Although SharePoint 2013 doesn't allow publishing content directly into its index, it does provide a way to create connectors that it can use to crawl non-native content based on the SharePoint Business Data Connectivity (BDC) model. In previous versions, we offered a Windows Communication Foundation (WCF)-based BDC connector to index content into SharePoint Search. This component used a file system-based intermediate repository, which wrought a series of inconveniences regarding performance, security and scalability. With the creation of StageR (a mongodb and node.js-based staging repository), it's now possible to create a more compact solution when indexing content into SharePoint Search that also leverages all of the capabilities of StageR .
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