X OAuth2 refresh tokens are single-use: each refresh rotates the pair and
invalidates the previous refresh_token, and reusing a rotated one kills the
whole family. Three things made this fragile and disconnected accounts far
more often than necessary:
- The proactive refresh job called refreshToken() directly, bypassing the
access-token-first guard in verify() and rotating on every run.
- RefreshExpiringTokens used a 2h window on an hourly schedule — equal to the
2h access-token lifetime — so every X account was rotated every hour even
while its token was still valid.
- A single 4xx refresh failure disconnected the account without checking
whether a concurrent refresh had already persisted a working token.
Changes:
- RefreshSocialToken now routes through verify() (access-token-first), so it
only rotates when the access_token is actually invalid.
- Shrink the proactive window to 30m and run the command every 15m, so the
window still covers the run interval but rotation happens near real expiry.
- verify() tolerates the lost-rotation race: on a 4xx refresh, reload and
verify with a concurrently-refreshed token before marking TokenExpired.
Refs #126
2f4b974130