Node js remove sensitive data from object before sending it

Question

I want to remove some sensitive data from the array before sending to the client (to render all the users), but for some reason I can't actually remove them! I need to remove some usernames, passwords, emails etc. Is there something with splice() ? Thank you for helping me!

app.get('/users', function(req, res){ Users.find{}, function(err, usersArray){
  for(var a = 0; a < usersArray.length; a++){
    usersArray[a].userData.username.splice(0, 1); // here's my error
    usersArray[a].userData.email.splice(0, 1); // end here
    usersArray[a].userData.password.splice(0, 1); // and also here
    ...
  }
  res.render('users.ejs', {
    // and the variables go here...
  })

}

By the way, the error I get is "TypeError: undefined is not a function". Thanks again!

Answer 1

I'll take a wild guess that you want to remove username , email , and password entirely. If so, you're looking for delete , which removes properties from objects:

app.get('/users', function(req, res){ Users.find{}, function(err, usersArray){
  for(var a = 0; a < usersArray.length; a++){
    var userData = usersArray[a].userData;
    delete userData.username;
    delete userData.email;
    delete userData.password;
    ...
  }
  res.render('users.ejs', {
    // and the variables go here...
  })
}

If those propeties are non-configurable , delete can't remove them, and you have to make do with setting their values to undefined :

app.get('/users', function(req, res){ Users.find{}, function(err, usersArray){
  for(var a = 0; a < usersArray.length; a++){
    var userData = usersArray[a].userData;
    userData.username = undefined;
    userData.email = undefined;
    userData.password = undefined;
    ...
  }
  res.render('users.ejs', {
    // and the variables go here...
  })
}

If they're both non-configurable and non-writable, you'll have to create replacement objects instead.

Live Example using delete :

 var usersArray = [{ userData: { name: "User 1", // Something to have left after we remove the others username: "user1", email: "user1@example.com", password: "pa$$word" } }, { userData: { name: "User 2", username: "user2", email: "user2@example.com", password: "pa$$word" } }, { userData: { name: "User 3", username: "user3", email: "user3@example.com", password: "pa$$word" } }]; snippet.log("Before: " + JSON.stringify(usersArray, null, 2)); for (var a = 0; a < usersArray.length; a++) { var userData = usersArray[a].userData; delete userData.username; delete userData.email; delete userData.password; } snippet.log("After: " + JSON.stringify(usersArray, null, 2));

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Live Example with non-configurable properties using undefined :

 function makeUserData(name, username, email, password) { var ud = {name: name}; Object.defineProperty(ud, "username", { enumerable: true, configurable: false, writable: true, value: username }); Object.defineProperty(ud, "email", { enumerable: true, configurable: false, writable: true, value: email }); Object.defineProperty(ud, "password", { enumerable: true, configurable: false, writable: true, value: password }); return ud; } var usersArray = [{ userData: makeUserData("User 1", "user1", "user1@example.com", "pa$$word") },{ userData: makeUserData("User 2", "user2", "user2@example.com", "pa$$word") },{ userData: makeUserData("User 3", "user3", "user3@example.com", "pa$$word") }]; snippet.log("Before: " + JSON.stringify(usersArray, null, 2)); for (var a = 0; a < usersArray.length; a++) { var userData = usersArray[a].userData; delete userData.username; delete userData.email; delete userData.password; } snippet.log("After delete: " + JSON.stringify(usersArray, null, 2)); for (var a = 0; a < usersArray.length; a++) { var userData = usersArray[a].userData; userData.username = undefined; userData.email = undefined; userData.password = undefined; } snippet.log("After assigning undefined: " + JSON.stringify(usersArray, null, 2));

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