Using XMPP for Request Response - xmpp

I would like to know if is it possible to get XMPP messages sent by mobile client applications in my PHP Back end server?
The PHP Back end server will process the messages (JSON request) and send responses back to the client mobile apps. There will be 5 million client application users sending messages to server simultaneously.

Well you can use XMPP but definitely for that, you will need alot of changes.
Your mobile clients will send data in XMPP packets (message or iq) and you will have to handle those stanzas and parse them to get the data (which can be JSON).
So, Yes you can use XMPP but you need to have such skills (both on client side and on server side).

Related

Ejabberd Message delivery while application is terminated

I am developing a chat app using ejabberd server for both IOS and Android. I also wrote a module for ejabberd to get the offline messages sent to my own server api .
my own server api will send notifications to the IOS/Android platforms using FCM.
On the client side , if the application is in the foreground or the background , it will stay connected to ejabberd and if the client receives the message then ejabberd will send the message delivery status.
I am facing an issue while the app is terminated ( service is not running ) which means it is not connected to ejabberd (offline) . if i send a message to this app while it is not terminated , it will receive a notification but the message still undelivered . how can mark the messages as delivered when receiving the notification while the app is terminated.
to explain it more , the same functionality is working fine with whatsapp :
device A has whatsapp installed and whatsapp was turned off (terminated)
Device B has whatsapp running
Device B sends a message to device A
Device A receives a whatsapp notification
Without doing anything on Device A , the message status on Device B is marked as delivered .
How can I implement this scenario with ejabberd ?
In case someone went into this issue , here is the solution that I implemented with help of #Mickaël Rémond from his answer.
I configured ejabberd to send the offline messages to an http service ( your own server) please refer to this link for further on how to do it
your server should catch the above call and generate a notification message (FCM ) in my case and send it to recipient device
recipient device will catch the notification which includes the message
recipient device will call http service (your own server backend)that responsible for sending the deliver ack to the original sender . you need to pass from, to , stanzaId , vhost with this call
backend server will use ejabberd-api (set of exposed apis to manage ejabberd through rest apis calls) to send delivery message using this api
please note the following notes also :
sending the delivery message from your own server to ejabberd will not delete them from ejabberd database
if the user re-connected to the ejabberd server then the recipient will receive the message again from ejabberd .
It is probably too complex for a simple Stack Overflow question, as you need to integrate several moving part on client and server:
You need to execute code in background when receiving push notifications on iOS (you need that property set on your app in your app provisioning profile and have code to handle that). The client will initiate an HTTPS query to let the server know that the message was delivered.
You need to have an endpoint that will get the delivered HTTPS calls and generate either a message ack or a chat marker on behalf of the user and route it in ejabberd.
In real world, this is not enough if you want to take into account the fact that you can only have 1 push in the queue on APNS. If you have several messages sent while the device is not on the network, you will need to have the device check all received messages while offline on the server, otherwise you will lose messaging.
You need to rely on XMPP Message Archive Management (MAM) to handle that history.
As you see, this is not a simple few tens of line of codes but need real design and involved work.

Openfire XMPP Bot over Channels

I am using Openfire as an XMPP server for building a customer support Bot framework.
I am planning to make use of channels/groups for the same. I am keen to use channels as there might be multiple human agents and a bot listening to the same conversation. So I am likely to have a group/channel for each individual.
I want the messages to be read and processed by my custom server. How do I go about this ? I couldn't find any plugin that allows me to intercept the messages and return back processed response.
Any recommendations ?
You can also create your an own openfire bot plugin if you are familiar with Java (small example: https://rmsol.de/2018/03/06/Openfire_Bot/). Otherwise create bot as a client lilke dontknow suggested (The "bot/client" will join every channel you like and e.g. listen for specific keywords)
I figured out that since Openfire is an XMPP Communication software, its best to just use a custom XMPP client ( on your own server ) to listen to all the messages and process it from there and reply back from the XMPP Client as well.
So if I have a Nodejs server, I will create a Node XMPP Client and listen to XMPP messages coming via Openfire from other users, will process them and reply back with custom messages which Openfire will send back to the user.

