Node-RED exposes an extensive API at runtime. While most of this is not available within your flows, much of it is available to custom nodes. Unfortunately, documentation for the API lags behind development. This page documents some of the key things I’ve learned about the API, what it does and how it works.
The official API documentation is here in the Node-RED docs.
The API is accessed via the
Available in Function Nodes
Available in Custom Nodes
See: https://groups.google.com/forum/#!searchin/node-red/RED.util/node-red/dOrpj2S_hi0/X0LthFt0BAAJ “For a variety of reasons, you cannot use the JSON.stringfy/parse trick on messages that originate from the HTTP In node.”