Some times our target systems expects messages to be received in sequencing order, In our previous releases of SOA by using mediator we can do sequencing. From 12c we have this option available in OSB as well.
“Re sequencing” is the option available in OSB 12C.
We have three types of re sequencing available in OSB.
Standard: This sequencer is used when incoming message contain numeric identifier. This numeric identifier is termed as Sequence Id.
FIFO: This sequencer works based on message arrival time. Whichever message received first, will be processed first.
Best Effort: It is used when we receive large number of messages in a short period of time and cannot provide information to the re-sequencer about the identifier to use for sequencing.
Lets start Configuring Re sequencing in OSB Pipeline.
Open the pipeline and go to Configuration tab.
In configuration page , go to Re sequencer tab and enable the option “Enable Re sequencer” and select the re sequence level as “Pipeline” and re sequence as “standard”.
If we have selected standard re sequencer then we need to provide values for sequence id and group.
Only sequence id is mandatory for you can skip group for this sequencer, empty group value means all the incoming messages will be in one group only.