I'm currently creating a web app. The app goes like this, the client creates something like reports in the web app, and we are using html5 and php and mariadb w/ phpmyadmin for our front end and database. And then, the report will send to the server. And the admin of the server will give response to the report. Now I am wondering on how the admin will response. Should I create a new webpage for the admin so he can receive the report? Should I use websocket? or is there something else? Any idea? Thank you very much in advance.
Since a web page report submission is inherently asynchronous (ie you don't know when it will occur), it follows that the admin response to submitted reports should also be asynchronous (since admins have to go to the toilet every now and then, much to the chagrin of management).
Your report system should post the report to a queue of 'to-be-processed' inbound reports. The admin could have either a web page portal (or a custom native applicatoin) for viewing pending reports. From there the admin can select one, view it, send client an update, close it. in other words, whatever host of actions the admin is expected to perform.
In this manner you can have a super admin interface that monitors one or more admins responding to reports and offers a higher level view of all the pending reports (time on queue) and the number of closed reports per admin per hour/day .. you could even make a graph..everyone likes graphs.
hope that helps.
Related
I'm making a website which is going to have different chatrooms. Any user can create a chatroom at any time, and another user may join a chatroom when it is available. Max two users can chat in a single chatroom at the same time, but multiple chatrooms can exist.
I'm using AngularJS and PHP, with the PubNub API for the chat functionality. The created chatroom will be stored in a MySQL database, with the following fields:
User1: the user who created the chatroom. It may change or be null if it leaves.
User2: it will be null at first place and will store the user's name of the person who joins the chatroom.
Closed: when both users are offline, it will be true (1), then nobody can join anymore.
I have to update the columns "user1" or "user2" when any of the users leaves the chatroom. Then, check if both users are offline and then update the closed value.
I know that I can save the user's last connection by calling a PHP function via AJAX every 60 seconds, for example. Even I could check if the other user is still online by checking his last connection in the same function, but who is going to call the function to check if the last user left?
I wonder if I have to do that verification every time either any users request the available chatlists or I have to resolve it with another approach.
I guess that I can set a timeout function in PHP each time a user joins/creates a chatroom. That function is going to update the user column to null and update the closed value if both are null. When the user is in the chatroom, each 60 seconds another function will be called to postpone the first one. But I don't know if it is possible, and if it is possible using shared hosting.
I hope you can help me and thank you very much for your attention.
PubNub Presence: Realtime vs Polling
The answer is - do not poll for presence, instead, have your server listen for changes in channel presence using PubNub Presence Web Hooks. Please read this article thoroughly as it details all the aspects of PubNub's Presence Web Hooks and then review the official documentation for PubNub Presence Web Hooks. The sample code for implementing the REST endpoint on your server to receive the web hooks is Node but you can use that code to implement that in PHP if required but if you can use Node for this purpose, it might be a better choice (and you could still use PHP for everything else).
I know your server has a chat room creation process that inserts new chat room record in your database so you don't need to know when the channel becomes active, but when user1 subscribes to the chat room channel, PubNub will send a channel active event via a web hook to your server, if you need to know when that happens.
When user2 subscribes to user1's chat room channel, PubNub will send a join event to your server via web hook and your server can use that event to update your database with user2's information.
Simultaneously, user1 and user2 will subscribe to the chat room channel and monitor presence (rather than poll with hereNow) and receive the join events, as well. When either user leaves the chat room (unsubscribes from the channel) PubNub will send a leave event via web hook to your server and directly to the user that is still subscribed.
Once the last user leaves the chat room, PubNub will send a channel inactive event to your server and your server can invoke its chat room closed process to update your database as required.
This is a fairly high level design and there are some other details to consider but the message here is do not poll PubNub for presence information. Only use hereNow to get the current state of presence of a channel and listen for further presence events from that point forward either via web hooks to your server or via presence/subscribe to your clients apps. In implementation, you actually subscribe with presence (listen for presence events) and then call hereNow.
For a more detailed discussion of your requirements as it pertains to PubNub, I would recommend contacting PubNub Support to put you in touch with a Customer Success Manager and Solution Architect.
I have an app where basically players challenge each other. At some point their challenge completes and I need to provide them (both of them - there are two players) with an update message, like 'Hey, you won and got 100500 points'. And vice versa - "Hey You looose"
I use websockets and pusher api to tackle the live updates, this works perfectly when player is "online". But what if they are not? The way to go for me looks like I can still handle the event with pusher and instead just displaying the message, I can store it to db to table challenge_notifications with fields messages and seen = 0. it's ok, but what would be the best way then to show this to the player when he comes online next time? I don't want to have ajax request on every page load checking to see if there are any unseen notifications for the user.
I probably somehow need to fetch all pending notifications only once, when they get online?
I use Laravel 5 for my backend.
There was a recent post on the Pusher blog about how to detect if a user is online or not using the Pusher HTTP API: Enabling Smart Notifications with Pusher and SendGrid.
The example uses SendGrid, but you could instead store the update to a database, send them a Push Notification, an SMS etc.
what would be the best way then to show this to the player when he comes online next time?
I guess there are two forms of "coming online":
The user is no longer on the site and has to navigate to the site. In that case as the page loads you can query the DB and serve them up any missed notifications directly (this would seem the easiest solution). Or, if it fits your app architecture, make a single AJAX request when the page loads to get any missed notifications.
If the user has gone offline due to them being mobile or having a bad network connection. In that case you can bind to the connected event using pusher.connection.bind('connected', function() {}); and then make a query to see if they've missed any notifications.
