Express Validator, one function that will check multiple forms - node.js

Question

I have been attempting to use Express Validator, however I have come across a problem.
Currently, I am using one route with a variable (which is the action, e.g update name, email, password etc.) to send the updated user data to the server.
I am using a switch statement that looks at the action, and does the relevant update to the user data.
I'd like one validation function that also has a switch statement, which will determine what it needs to validate.
Currently I have this so far...
this validation rules:
const validationRules = () => {
console.log("validating...");
return [
// names must be 1 or more
body("firstName").isLength({ min: 1 }),
body("lastName").isLength({ min: 1 }),
];
};
the post request:
app.post(
"/api/user/update/:action",
validationRules(),
validate,
(req, res) => {
const { id } = req.body;
const { action } = req.params;
const updateDatabase = (id, updateObject) => {
UserModel.findOneAndUpdate(
{ _id: id },
{ $set: updateObject },
{
useFindAndModify: false,
}
)
.then((user) => {
console.log(user);
res.sendStatus(200);
})
.catch((err) => {
console.log(err);
res.status(403).send({ error: err });
});
};
const errors = validationResult(req);
if (!errors.isEmpty()) {
return res.status(422).json({ errors: errors.array() });
} else {
let update = {};
switch (action) {
case "name":
const { firstName, lastName } = req.body;
update = {
"userInfo.firstName": firstName,
"userInfo.lastName": lastName,
};
break;
case "email":
const { email } = req.body;
console.log(email);
update = {
"userInfo.email": email,
};
break;
case "mobile":
const { mobile } = req.body;
update = {
"userInfo.mobile": mobile,
};
break;
default:
console.log("nothing matched so nothing updated");
break;
}
updateDatabase(id, update);
}
}
);

Answer 1

You can make a simple middlware and the switch case there:
Here is an example:
const app = require('express')();
const validatorMiddleware = (req, res, next)=>{
switch(req.params.action){
case 'foo':
//here you will `return` the rules
console.log('foo');
break;
case 'bar':
//here you will `return` the rules
console.log('bar');
break;
default: console.log("default");
}
next();
}
app.get('/:action', validatorMiddleware, (req, res)=>{
res.send(req.params);
})
app.listen(8080, ()=>{
console.log('started');
})
For your case it will be something like this:
const validationRules = (req, res, next) => {
console.log("validating...");
switch (req.params.action) {
case "name":
return [
// names must be 1 or more
body("firstName").isLength({ min: 1 }),
body("lastName").isLength({ min: 1 }),
];
}
next();
};