How can I convert HTML code into a JSON object?

Issue

I am building an Angular 7 app. In this app I let the users edit HTML that I then want to convert into JSON to store it in a way that make sense.

In short, I want to take any HTML code and process it into a JSON object. How can I do this?

Solution

I'd parse the HTML into a DOM (you can do that client-side or server-side) and then serialize the aspects of the DOM that I cared about to an object, which I'd then use JSON.stringify on (if you really want JSON).

For instance:

function converter(dom) {
    if (dom.nodeType === Node.TEXT_NODE) {
        return dom.nodeValue;
    }
    if (dom.nodeType === Node.DOCUMENT_NODE) {
        dom = dom.documentElement;
    }
    const obj = {};
    obj.nodeType = dom.nodeType;
    if (dom.nodeType === Node.ELEMENT_NODE) {
        obj.tagName = dom.tagName;
        obj.attributes = []; // Array.from(obj.attributes) gives us a lot of things we don't want
        for (let i = 0, len = dom.attributes.length; i < len; ++i) {
            const attr = dom.attributes[i];
            obj.attributes.push({name: attr.name, value: attr.value});
        }
        obj.children = [];
        for (let child = dom.firstChild; child; child = child.nextSibling) {
            obj.children.push(converter(child));
        }
    } else {
        obj.nodeValue = dom.nodeValue;
    }
    return obj;
}
const json = JSON.stringify(converter(document.getElementById("example")), null, 4);
console.log(json);

.as-console-wrapper {
    max-height: 100% !important;
}

<div id="example" class="ex">
  <span>Span 1</span>
  <span>Span 2</span>
  <!-- comment -->
  <span>
    Span 3
    <span>Inner span</span>
  </span>
</div>

Obviously that's just a rough sketch, not a completely baked solution.

Answered By - T.J. Crowder