[SYNCOPE-855] Synchronization token management enhancement in case of errors

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.2.7, 2.0.0-M2
• Fix Version/s: 1.2.8, 2.0.0-M3
• Component/s: core
• Assignee: Francesco Chicchiriccò
• Reporter: Francesco Chicchiriccò
• Created: 13/May/16 14:11
• Updated: 08/Sep/16 07:50
• Resolved: 24/May/16 14:36

Description

The overall logic of the synchronization (1.2) / incremental pull (2.0) process can be summarized as:

1. invoke underlying connector's getLatestSyncToken
2. invoke underlying connector's sync
3. store the value for getLatestSyncToken for subsequent invocation

As a consequence, when one synchronizing item (SyncDelta) generates an error, the whole process might be interrupted without saving the updated sync token, and next invocation will start again from the beginning, without considering the successful items passed before the error occurred.

The process should be changed as follows, instead:

1. invoke underlying connector's getLatestSyncToken
2. invoke underlying connector's sync: for each SyncDelta, temporary store the related syncToken field;
3. store the last successful item's syncToken value - or getLatestSyncToken if no error occurred - for subsequent invocation

Issue Links

• breaks: SYNCOPE-923 Sync / Pull task not configured for delete causes incremental sync to prematurely stop
• breaks: SYNCOPE-936 Sync token reset to NULL when no SyncDelta items are available