Initial commit

src/token/TokenStore.ts

@@ -0,0 +1,101 @@
+/**
+ * Token persistence interface and localStorage-backed default implementation.
+ *
+ * The TokenStore is injected via RudderClientOptions. When none is provided
+ * the client uses {@link createDefaultTokenStore}: localStorage in browsers,
+ * with a silent in-memory fallback where localStorage is unavailable
+ * (SSR, private mode). Consumers can provide a custom implementation for
+ * alternative storage backends (e.g., sessionStorage, secure cookies).
+ */
+export interface TokenStore {
+  /** Returns the current access token, or null if not authenticated. */
+  getAccessToken(): string | null;
+
+  /** Returns the current refresh token, or null if not available. */
+  getRefreshToken(): string | null;
+
+  /** Persists access and refresh tokens after a successful login. */
+  saveTokens(accessToken: string, refreshToken: string): void;
+
+  /** Removes all stored tokens (logout). */
+  clear(): void;
+}
+
+const STORAGE_KEY_ACCESS = 'rudder_access_token';
+const STORAGE_KEY_REFRESH = 'rudder_refresh_token';
+
+/**
+ * Creates the default TokenStore: localStorage-backed when usable, otherwise
+ * a silent in-memory fallback (tokens live for the page session only).
+ */
+export function createDefaultTokenStore(): TokenStore {
+  try {
+    const probe = 'rudder_storage_probe';
+    localStorage.setItem(probe, '1');
+    localStorage.removeItem(probe);
+    return createLocalStorageTokenStore();
+  } catch {
+    return createMemoryTokenStore();
+  }
+}
+
+/**
+ * Creates a TokenStore backed by the browser's localStorage.
+ *
+ * Uses keys `rudder_access_token` and `rudder_refresh_token`.
+ */
+export function createLocalStorageTokenStore(): TokenStore {
+  return {
+    getAccessToken(): string | null {
+      try {
+        return localStorage.getItem(STORAGE_KEY_ACCESS);
+      } catch {
+        return null;
+      }
+    },
+
+    getRefreshToken(): string | null {
+      try {
+        return localStorage.getItem(STORAGE_KEY_REFRESH);
+      } catch {
+        return null;
+      }
+    },
+
+    saveTokens(accessToken: string, refreshToken: string): void {
+      try {
+        localStorage.setItem(STORAGE_KEY_ACCESS, accessToken);
+        localStorage.setItem(STORAGE_KEY_REFRESH, refreshToken);
+      } catch {
+        // Storage full or unavailable — silently ignore.
+      }
+    },
+
+    clear(): void {
+      try {
+        localStorage.removeItem(STORAGE_KEY_ACCESS);
+        localStorage.removeItem(STORAGE_KEY_REFRESH);
+      } catch {
+        // Storage unavailable — silently ignore.
+      }
+    },
+  };
+}
+
+function createMemoryTokenStore(): TokenStore {
+  let accessToken: string | null = null;
+  let refreshToken: string | null = null;
+
+  return {
+    getAccessToken: () => accessToken,
+    getRefreshToken: () => refreshToken,
+    saveTokens(access, refresh) {
+      accessToken = access;
+      refreshToken = refresh;
+    },
+    clear() {
+      accessToken = null;
+      refreshToken = null;
+    },
+  };
+}