2] = alt
+      } else if (existing[2] === mode) {
+        this.publicTags = remove(existing, this.publicTags)
+      }
     }
 
     return this
   }
 
   setReadUrls(urls: string[]) {
-    return this.setUrlsForModes(urls, this.writeUrls())
+    return this.setUrlsForModes(urls, getUrls(this.publicTags, "write"))
   }
 
   setWriteUrls(urls: string[]) {
-    return this.setUrlsForModes(this.readUrls(), urls)
+    return this.setUrlsForModes(getUrls(this.publicTags, "read"), urls)
   }
 
   private setUrlsForModes(readUrls: string[], writeUrls: string[]) {
@@ -114,8 +101,8 @@ export class RelayListBuilder extends ListBuilder<RelayList> {
       read.has(url) && write.has(url)
         ? ["r", url]
         : read.has(url)
-          ? ["r", url, RelayMode.Read]
-          : ["r", url, RelayMode.Write],
+          ? ["r", url, "read"]
+          : ["r", url, "write"],
     )
 
     this.publicTags = [...otherTags, ...relayTags]