If you are using some way to read data from a local file. Then just read it using this method.
1) I would expect you to be using some build system like webpack or browserify or something of that sort. You can probably tweak that a bit to accept reading of json files as well and just get that file using the ES5 stlye require or ES6 way using import .
2) Else, if you want to read it over streams or something like that try using the fs from node.
Cheers Hope this helps :)