The following is a simple piece of code to reduce the workload to merge code
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <meta http-equiv="X-UA-Compatible" content="ie=edge"> <title>Document</title> </head> <body> <script> let BIG = {};let SM = {}; let BIGObj = JSON.parse(JSON.stringify(BIG)) let SMObj = JSON.parse(JSON.stringify(SM)) for(var key in SMObj) { if(!BIGObj[key]){ BIGObj[key] = SMObj[key] } if(SMObj[key] instanceof Object){ for(var a in SMObj[key]){ if(!BIGObj[key][a]){ BIGObj[key][a] = SMObj[key][a] } } } } console.log(JSON.stringify(BIGObj)) </script> </body> </html>