[GOBBLIN-611] Ensure node events are processed before edge events in GitFlowGraphMonitor

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.14.0
• Fix Version/s: 0.14.0
• Component/s: gobblin-service
• Assignee: Sudarshan Vasudevan
• Reporter: Sudarshan Vasudevan
• Created: 11/Oct/18 23:42
• Updated: 12/Oct/18 17:20
• Resolved: 12/Oct/18 17:20

Description

Currently, if there are multiple changes to GitFlowGraph in a commit, the FlowGraph may end up in an inconsistent state. E.g. consider a commit where node1, node2 and edge from node1 to node2 are added. If the changes are processed in the following order:  add node1, (ii) add edge from node1->node2, and (iii) add node2, then the edge addition is skipped since node2 does not yet exist in the graph. This task ensures that all node related changes are processed and applied to the FlowGraph before edge related changes are applied.