integrating own users with xmpp chat client using Smack - android

I am fiddling with Smack on Android and utterly confused as to how to integrate my own database users with this XMPP client. From what I understood, XMPP has its own notion of users and groups with their login credentials. Also, they have helper objects for Chat and ChatManager.
I have my own database of users, and chat messages which I want to store at my server and device. Let us say the user has id - id1. Now:
how do i authenticate the user, i mean what would be the credentials.
how to listen to the incoming messages for the current user.
can i use REST interface to send chat messages to my server and not through XMPP client - in that case would the above listener would still work ?
Using smack - do i still get the control to manage what object i use for Chat message for communication between my server and client.
Basically, I think I am not able to visualize the stuff happening behind the scenes at server (or how to implement it ). Can some one please explain the very basics or point to me in the right direction.

You need to have XMPP server application (ejabberd, prosody, openfire, tigase, etc.) to authenticate users. Most of XMPP servers are able to authenticate users against your own user database/REST API, or you can write simple plugin/script. You can write your own XMPP server too, but it may be too complex task.
Smack documentation provide useful messaging examples
Your REST interface may send XMPP messages too, or you may need to write additional XMPP server plugins to monitor new messages in your database, depends on your service architecture
Your can extend XMPP message as you like, just keep your extended message fields in your own XML namespace. Of course, you may need to extend XMPP library both on client and server to support these new message elements.

Related

One to One Android Chat using Firebase

I need some clarifications.
I'm using Firebase realtime database.
Now I've to implement a realtime chat between two android devices. I need also push notifications.
So, the solution based on realtime database is to drop because if the app isn't running, it will not handle the onChildAdded event.
I read on the documentation that I can achieve my aim, using the upstream message from the device to the server.
Now, it's written also that we need an app server.
I just want to be clarified the need of the app server (XMPP or HTTP), and which is the entire flow of message m1 sent from the device A, and the notification on the device B.
In my opinion the app server should act as a man in the middle, so:
A ---> XMPP SERVER ---> FCM
FCM ---> XMPP SERVER ---> B
Is this the flow?
On the documentation I can't understand if I'm right or not.
If so, how do I send a message from the FCM back to the XMPP Server?
The notification message is sent from FCM to the client o from XMPP Server?
Please someone clarify me.
Other solution thought by me:
Since I find really powerful firebase realtime database, I thought these solution to walk around the problem:
Create an app server the is listening for onChildAdded and when it changes send a notification to client device.
Creating a background service on the client app listening to onChildAdded and create notification when necessary.
Even all, I don't like these solutions.
Just want to understand the standard and correct way to achieve my aim.
Firebaser and author of the article debated in the question comments here
To send messages to a device with Firebase Cloud Messaging, you need to specify your project's FCM Server Key. As its name suggests, this key should only be used in code that runs in a trusted environment: i.e. a server that you control.
To send device-to-device messages (such as in a 1:1 chat application where the receiving user is not necessarily online) you need two steps:
one user send an upstream message
the other user receives the downstream message
Using Firebase Cloud Messaging and your custom app server code, you can handle step 2. But that still leaves step 1: the user needs to send a message that somehow triggers your code on the app server. There are quite a few ways to do this.
For example you could implement an HTTP endpoint on your app server and have the chat application send the messages there too (in addition to sending to the database).
You could also implement an XMPP endpoint and have the chat application send the message there (again in addition to sending it to the database).
My article suggest yet another way, one that doesn't require implementing an endpoint at all. It uses a node.js script that runs on your app server and is essentially just a client to the database. Whenever this script detects a relevant chat message, it calls the FCM API and sends the downstream message.
This pattern of using the Firebase Database as your endpoint and then using server-side scripts is quite common when using Firebase. We documented it in our classic blog post Where does Firebase fit in your app? (as option 2) and in this article in the Google Cloud documentation.

Do XMPP Servers (Openfire) require implementations?

Do XMPP Servers such as Openfire require implementation of their own in order to handle messages. Do I need a web language such as PHP in order to handle messages with Openfire?
Because according to posts such as this How to make Chat Application in Android Using XMPP and GCM, I do not need to write PHP scripts in order to handle messages, Openfire (it being a XMPP server) will do all the heavy lifting. So when creating a messaging program is the only thing I need to worry about the client side code?
I've also run into contradictory information that I hope someone can clarify on. It was to my knowledge that one needed to use a XMPP server along side GCM; as GCM is not reliable in delivering messages by itself and requires an XMPP server to fully be reliable. Is this true, the above link suggests that it isn't, but according to this it is https://www.youtube.com/watch?v=5wXGcu9H91s
Some clarification would be great, thanks.
GCM allows you to use both HTTP and XMPP to send messages down from your application server through GCM to your devices.
Only with XMPP though can you send messages from your device through GCM to your server. This allows your device to send acknowledgment messages back up to your server. This does not necessarily make GCM more reliable but it does allow you to have a better audit of what messages were actually received by devices.
Openfire is a server that supports XMPP so you will still have to implement the protocol maybe using Smack.
Note that you could skip GCM and have a connection directly between your app and your XMPP server, however this is not recommended since your app would have to be constantly connected to your server which would be very hard on the battery of the device. This is where GCM comes in, allowing your app to receive messages even when it is in the background but still being kind to the battery of the device.

