Hyperledger Fabric v1.0 and later does not provide a native REST API for interacting with peer and/or orderer nodes. If you have not done so, I'd advise taking a look at http://hyperledger-fabric.readthedocs.io/en/release-1.1/ to better understand the current Fabric architecture.
There is a project to provide a REST API server in front of Fabric nodes. It was not updated to support Fabric v1.1 (at least not yet) but does support Fabric v1.0 and should provide at least an example of how to add a REST API in front.
I'd also advice taking a look at the samples which are documented here as well. The fabcar sample provides a nice, simple example of how to connect a Node.js application to Fabric.