Save json string to client pc (using HTML5 API)

I read few older thread about the same, but seen the file API changed a lot recently. My requirement is to save a json file (data is locally in indexdDB, but I need a way to back it up). Since I use indexdDB, I only target recent browsers, mainly chrome. So, it it possible to save data (json string) to client computer?

I have seen http://eligrey.com/demos/FileSaver.js/ , but is there a way to do it natively?

Thanks.

Answer

You can use a Blob and the HTML5 a[download] feature to provide a JSON backup download:

var data = {a:1, b:2, c:3};
var json = JSON.stringify(data);
var blob = new Blob([json], {type: "application/json"});
var url  = URL.createObjectURL(blob);

var a = document.createElement('a');
a.download    = "backup.json";
a.href        = url;
a.textContent = "Download backup.json";

Here is a jsfiddle example: http://jsfiddle.net/potatosalad/yuM2N/