null array problem in json

I have written a function which scans all the files/directory in a given directory and returns a json object. I need to display this json object on the UI using jstree. I have written the function in go using recursion to scan all the files and directories rooted at that particular folder.

This is the type I am using to construct the whole structure

type Directory struct {
	Name string "data"
	SubDirs []Directory "children"
}

Now jstree accepts data structs of the following format.

json_data: {
        data: [
            "f1",
            "f2",
            {
                data: "f3",
                children: ["f4", "f5"]
            }
        ]
 }

and not of the format :-

json_data: {
        data: [
            {
              "data": "f1",
              "children": []
            } 
            {
              "data": "f2",
              "children": []
            } 
            {
                data: "f3",
                children: ["f4", "f5"]
            }
        ]
 }

(when I pass the above data structure format, it doesn't work probably since the "children" thing is null)

Thus the data structure Directory I have maintained doesn't suffice to construct the directory structure.

How do I solve this problem of constructing the Directory tree homogeneously?

The final one is not even valid JSON. The spec defines that empty arrays are valid and allowed. Try:

{
    "data": [
        {
            "data": "f1",
            "children": []
        },
        {
            "data": "f2",
            "children": []
        },
        {
            "data": "f3",
            "children": [
                "f4",
                "f5"
            ]
        }
    ]
}

Use JSONLint to validate your JSON objects.