fix: correct token expiration and JSON parsing bugs in XSUAA client

[o-liver]

Description

Fixes two critical bugs in the XSUAA OAuth2 client that prevent proper token refreshing and error handling.

Bugs Fixed

1. Token expiration logic (line 46): Removed secondsOfValidityLeft > 0 check that prevented expired tokens from being refreshed. When a token expires, secondsOfValidityLeft becomes negative, and the old condition secondsOfValidityLeft > 0 && secondsOfValidityLeft < oneHourInSeconds would never be true for expired tokens, causing them to never refresh.

2. JSON parsing error check (line 98): Changed if err != nil to if parsingErr != nil. The original code checked the wrong variable, silently ignoring JSON unmarshal failures and only catching earlier HTTP errors.

Impact

These bugs could cause:

• Bug 1: Authentication failures when tokens expire, requiring service restarts
• Bug 2: Silent failures when XSUAA returns malformed JSON, making debugging difficult

Changes

- if len(x.CachedAuthToken.AccessToken) == 0 ||
-     (secondsOfValidityLeft > 0 && secondsOfValidityLeft < oneHourInSeconds) {
+ if len(x.CachedAuthToken.AccessToken) == 0 ||
+     secondsOfValidityLeft < oneHourInSeconds {

- if err != nil {
+ if parsingErr != nil {

Testing

Unit tests pass. The fixes ensure:

• Expired tokens (negative secondsOfValidityLeft) trigger refresh
• JSON parsing errors are properly caught and returned

Related

These fixes were discovered during migration of the ANS/XSUAA packages to the tekton-logging-shim: https://github.tools.sap/cloudci/tekton-logging-shim/pull/81

[o-liver]

/go-it