XMPP GCM Android implementation guidance

I have been working on GCM xmpp implementation for my chat functionality, but about a week, I am not getting online help to start with , I have got this XMPP GCM Android tutorial, but I see xmpp is not fully implemented, and upon seeing their code, it is very unclear to understand the functionality
firstly. my current structure is
Android client app for chat functionality.
java backend, app server jboss hosted in openshift cloud platform.
and according to this google gcm-xmpp image.. I see client interacts directly to gcm, which I get confused, intern gcm connects app server.
as per my implementation, I get gcm regid from gcm and send http request to app server which intern send notifications to client devices through gcm. this is reverse of what we see with gcm flow diagram
secondly, since I have already set up app server Jboss, which can handle http request for my client request other than chat functionality. now I need to implement xmpp for handling asynchronous, bidirectional, upstream messaging with another servers like openfire or ejabberd which supports xmpp.
currently I am in state where I don't know how to start with xmpp, I have got above queries, in the hope getting some directions to start with.

How Can An App Communicate With a Server and reflect updates immediatly?

hi this is just for knowledge. i will try to explain as much as i can what is my question.
Usually i call on an Async Service every amount of time i.e updates on the server part for example are not reflected as soon as they change. whatsapp for example reflects the updates almost instantly. for example when a user is typing, it shows to the other user that he is typing.
In short what protocols do they use and how do they use it.
thank you.
What protocols do they use?
Application like Whats app,G-talk ,facebook etc they uses XMPP protocol for IM services.
What is XMPP?
The Extensible Messaging and Presence Protocol (XMPP) is an open
technology for real-time communication, using the Extensible Markup
Language (XML) as the base format for exchanging information. In
essence, XMPP provides a way to send small pieces of XML from one
entity to another in close to real time
As per latest version of specifications XMPP provides below services
Channel encryption [RFC3920]
Authentication [RFC3920]
Presence [RFC3921]
Contact lists [RFC3921]
One-to-one messaging [RFC3920]
Multi-party messaging [XEP-0045]
Notifications [XEP-0060]
Service discovery [XEP-0030]
Capabilities advertisement [XEP-0115]
Structured data forms [XEP-0004]
Workflow management [XEP-0050]
Peer-to-peer media sessions [XEP-0166]
This are the core services available in XMPP
Below are some Applications where XMPP can be used
Instant messaging
Groupchat
Gaming
Systems control
Geolocation
Middleware and cloud computing
Data syndication
Voice over IP (VoIP)
Identity services
Like HTTP XMPP also require server-client implementation
Below are some popular XMPP servers
Ejabberd
Openfire
Prosody
Tigase
You can find more information on xmpp server on this link
Different platform has their different XMPP client library you can more information on this link
If you want to implement XMPP client for android then you can use Smack 4.1 ,it is an open source XMPP client library written in java.
I have tried to list down basic feature of XMPP here but if you getting started with xmpp ,then there are lost of things to learn , free to ask any doubt regarding XMPP I will try my best .
Thank you
Note::
for the user who are still using aSmack should Upgrade to Smack 4.1 as aSmack has been deprecated!!
aSmack Deprecation Notice
aSmack to Smack Upgrade guide
You could implement the Google Cloud Messaging (GCM) service, as the GCM site says:
Google Cloud Messaging (GCM) for Android is a service that allows you
to send data from your server to your users' Android-powered device,
and also to receive messages from devices on the same connection...
This way you can inform from one client a status change, the backend then send the propper message to the desired clients and finally those clients app updates the status.
https://developer.android.com/google/gcm/index.html

GCM server direct from android app

I am creating a chat application on android using GCM. I'm already able do receive messages from the cloud and to send them manually through a PHP script using cURL. I can simple make an HTTPRequest to this script everytime a user send a message but I would like to know if there's a way to remove this script thus making the android app directly send the message to the cloud. If this is possible I also would like to know if it is the "right" way to do it or if the HTTPRequest is as good as it.
Thanks in advance.
Not really. GCM is not meant to replace your entire infrastructure, just the push channel from your servers to the clients.
That said, there is this concept of Upstream Messaging (from device to Google's servers) but Google's servers then contact your servers (via XMPP of all things) to let you decide what to do next.
You cannot do device-to-device over GCM.

Categories

Resources