Office 365 - Create *.docx | *.pptx | *.xlsx files

I'm working on a web project which uses the OneDrive API for file management purposes. I wanted to create *.docx | *.pptx | *.xlsx files but unfortunately, none of the OneDrive APIs support creating empty files. What I tried was to upload an empty file from my server to OneDrive. While the upload works fine, the file does not open in Office Online nor in local Office.

From this blog, I was able to generate a Word file and upload it.

function createNewDoc(name) {
var htmlString = "<html><body></body></html>";
var byteNumbers = new Uint8Array(htmlString.length);

for (var i = 0; i < htmlString.length; i++) {
   byteNumbers[i] = htmlString.charCodeAt(i);
    }
    var blob = new Blob([byteNumbers], {type: "text/html"});
    socialAPI.uploadFile('windows', blob, 'name', 'folder.87ash7ashb7a2').then(function (resp) {
        console.log("response for uploading file", resp);
    })
}

This file worked for Word. However, the method doesn't work for Excel and Powerpoint.

So ultimately, I was not able to do anything using the OneDrive API. I started looking at Office 365 API if there's anything which allows creation of above mentioned files but I couldn't find anything like that. (P.S: I'm looking at REST APIs)

Another thing I noticed is Box is able to do the same and open it in a window, but the url is in the format https://app.box.com/services/box_for_office_online. Does Box have some special collaboration with Microsoft to provide such a service?