Comparing two uuids in Node.js

Question

I have a question I was not able to find any answer with my research on the web. I work on a web application in Node.js and Cassandra. I'm currently working on a notification system and I have to compare two uuids to make sure I don't send a notification to the people who make the original action ( which provoke the notification ).

The problem is that, when I compare two uuids which are supposed to be equals, I always get a false value.

Here is the example of code I'm currently working on :

console.log('user_id :', user_id.user_id);
console.log("user id of the current user :", this.user_id);

console.log(user_id.user_id == this.user_id);
console.log(user_id.user_id === this.user_id);

And here is the display of the result :

user_id : Uuid: 29f1227d-58dd-4ddb-b0fa-19b7fc02fbe8
user id of the current user : Uuid: 29f1227d-58dd-4ddb-b0fa-19b7fc02fbe8
false
false
user_id : Uuid: c8f9c196-2d63-4cf0-b388-f11bfb1a476b
user id of the current user : Uuid: 29f1227d-58dd-4ddb-b0fa-19b7fc02fbe8
false
false

As you can see, the first uuids are supposed to be the same. They are generated with the uuid library inside the nodejs cassandra driver. I don't understand why I can not compare them when I am able to make any request on my Cassandra database with a uuid specified.

If someone could help me, it will be a great pleasure !

Answer 1

As Ary mentioned, the contents are the same but the addresses are not, so the comparison returns false.

The cassandra-driver's UUID object provides an equals function which compares the raw hex string of the contents of the UUID that you could use for this:

> var uuid1 = uuid.fromString('29f1227d-58dd-4ddb-b0fa-19b7fc02fbe8')
> var uuid2 = uuid.fromString('29f1227d-58dd-4ddb-b0fa-19b7fc02fbe8')
> uuid1 == uuid2
false
> uuid1 === uuid2
false
> uuid1.equals(uuid2)
true

Answer 2

The content is the same but their addresses should not be. If your comparaison returns false it may be your variables are Object type.