Cannot set headers after they are sent to the client in node js

Question

I am getting this error only when I call get method (Not every time).

Here is my node function which returns me a response.

exports.GetDepartmentList = function (req, res) {
    fs.readFile('./api/tempFiles/department.json', 'utf8', function (err,response) {
        res.status(200).send({
            success: true,
            data: JSON.parse(response)
        });
        return res.json();
        dbConn.close();
    }).catch(function (err) {
        res.status(500).send({
            success: false,
            message: err.message
        });
        return res.json();
        dbConn.close();
    });
};

I already checked all the StackOverflow's questions but none of them are helpful for solving my problem.

Answer 1

This error occured when you send multiple responses to your client side.

I think you should try with something like this (without catch)

exports.GetDepartmentList = function (req, res) {
    fs.readFile('./api/tempFiles/department.json', 'utf8', function (err, response) {
        if (err) {
            res.status(500).json({
                success: false,
                message: err.message
            });
        }
        else {
            res.status(200).json({
                success: true,
                data: JSON.parse(response)
            });
        }
        dbConn.close(); // Really usefull ?
    });
};

Hope it helps.