node js util promisify

The util.promisify method in Node.js is used to convert a function that uses callbacks into a function that returns a promise. Here is an explanation of each step involved in using util.promisify:

1. Import the util module: The util module is a built-in module in Node.js that provides various utility functions. To use the promisify method, you need to import the util module into your code.

2. Access the promisify method: Once the util module is imported, you can access the promisify method using util.promisify. This method takes a function as its parameter and returns a new function that returns a promise.

3. Pass the function to promisify: To convert a function that uses callbacks into a function that returns a promise, you need to pass the original function as a parameter to the promisify method. The original function should follow the Node.js callback convention, where the last parameter of the function is a callback function with the signature function(err, result).

4. Obtain the promisified function: The promisify method will return a new function that wraps the original function and returns a promise instead of using callbacks. This new function can be assigned to a variable for later use.

5. Use the promisified function: The promisified function can now be used like any other function that returns a promise. You can use the then and catch methods to handle the resolved value or any errors that occur during the execution of the function.

By using the util.promisify method, you can simplify the usage of functions that rely on callbacks and leverage the power of promises in your Node.js applications.