Creating templates programmatically: looking for directions

[mgopshtein]

I am trying to find some directions for the following problem (so far, from reading forums/tutorials still unsure where to start):

In out software we define a data flow graph, using different types of components (nodes). Each component is defined by a JSON file. For example, consider two components:
1. Mouse handler, which sends samples of type "mouse location"
2. Speed calculator, which receives samples of type "mouse location" and produces samples "mouse speed"

So each component will have a JSON with appropriate definitions. And a user need manually combine this components to a single Data Flow, where "mouse location" from 1st component goes to 2nd.

I would like to somehow programmatically read all such JSON definitions of the components, and create a template (I guess...) which can be imported to Visio and the user will build the Flow Graph in Visio instead of doing that manually.

Any references/ideas where to start are highly appreciated.
Michael