feat(desktop): allow leaving your final community

desktop/src-tauri/src/commands/relay_members.rs

@@ -17,8 +17,15 @@ struct RelayInformationDocument {
 }
 
 #[tauri::command]
-pub async fn relay_requires_membership(state: State<'_, AppState>) -> Result<bool, String> {
-    let url = format!("{}/info", relay_api_base_url_with_override(&state));
+pub async fn relay_requires_membership(
+    relay_url: Option<String>,
+    state: State<'_, AppState>,
+) -> Result<bool, String> {
+    let base_url = relay_url
+        .as_deref()
+        .map(crate::relay::relay_http_base_url)
+        .unwrap_or_else(|| relay_api_base_url_with_override(&state));
+    let url = format!("{}/info", base_url.trim_end_matches('/'));
     let response = state
         .http_client
         .get(url)

desktop/src/app/App.tsx

@@ -41,6 +41,7 @@ import { PendingInviteGate } from "@/features/onboarding/ui/PendingInviteGate";
 import { KeyringLockedScreen } from "@/features/onboarding/ui/KeyringLockedScreen";
 import { RelaunchRequiredScreen } from "@/features/onboarding/ui/RelaunchRequiredScreen";
 import { ResetFailedScreen } from "@/features/onboarding/ui/ResetFailedScreen";
+import { loadCommunityDiscoveryAfterLeave } from "@/features/communities/communityStorage";
 import { useCommunityInit } from "@/features/communities/useCommunityInit";
 import { useNestNotifications } from "@/features/communities/useNestNotifications";
 import { useCommunities } from "@/features/communities/useCommunities";
@@ -319,6 +320,8 @@ function CommunityApp({
   const [isCommunityChangeOpen, setIsCommunityChangeOpen] = useState(false);
   const [resumeFirstCommunityPage, setResumeFirstCommunityPage] =
     useState<FirstCommunityPage | null>(null);
+  const isFindingCommunityAfterLeave =
+    activeCommunity === null && loadCommunityDiscoveryAfterLeave();
 
   // Surface nest-related backend events (repos-dir errors, legacy migration)
   // as toasts. Mounted before useCommunityInit so the listeners are registered
@@ -343,6 +346,7 @@ function CommunityApp({
     activeCommunity,
     communityKey,
     sharedIdentity,
+    isFindingCommunityAfterLeave,
   );
 
   const transitionCommunity = useCallback(
@@ -512,7 +516,9 @@ function CommunityApp({
       appContent = (
         <WelcomeSetup
           initialPage={resumeFirstCommunityPage ?? undefined}
-          onBack={onBackToMachineConfig}
+          onBack={
+            isFindingCommunityAfterLeave ? undefined : onBackToMachineConfig
+          }
         />
       );
     } else if ("error" in community && community.error) {

desktop/src/app/AppShell.tsx

@@ -779,7 +779,6 @@ export function AppShell() {
               <CommunityRail
                 activeCommunityId={communitiesHook.activeCommunity?.id ?? null}
                 onAddCommunity={addCommunityDialog.openDialog}
-                onRemoveCommunity={(id) => void handleRemoveCommunity(id)}
                 onReorderCommunities={communitiesHook.reorderCommunities}
                 onSwitchCommunity={handleSwitchCommunity}
                 onUpdateCommunity={communitiesHook.updateCommunity}
@@ -872,9 +871,7 @@ export function AppShell() {
                         onOpenAddCommunity={addCommunityDialog.openDialog}
                         onSendFeedback={() => setIsSendFeedbackOpen(true)}
                         onUpdateCommunity={communitiesHook.updateCommunity}
-                        onRemoveCommunity={(id) =>
-                          void handleRemoveCommunity(id)
-                        }
+                        onRemoveCommunity={handleRemoveCommunity}
                         onSwitchCommunity={handleSwitchCommunity}
                         onCreateAgent={() => requestOpenCreateAgent()}
                         selfPresenceStatus={presenceSession.currentStatus}

desktop/src/app/useCommunityNavigationTransitions.ts

@@ -12,7 +12,9 @@ import {
   markPendingCommunityRestore,
   saveCommunityDestination,
 } from "@/features/communities/communityNavigationStorage";
+import { markCommunityDiscoveryAfterLeave } from "@/features/communities/communityStorage";
 import type { useCommunities } from "@/features/communities/useCommunities";
+import { leaveCommunity } from "@/features/communities/leaveCommunity";
 
 type Communities = ReturnType<typeof useCommunities>;
 type ShellRoute = ReturnType<typeof deriveShellRoute>;
@@ -71,14 +73,38 @@ export function useCommunityNavigationTransitions({
 
   const removeCommunity = React.useCallback(
     async (id: string) => {
-      if (id !== communities.activeCommunity?.id) {
-        communities.removeCommunity(id);
-        return;
-      }
+      const target = communities.communities.find(
+        (community) => community.id === id,
+      );
+      if (!target) return;
+
       const fallback = communities.communities.find(
         (community) => community.id !== id,
       );
-      if (!fallback) return;
+
+      // Do not touch local state until this relay has explicitly accepted the
+      // signed NIP-43 leave request. Rejections and timeouts bubble back to the
+      // dialog so the person can retry without losing their community config.
+      const leaveResult = await leaveCommunity(
+        target.relayUrl,
+        communities.activeCommunity?.relayUrl,
+      );
+
+      if (id !== communities.activeCommunity?.id) {
+        communities.removeCommunity(id);
+        return leaveResult;
+      }
+
+      if (!fallback) {
+        if (!markCommunityDiscoveryAfterLeave()) {
+          throw new Error(
+            "Membership was removed, but community discovery state could not be saved. Restart Buzz and try again.",
+          );
+        }
+        await goHome({ replace: true });
+        communities.removeCommunity(id);
+        return leaveResult;
+      }
 
