node.js | Redis cache loading old data - node.js

Question

I am trying to setup a mongo, node and redis server and all is working well other than the Redis cache which seemingly loads the older data.
Taking Redis out and using pure Mongo returns the right data, and if I click submit again it will load the data from the previous submission, so I know the cache and Mongo is updating fine.
This is the current code I have for updating the user using Mongo and Redis...
updateUserById: (newUser, redis, id, callback) => {
User.findByIdAndUpdate(id, {
$set: {
"firstName": newUser.firstName,
"lastName": newUser.lastName,
"email": newUser.email
}
}, (err, doc) => {
if (err) { throw new Error(err); }
else if (!doc) { callback('No user with that ID to update cache.') }
else {
redis.set(id, JSON.stringify(doc), (err) => {
console.log('Caching updated user ' + id);
if (err) { callback(err); throw new Error(err); }
else {
const result = {
"success": "true",
"message": "User updated successfully"
};
callback(result);
}
})
}
});
}
And this is the redis and Mongo to return the user information...
userById: async (redis, id, callback) => {
redis.get(id, async (err, reply) => {
if (err) {
callback(null); throw new Error(err);
} else if (reply) {
callback(JSON.parse(reply));
} else {
await User.findById(id, (err, doc) => {
if (err || !doc) { callback(null); throw new Error(err); }
else {
redis.set(id, JSON.stringify(doc), () => {
callback(doc);
})
}
})
}
})
}
I have found out it's something to do with the doc containing the old information in the updateUserById

Answer 1

The issue was inside of the update method.
When the doc was being passed, it was being passed the old data not the new data. To counter act this I used the newUser which was passed into the method.
Here is the updated code:
updateUserById: (newUser, redis, id, callback) => {
User.findByIdAndUpdate(id, newUser, (err) => {
if (err) { throw new Error(err); }
else {
redis.set(id, JSON.stringify(newUser), (err) => {
console.log('Caching updated user ' + id);
if (err) { callback(err); throw new Error(err); }
else {
const result = {
"success": "true",
"message": "User updated successfully"
};
callback(result);
}
})
}
});
}

Answer 2

Using new option can be useful to return new document.
Mongo return old document by default after update.
To return new document mongo option new may be useful
usage: Model.findByIdAndUpdate(id, update, {new: true});
updateUserById: (newUser, redis, id, callback) => {
User.findByIdAndUpdate(id, {
$set: {
"firstName": newUser.firstName,
"lastName": newUser.lastName,
"email": newUser.email
}
},{ new : true }, (err, doc) => {
if (err) { throw new Error(err); }
else if (!doc) { callback('No user with that ID to update cache.') }
else {
redis.set(id, JSON.stringify(doc), (err) => {
console.log('Caching updated user ' + id);
if (err) { callback(err); throw new Error(err); }
else {
const result = {
"success": "true",
"message": "User updated successfully"
};
callback(result);
}
})
}
});
}