Openfire | XMPP server licensed under the Open Source Apache License | Chat library

Finally I solved the problem by changing the Domain name to be exactly as the IP address of the server (previously I set it to be xmpp) and then using test instead of test@xmpp as username.

By using the annotation PropertySource

If file within classpath:

That was nothing but restart openfire and follow again. There will be no error.

I don't see the purpose of using a for-loop for this:

When calculating the response, the third line concatenates the buffer y (which contains an MD5 hash) with strings, whereby y is implicitly converted to a string using UTF-8.
However, an arbitrary byte sequence, such as a hash, will be corrupted by a UTF8 encoding, s. here. To prevent this, the individual parts should be concatenated as buffers rather than strings.
In contrast, the remaining concatenations (in this and the other lines) are not critical, since they are true strings:

Ok, I finally did it. For the others that could face the same issue, I was focusing just on the reMessage function while the problem was on the onConnect function, indeed I used .bind(this) on that particular function and everything went fine.

Best library depends on your use case, try SleekXMPP following the examples here. You may also want try aioxmpp which provides easy to use APIs. Or you can just try start from simple examples like this using xmpp and build on it.

My suggestion is try these clients, go with whichever does the job for what you want to achieve. I would prefer SleekXMPP just because I tried it and it did the job for what I wanted it for, it also has a better documentation and many examples. But aioxmpp is also something I would like to try.

I found the answer. I just updated my Chat object. The imported class was wrong previously. Now it's corrected with the following line.

Disclaimer: I'm on the MongooseIM core team.

There are multiple ways this could be achieved. The easiest way to achieve this depends on your familiarity with Erlang, the programming language MongooseIM is written in.

1. You won't need any Erlang to use the event pusher module with its HTTP backend and the default settings, but you'd need some Erlang to control what messages get forwarded to the HTTP service or to make more complex setups. To send messages back, you'd either need to use the MongooseIM REST API or connect as an ordinary XMPP client to the server using one of the many XMPP libs available out there. This is probably the best approach to achieve your goal.
2. You can skip using the event pusher and just connect your bot as an XMPP client written in any language whatsoever. The bot might have your business logic within or can forward messages it gets to the HTTP service.
3. If you're comfortable working in Erlang, then the mechanism to extend the server is called Hooks and handlers and is described in the official MongooseIM documentation. This requires writing code in Erlang and building from source, but does not necessarily require modifying upstream MongooseIM code.
4. You could use the XMPP component protocol, which allows to extend the functionality of an XMPP server, yet structure it as multiple services. The components may be written in any technology you want and the most popular XMPP libraries should support the component protocol out of the box.

Depending on your choice from the above list and the language and environment you prefer, you might have to pick an XMPP library to use. There are XMPP libs available for iOS (ObjC and Swift), Android (Java and Kotlin), Python, JavaScript, C, and even some emerging ones for Rust, Dart and possibly more.