Iterate through an Object without knowing its depth

Question

I'm trying to iterate thru an object but without knowing its depth. My task is to go thru all objects and get the 'content'. if 'has_content' is false, then content does not have anything but its child/children might have content. I'm supposed to go to the last child. I am thinking of solving it by recursion. I'm pretty new to js. help is appreciated.

the result of the object below should be ["hello", "world", "last one", "level 1"].

'use strict'
let obj1 = {
    "has_content": false,
    "content": null,
    "nodes": [
        {
            "has_content": false,
            "content": null,
            "nodes": [
                {
                    "has_content": true,
                    "content": "Hello",
                    "nodes": [
                        {
                            "has_content": true,
                            "content": "world",
                            "nodes": [
                                {
                                    "has_content": true,
                                    "content": "last one"
                                }
                            ]
                        }
                    ]
                }
            ]
        }
    ], 
    "has_content": false,
    "content": null,
    "nodes": [
        {
            "has_content": true,
            "content": "level 1"
        }
    ]
}