This was usful in demonstration for extracting json data from html. Data as JSON from html document values with element's names as the keys. TODO: Handle name collisions

yieldData.js

let print = function(s){
        console.log(s);
      }
      
      let hasValue = function(x){
        return x!==null && x!==undefined ;
      }
      
      let attemptListToObject = function(a){
        if(a.every(x => x instanceof Object && Object.keys(x).length == 1)){
          let ans = {};
          for (const x of a){
            if(Object.keys(ans).includes(Object.keys(x)[0])){
              return a;
            }
            ans[Object.keys(x)[0]] = x[Object.keys(x)[0]];
          }
          return ans;
        }
        return a;
      }
      
      let yieldData = function(element){
        let name = element.getAttribute("name");
        let tagName = element.tagName;
        let ret = {};
        let filterFunction = function(x){
          if(x!==null && x!==undefined){
            if (x instanceof Array){
              if (x.length == 0) {
                return false;
              }return true;
            }
            if (x instanceof Object){
              if (Object.keys(x).length == 0) {
                return false;
              }
              return true;
            }
            return true
          }
          return false;
        }
        if (element.hasChildNodes() && (tagName != "SELECT")){
          ret = Array.from(element.children).map(child => yieldData(child)).filter(filterFunction);
        }
        else if (tagName == "LABEL" || tagName == "TH" || tagName == "BR" || tagName == "P"){
          return;
        }
        else if(name === null){
          return
        }
        else if (tagName == "INPUT"){
          ret = element.checked;
        }
        else if (tagName == "TEXTAREA"){
          ret = element.value;
        }
        else if (tagName == "SELECT"){
          ret = element.value;
        }
        if (ret instanceof Array){
          ret = ret.filter(filterFunction);
          if (ret.length == 1){
            ret = ret[0];
          }else{
            ret = attemptListToObject(ret);
          }
          
          /*else{
            if(tagName == "TD"){
              return ret
            }
            ans = {};
            for (const part of ret){
              ans[Object.keys(part)[0]] = part[Object.keys(part)[0]];
            }
          }
          ret = ans;*/
        }
        if (filterFunction(ret)){
          if (ret instanceof Object){
            let keys = Object.keys(ret);
            if (keys.length == 1 && ( !hasValue(name) || name == Object.keys(ret)[0] )){
              ret = ret[keys[0]];
              name = keys[0];
            }
          }
          if (name !== null){
            let ans = {};
            ans[name] = ret;
            return ans;
          }
          return ret;
        }
      }
      
      let addJson = function(){
        let items = Array.from(document.getElementsByName("orderItem"));
        items.shift();
        //let attributeNames = ["Material","Shape","Dimensions","Top","Front","Face","Left","Right","Back","Certification","Price","Additional Specs"];
        let itemNumber = 0;
        let itemData = {};
        for (const item of items){
          itemNumber++;
          itemData[itemNumber] = yieldData(item);
          //print(yieldData(item));
        }
        //print(itemData);
        let ans = {};
        ans["orderSpec"] = yieldData(document.getElementsByName("clientItem")[1]);
        ans["items"] = itemData;
        let jsonText = JSON.stringify(ans,null,2);
        let json_p = document.createElement("pre");
        json_p.textContent = jsonText;
        document.getElementById("dataView").prepend(document.createElement("hr"));
        document.getElementById("dataView").prepend(json_p);
        window.open("./AddOrder?"+encodeURI(JSON.stringify(ans)));
        return jsonText;
      }