init with react+axum+spacetimedb

src/persistence/storage.ts

@@ -0,0 +1,65 @@
+export type JsonStorage = Pick<Storage, 'getItem' | 'setItem' | 'removeItem'>;
+
+export function isRecord(value: unknown): value is Record<string, unknown> {
+  return Boolean(value) && typeof value === 'object' && !Array.isArray(value);
+}
+
+export function getJsonStorage(storage?: JsonStorage | null) {
+  if (storage !== undefined) {
+    return storage;
+  }
+
+  if (typeof window === 'undefined') {
+    return null;
+  }
+
+  return window.localStorage;
+}
+
+export function readStoredJson<T>({
+  key,
+  parse,
+  storage,
+}: {
+  key: string;
+  parse: (value: unknown) => T | null;
+  storage?: JsonStorage | null;
+}) {
+  const resolvedStorage = getJsonStorage(storage);
+  if (!resolvedStorage) {
+    return null;
+  }
+
+  const raw = resolvedStorage.getItem(key);
+  if (!raw) {
+    return null;
+  }
+
+  try {
+    return parse(JSON.parse(raw));
+  } catch {
+    return null;
+  }
+}
+
+export function writeStoredJson({
+  key,
+  value,
+  storage,
+}: {
+  key: string;
+  value: unknown;
+  storage?: JsonStorage | null;
+}) {
+  const resolvedStorage = getJsonStorage(storage);
+  if (!resolvedStorage) {
+    return false;
+  }
+
+  resolvedStorage.setItem(key, JSON.stringify(value));
+  return true;
+}
+
+export function removeStoredJson(key: string, storage?: JsonStorage | null) {
+  getJsonStorage(storage)?.removeItem(key);
+}