add codes

src/libs/auth.js

@@ -0,0 +1,37 @@
+import storage from "./storage";
+import { STOKEY_MSAUTH, URL_MICROSOFT_AUTH } from "../config";
+import { fetchData } from "./fetch";
+
+const parseMSToken = (token) => JSON.parse(atob(token.split(".")[1])).exp;
+
+/**
+ * 闭包缓存token，减少对storage查询
+ * @returns
+ */
+const _msAuth = () => {
+  let { token, exp } = {};
+
+  return async () => {
+    // 查询内存缓存
+    const now = Date.now();
+    if (token && exp * 1000 > now + 1000) {
+      return [token, exp];
+    }
+
+    // 查询storage缓存
+    const res = (await storage.getObj(STOKEY_MSAUTH)) || {};
+    token = res.token;
+    exp = res.exp;
+    if (token && exp * 1000 > now + 1000) {
+      return [token, exp];
+    }
+
+    // 缓存没有或失效，查询接口
+    token = await fetchData(URL_MICROSOFT_AUTH);
+    exp = parseMSToken(token);
+    await storage.setObj(STOKEY_MSAUTH, { token, exp });
+    return [token, exp];
+  };
+};
+
+export const msAuth = _msAuth();