Is it possible to listen/monitor messages send from a user to an another on Openfire Server using Smack API?

is it possible to listen / monitor messages send from a user to an another on Openfire Server using Smack API
No, that would be a privacy violation, because it would mean that a third party is able to intercept and read messages between two JIDs.
Of course, you can modify any XMPP server to relay certain XMPP stanzas to a third party. But since there is no XEP that defines a API for such a mechanism, it's also not available in Smack.

How to send XMPP Message with a given From or ReplyTo?

I would like to initiate a Chat between two users A and B from my web application. So I create an XMPP Message using Smack Client API or directly from an OpenFire Plugin:
Send a Message by Smack from A to B
Send a Message by Smack from Server to B with replyTo A
XEP-0033 allow "replyTo address" supported by OpenFire but not suported by IM Clients.
It seems "from" can't be overrided by a client or an OpenFire plugin. I also think GTalk will not accept an xmpp message from userA#gmail.com to userB#gmail.com by ServerToServer protocol.
Is there an other way to do this ? I want my web application to forge a message from UserA to UserB. But this webapp is not A or B.
Best Regards,
Jp
Any XMPP server should ignore the from address in a stanza and stamp the one that it get's from the connection into the stanza it sends on. This is a specific feature of XMPP compliant servers and is used to stop address spoofing and spam etc. You'd probably have to edit the source of a server and change it's behaviour. This is dangerous though and I wouldn't reccomend it if you'll be federating with other servers.
J

Send XMPP message without starting a chat

I am basically writing a XMPP client to automatically reply to "specific" chat messages.
My setup is like this:
I have pidgin running on my machine configured to run with an account x#xyz.com.
I have my own jabber client configured to run with the same account x#xyz.com.
There could be other XMPP clients .
Here is my requirement:
I am trying to automate certain kind of messages that I receive on gtalk. So whenever I receive a specific message eg: "How are you" , my own XMPP client should reply automatically with say "fine". How are you". All messages sent (before and after my client replies) to x#xyz.com but should be received by all clients (my own client does not have a UI and can only respond to specific messages.).
Now I have already coded my client to reply automatically. This works fine. But the problem I am facing is that as soon as I reply (I use the smack library), all subsequent messages that are sent to x#xyz.com are received only by my XMPP client. This is obviously a problem as my own client is quite dump and does not have a UI, so I don't get to see the rest of the messages sent to me, thereby making me "lose" messages.
I have observed the same behavior with other XMPP clients as well. Now the question is, is this is a requirement of XMPP (I am sorry but I haven't read XMPP protocol too well). Is it possible to code an XMPP client to send a reply to a user and still be able to receive all subsequent messages in all clients currently listening for messages? Making my client a full fledged XMPP client is a solution, but I don't want to go that route.
I hope my question is clear.
You may have to set a negative presence priority for your bot..
First thing to know is that in XMPP protocol every client is supposed to have a full JID. This is a bare JID - in your case x#xyz.com with a resource in the end e.g. x#xyz.com/pidgin or x#xyz.com/home (where /pidgin and /home are the resource). This is a part of how routing messages to different clients is supposed to be achieved.
Then there are the presence stanzas. When going online a client usually sends a presence stanza to the server. This informs about e.g. if the client is available for chat or away for lunch. Along with this information can be sent a priority. When there are more than one clients connected the one with the highest priority will receive the messages sent to the bare JID (e.g. ClientA(prio=50) and ClientB(prio=60) -> ClientB receives the messages sent to x#xyz.com). But there are also negative priorities. A priority less than 0 states that this client should never be sent any messages. Such a stanza might look like this
<presence from="x#xyz.com/bot">
<priority>-1</priority>
</presence>
This may fit your case. Please keep in mind it also depends on the XMPP server where your account is located, which may or may have not fully implemented this part of the protocol.
So to summarize: I recommend you to look through the Smack API how to set a presence and set the priority to <0 for your bot client right after it connected.