Abandon a session the rest of its install did not survive

src/app/session.ts

@@ -5,7 +5,7 @@ import type {Session} from "@welshman/app"
 import {getTestEvents, maybeGetTestSession} from "@lib/test/session"
 import {app, login, session} from "@app/core"
 import {wallet} from "@app/lightning"
-import {kv, ss, storage} from "@app/storage"
+import {hasCachedIdentity, kv, ss, storage} from "@app/storage"
 import {deactivateCurrentPomadeSession} from "@app/pomade"
 import {Push} from "@app/push"
 
@@ -58,11 +58,24 @@ const readLegacySession = async () => {
   return legacy ? toCurrentSession(legacy) : undefined
 }
 
+const readStoredSession = async () => {
+  const session = (await ss.get<Session>("session")) ?? (await readLegacySession())
+
+  // A nip01 secret is the account rather than a credential, and a local signer can't stall startup.
+  if (session && session.method !== "nip01" && !(await hasCachedIdentity())) {
+    await ss.set("session", undefined)
+
+    return undefined
+  }
+
+  return session
+}
+
 // The session derives from the app's user, so read it back at startup and persist it on a change.
 export const restoreSession = async () => {
   // Test-only: an injected window.__TEST_SESSION__ wins over storage and is stripped from production.
   const testSession = import.meta.env.DEV ? maybeGetTestSession() : undefined
-  const $session = testSession ?? (await ss.get<Session>("session")) ?? (await readLegacySession())
+  const $session = testSession ?? (await readStoredSession())
 
   if ($session) {
     await login($session)

src/app/storage.ts

@@ -206,6 +206,14 @@ const isExpired = (item: EventItem) =>
 
 type PlaintextItem = {key: string; value: string}
 
+const DATABASE_PREFIX = "flotilla-9gl"
+
+// indexeddb goes with the app container on every platform; the iOS keychain the session lives in does not.
+export const hasCachedIdentity = async () =>
+  typeof indexedDB.databases === "function"
+    ? (await indexedDB.databases()).some(db => db.name?.startsWith(DATABASE_PREFIX))
+    : true
+
 /** Caches an app's repository, tracker and local collections in indexeddb, one database per identity. */
 class Storage {
   ready: Promise<void>
@@ -220,10 +228,10 @@ class Storage {
 
   constructor(private readonly app: IApp) {
     // Every identity used to share one database; drop it rather than leave it on disk.
-    void deleteDB("flotilla-9gl")
+    void deleteDB(DATABASE_PREFIX)
 
     this.pubkey = User.require(app).pubkey
-    this.db = new IDB({name: `flotilla-9gl-${this.pubkey}`, stores: TABLES})
+    this.db = new IDB({name: `${DATABASE_PREFIX}-${this.pubkey}`, stores: TABLES})
     this.ready = this.start()
   }