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I am using passportJS for authentication. If user get register, I create token for the user but the issue is I can't modify or change the object eg.

Code:

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exports.register = function( req, res, callback )
{
    passport.authenticate( 'local-signup', function( err, user, message )
    {
        if ( err )
            return callback( err );

        if ( !user )
        return callback( {status: 400, message: message} );

    autorization.createToken( user, function( err, token )
    {
        if (err)
            return callback(err);
        var userData = {}; //<Issue is its not editable I can't append or delete from this.>
        userData = user;
        delete userData.password;
        userData["token"] = token;
        console.log(userData);
        console.log(token);
        return callback(null, user);
    } );
} ) ( req, res, callback );
};

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Now issue is though token is generating. I am received token in callback. but I can't change value for user object that is return. What I want is once token is created it append on key token and returns to user.

Code:

---

exports.createToken = function( user, callback )
{
    var token = jwt.sign( //        { _id: user._id, email: user.email, password: user.password}
                    user, config.superSecret, {
                    expiresInMinutes: config.expJwtMin
    } );
   
    return callback( null, token );

};

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