SharePoint 2013 doesn't allow publishing content directly into it's index. It does provide a way to create connectors that it can use to crawl non native content called SharePoint Business Data Connectivity (BDC).
In previous versions we offered a WCF based BDC connector to index content into SharePoint search. This component used a File System based intermediate repository, which brought a series of inconveniences regarding performance, security and scalability.
With the creation of STageR (the mongodb and node.js based staging repository) it was now possible to create a more compact solution that would leverage all the capabilities of STageR when indexing content into SharePoint Search.
Read more about our components:
Welcome to Publish to SharePoint 2013 for Aspire. Information for publishing, pushing documents acquired and processed by Aspire Publish to SharePoint 2013.
About the Publish to SharePoint 2013 publisher for Aspire, how it works, features,
Important requirements for the SharePoint 2013 Publisher operation.
Step by step tutorial to crawl your first Publish to SharePoint 2013
Questions and answers, including troubleshooting techniques
Questions and answers, components and troubleshooting techniques for developers
Publish to SharePoint 2013 concerning information