Uber Mobile SDK访问令牌续期机制及手动续期方法问询

Great question—let’s walk through how the Uber Mobile SDK handles token refresh by default, then break down how you can implement manual renewal for your specific SSO-to-server workflow.

Default SDK Token Refresh Behavior #

First, it’s important to note that the Uber Mobile SDK automatically handles access token renewal in the background when it detects an expiring token. It uses the refresh token (returned during the initial OAuth flow) to fetch a new access token from Uber’s auth endpoint, and this process is entirely transparent to developers. That’s why you won’t find an explicit "manual renew" method exposed in the SDK’s public API.

Implementing Manual Token Renewal for Your Use Case #

Since your workflow involves passing the access token to your server but keeping token management on the mobile side, here’s a secure approach to manual renewal:

1. Persist the Refresh Token Securely #

During the initial SSO/OAuth flow, make sure you capture and securely store both the access token and refresh token on the device:

• For iOS: Use the Keychain to store tokens (never plaintext or UserDefaults).
• For Android: Use the Keystore system for encrypted storage.
  The refresh token is critical here—it’s what you’ll use to request a new access token when needed.

2. Trigger Manual Renewal via Uber’s OAuth Token Endpoint #

While the SDK doesn’t expose a manual renew method, you can directly call Uber’s OAuth 2.0 token endpoint to refresh tokens. Important: Never hardcode your Uber client_secret in mobile app code (it’s insecure and can be reverse-engineered). Instead, use your backend as an intermediary:

• On the mobile app, when you want to trigger renewal (e.g., on app launch, or when the access token is nearing expiration), send the stored refresh token to your backend server.
• Your backend then sends a POST request to https://login.uber.com/oauth/v2/token with these parameters:

  grant_type=refresh_token
  client_id=YOUR_UBER_CLIENT_ID
  client_secret=YOUR_UBER_CLIENT_SECRET
  refresh_token=USER_REFRESH_TOKEN
  

• Uber’s endpoint will return a new access token, a new refresh token (always use this new one for future renewals), and an expires_in value (time in seconds until the new access token expires).

3. Sync Updated Tokens Across Mobile and Server #

• Your backend sends the new access token and refresh token back to the mobile app.
• The mobile app updates its secure storage with the new tokens.
• The mobile app also syncs the new access token to your server, ensuring future Uber requests from your server use the valid token.

4. Handle Edge Cases #

• Refresh Token Expiration: Refresh tokens themselves have a limited lifespan. If Uber returns an error indicating the refresh token is invalid/expired, you’ll need to redirect the user back through the SSO flow to get a new set of tokens.
• Token Expiry Checking: Calculate the access token’s expiration time using the expires_in value returned during initial auth or renewal. Trigger manual renewal a few minutes before expiration to avoid downtime.

Final Notes #

Avoid relying on any internal, non-public SDK methods for manual renewal—these can change without warning and break your implementation. Sticking to the official OAuth endpoint via your backend is the most secure and maintainable approach.

内容的提问来源于stack exchange，提问作者Pilon