I need some help. I need to fetch what the file type should be from the file containing only using Node.js. I am explaining the scenario below.

Let's say I have some content like below.

let fileContent = "The textContent property sets or returns the text content of the specified node, and all its descendants."

As we can see here the variable fileContent has some text data and I want to write this data into one file. So for that, I need to create the file with a proper extension like abc.txt. Similarly, If fileContent has some json data then I will create the file like abc.json and write the value inside it.

So here I need to fetch what should be the type of file from this content only using Node.js. If anybody has a solution for this will be a great help.