Reverse Synchronization 

For integration that requires synchronization in both sides, there is a possibility to declare export process on connector level. Your connector should implement Oro\Bundle\IntegrationBundle\Provider\TwoWaySyncConnectorInterface to expose the job name that will make export.

Export Job Definition 

The definition of the export job is similar to import. It is an additional job for Oro\Bundle\BatchBundle that should be added to batch_job.yml. A job might be declared with multiple steps, but a good practice is to use one connector for one entity. In order to read a entity from the database, there is additional reader placed in OroIntegrationBundle oro_integration.reader.entity.by_id, it takes the EntityReaderById::ID_FILTER option from the context object(ContextInterface) for the matching entity to read.

Note

For now only non-composite identifiers are supported.

Example:

batch_job.yml 
example_export:
    title: Job title here
    type:  export
    steps:
        export_entity_1:
            title:      Step title here
            class:      Oro\Bundle\BatchBundle\Step\ItemStep
            services:
                reader:    oro_integration.reader.entity.by_id  # read entity from database by identifier
                processor: YOUR_PROCESSOR                       # service which process each record. Could prepare changeset for writer.
                writer:    YOUR_REVERSE_WRITER                  # service that are responsible for pushing data to remote instance
            parameters: ~
        # .... another steps

Processor and writer could be initialized in your bundle in service.yaml.

Example:

YOUR_PROCESSOR:
    class: Acme\Bundle\DemoBundle\Processor\YourProcessor
YOUR_REVERSE_WRITER:
    class:Acme\Bundle\DemoBundle\Writer\YourReverseWriter

Where YOUR_PROCESSOR.class - should implement Oro\Bundle\ImportExportBundle\Processor\ProcessorInterface and YOUR_REVERSE_WRITER.class - should implement Oro\Bundle\ImportExportBundle\Processor\WriterInterface

Implementation of those classes is platform-specific, so there is no abstraction layer.