In summary: it would seem that querying the DB for any missed notifications upon normal page render (on the server) would be the simplest solution and wouldn't required much resource usage. But there are alternative mechanisms of delivering a notifications (email, SMS) if they're not online.
I could make an AJAX request that displays the online users for each user. The request is done every 5-10 sec. or whatever. The problem is, isn't that overloading my server too much? Is there a way to do it that it will update the online users for everyone else instantly?
If you are looking for a system that can be used to indicate "Presence" events (Join/Leave/Is Typing/Geo/Lat/Long/etc) in real-time, you should check out PubNub:
http://www.pubnub.com/
Of specific interest to you would be the publish, subscribe, presence, and state APIs.
Both PHP and JS client SDKs are available:
https://github.com/pubnub/php
http://www.pubnub.com/docs/javascript/javascript-sdk.html
geremy
I have a website running on shared server with apache/mysql/php. Each of the pages of the site belongs to one registered user and this user,once logged in can edit the page. Other users that are not owners of the page can only look at these pages but cannot do anything else.
Now I'm planning to add chat functionality to my application. The basic idea is that if owner of the page opens it in a browser, and is logged in, he will be shown for other users (that will be anonymous) as "available for chat". Other users visiting the page will be able to send him messages and vice versa. Anonymous users do not need to communicate with each other and they can communicate only with registered user (owner of the page). So basic structure would be like that:
anonymous user(s) visits the page. Registered owner of the page is not looking at the same page and chat is not available.
Registered owner logs in and opens his page in a browser. All registered users in real time are informed owner is available for chat now.
Anonymous users can send him messages.
Registered user receives the messages and can respond back to each user
Other users can join and chat with registered user any time. It all happens in real time and registered user can see who comes in to visit his page and goes away.
Now, in step 3 and 4 I need to know if the registered user is still logged in. If so then the messages can be passed further to intended user. If not then instead I need to send a message that the owner (registered user) is no longer available for chat.
I'm looking for advice on how to best implement it:
using old school php and ajax calls. So every user would send ajax request every second or so to server and server would keep track of each conversation somehow. Relatively easy to implement I think. I'm not expecting large number of users but I can imagine this would be heavy on the server.
using node.js.
Now my questions:
What could be possible problem with solution 1 above. Would that be too heavy on a server constantly throwing ajax requests at it? would would be reasonable number of users I could accept?
Using node js on my shared hosting.. assuming its possible to install it and run it on separate port, how would I best go about checking if registered user is still logged in or not? Any ideas would be much appreciated as am out of ideas here.
You're right that the PHP/Ajax calls can cause quite a bit of server load, especially if your Apache/PHP stack needs a lot of memory to bootstrap. Many chat modules in PHP systems, e.g. Drupal, actually offload this responsibility onto a specialized node.js server (the second approach you mentioned) to facilitate scaling.
Another approach you may consider is to use a real-time network such as PubNub to facilitate this user-to-user data transfer. PubNub has a toolkit called Presence which can help with telling who is subscribed or unsubscribed to each channel.
To fit this to your requirements, I imagine that each user will register with the page they are viewing upon landing on it, by issuing this call in your JavaScript:
<script src="https://cdn.pubnub.com/pubnub.min.js"></script>
<script>
var pubnub = PUBNUB({
uuid : '12345-page35' //You can define this for each user
})
pubnub.subscribe({
channel : 'site-wide-chat,page35', //Subscribe to two channels!
message : receive_chat, //Callback function
presence : user_joined //Callback function
})
</script>
When the "owner" logs in the other users viewing the page are notified. You can accomplish that like this:
function user_joined(event) {
if (event.uuid.match(/page35/)) { //You can set your own test here
// .... admin available for chat
}
}
Presence also has a bunch of nifty features such as the ability to get all users subscribed to the current channel:
pubnub.here_now({
channel : 'page35',
callback : function(m){console.log(m)}
});
I hope this helps you build your minimum viable product. Since everything is implemented at the programming language level, you should have a lot of flexibility crafting a customizable chat solution without adding additional complexity or overhead on your server.
I am trying to implement a Facebook-like live notifications system to notify users whenever someone adds them as friend, like their post or posts replies to their comments.
All the database and PHP part is done, but I can't figure out how to implement it like Facebook has.
Whenever someone likes/comments on your post in Facebook the light blue box appears at the bottom left corner of the screen. This happens as soon as someone hits like button or posts comment in Facebook. I would like to know what I should do to implement this.
Using YUI or any JavaScript framework I can query a database table after n seconds to check for notifications. This method is too heavy.
I was wondering if there is any server side mod or scripting can be done so that whenever there is new notification entry in my database table the server will tell that particular client. That way unnecessary request calls from client to server will be avoided completely and system can work efficiently for website with more than 50,000 users online at a time.
How can I achieve this?
You should look into COMET techniques, such as forever frame (tutorial) and long polling. That allows you to have a form of a server->client push communication.
I am really surprised nobody has mentioned PubNub and Pusher
These two (competitors) are building infrastructure which allows for realtime notifications, just like Facebook.
Facebook notification
You basically set a request up, like callng the service that asks your server/db for the notifications of that user. You may do a while loop that retries if theres no notification (maybe Thread.Sleep in between searches). Your js request will timeout, then you can call the function again in timeout. This means long polling afaik
The only way to do it is to have some sort of mechanism (e.g. Javascript) to repeatedly poll the server for updates. Doing server pushes to web browsers isn't possible.