       await runCommunityViewTransition(async () => {
         saveActiveDestination();
@@ -93,6 +119,7 @@ export function useCommunityNavigationTransitions({
         }
         communities.removeCommunity(id);
       });
+      return leaveResult;
     },
     [communities, goHome, router.history, saveActiveDestination],
   );

desktop/src/features/communities/communityStorage.test.mjs

@@ -4,7 +4,11 @@ import test from "node:test";
 import {
   clearCommunityStorage,
   initFirstCommunity,
+  loadCommunities,
+  loadCommunityDiscoveryAfterLeave,
+  markCommunityDiscoveryAfterLeave,
   migrateLegacyCommunityStorage,
+  saveCommunities,
   shouldAutoConnectDefaultRelay,
 } from "./communityStorage.ts";
 
@@ -89,16 +93,42 @@ test("failed first-community write preserves existing community data", () => {
   assert.equal(storage.getItem("buzz-active-workspace-id"), "legacy");
 });
 
-test("clearCommunityStorage removes new and legacy state", () => {
+test("loading an existing community clears stale final-leave discovery", () => {
+  const storage = createMemoryStorage({
+    "buzz-communities": '[{"id":"joined"}]',
+    "buzz-community-discovery-after-leave": "1",
+  });
+  globalThis.localStorage = storage;
+  globalThis.window = { localStorage: storage };
+
+  assert.deepEqual(loadCommunities(), [{ id: "joined" }]);
+  assert.equal(loadCommunityDiscoveryAfterLeave(storage), false);
+});
+
+test("completed final leave persists discovery until a community is saved", () => {
+  const storage = createMemoryStorage();
+  globalThis.localStorage = storage;
+  globalThis.window = { localStorage: storage };
+
+  assert.equal(markCommunityDiscoveryAfterLeave(storage), true);
+  assert.equal(loadCommunityDiscoveryAfterLeave(storage), true);
+
+  assert.equal(saveCommunities([{ id: "joined" }]), true);
+  assert.equal(loadCommunityDiscoveryAfterLeave(storage), false);
+});
+
+test("clearCommunityStorage preserves completed final-leave discovery", () => {
   const storage = createMemoryStorage({
     "buzz-communities": "new",
     "buzz-active-community-id": "new",
     "buzz-workspaces": "old",
     "buzz-active-workspace-id": "old",
+    "buzz-community-discovery-after-leave": "1",
   });
 
   clearCommunityStorage(storage);
   migrateLegacyCommunityStorage(storage);
 
-  assert.equal(storage.length, 0);
+  assert.equal(storage.length, 1);
+  assert.equal(loadCommunityDiscoveryAfterLeave(storage), true);
 });

desktop/src/features/communities/communityStorage.ts

@@ -6,6 +6,8 @@ const COMMUNITIES_KEY = "buzz-communities";
 const ACTIVE_COMMUNITY_KEY = "buzz-active-community-id";
 const LEGACY_WORKSPACES_KEY = "buzz-workspaces";
 const LEGACY_ACTIVE_WORKSPACE_KEY = "buzz-active-workspace-id";
+const COMMUNITY_DISCOVERY_AFTER_LEAVE_KEY =
+  "buzz-community-discovery-after-leave";
 
 /**
  * Expand a leading `~` to the user's home directory. The backend rejects
@@ -57,6 +59,9 @@ export function loadCommunities(): Community[] {
     if (!Array.isArray(parsed)) {
       return [];
     }
+    if (parsed.length > 0) {
+      localStorage.removeItem(COMMUNITY_DISCOVERY_AFTER_LEAVE_KEY);
+    }
     // Migration: older builds stored the user's `nsec` in localStorage and
     // re-applied it to the backend on every reload, which silently overwrote
     // any `import_identity` result with the original generated key. The
@@ -82,10 +87,37 @@ export function loadCommunities(): Community[] {
 }
 
 export function saveCommunities(communities: Community[]): boolean {
-  return setLocalStorageItemWithRecovery(
+  const didSave = setLocalStorageItemWithRecovery(
     COMMUNITIES_KEY,
     JSON.stringify(communities),
   );
+  if (didSave && communities.length > 0) {
+    localStorage.removeItem(COMMUNITY_DISCOVERY_AFTER_LEAVE_KEY);
+  }
+  return didSave;
+}
+
+export function loadCommunityDiscoveryAfterLeave(
+  storage: Storage = localStorage,
+): boolean {
+  return storage.getItem(COMMUNITY_DISCOVERY_AFTER_LEAVE_KEY) === "1";
+}
+
+export function markCommunityDiscoveryAfterLeave(
+  storage: Storage = localStorage,
+): boolean {
+  if (typeof window !== "undefined" && storage === window.localStorage) {
+    return setLocalStorageItemWithRecovery(
+      COMMUNITY_DISCOVERY_AFTER_LEAVE_KEY,
+      "1",
+    );
+  }
+  try {
+    storage.setItem(COMMUNITY_DISCOVERY_AFTER_LEAVE_KEY, "1");
+    return true;
+  } catch {
+    return false;
+  }
 }
 
 export function clearCommunityStorage(storage: Storage = localStorage): void {