I got a page in my App where users can chat. Now I want to display the number of Users that are currently viewing the chatpage.
Is there a way to do that?
I thought of an action, that gets called everytime the site gets loaded from a user and increases the value of a variable and decreases it when the user leaves.
Things to take into consideration:
reloads
multiple browserwindows
You can use the impressionist gem, it gives you a lot of nice stats including what you're looking for. Good luck!
Related
I have an rails application with a huge database (hundreds of gigabytes) that has a lot of different options what to do with the data. In some cases, like changing data, this can be done in a background task I do with Sidekiq. But in other cases, like viewing data with a lot of rows and columns or complex SQL queries, the process of getting the data takes quite long.
What I want to do, is show the user that something is happening when he clicks a link. Like the progress bar many browsers have, but more obvious, so even users not used to working with browsers should see that something is happening and loading.
The question is how to do this. I already tried different options with AJAX and jQuery but most of the times I can only do this for certain actions, but basically I want to do it for the whole application. So every time the user sends a request to load a new page, I want to immediately show him, that something is happening.
The closest I came was a Javascript, that was always triggered. The problem was that it literally happened every time and forced to reload the page. This means when I toggled an element it showed the progress bar and then reloaded the page.
In essence, what I'm looking for:
My application runs on Ruby and Rails 4 and every time a new page is loaded I want the user to show that his request is being processed, so even if the request takes a couple of seconds, the user won't get nervous because he knows that something is happening.
I would really appreciate any help for finding a solution, because I can't seem to find any...
You should use a javascript animation to show to the user that something is happening.
For example : http://ricostacruz.com/nprogress/
Apologies in advance as I'm sure this topic has no doubt been asked before but I couldn't find any post that answers my specific query.
Bearing in mind that I'm new to MVC this is where I have got to. I've got a project developed under VS 2010 using the MVC 3 framework. I've got a search page which consists of 6 fields and a nested model which itself holds around 3 fields.
I can successfully post all this data back to itself and the data is successfully passed as a model and back agian so the fields keep the data which the user has supplied.
Before I move on to actually using this search criteria on another view a thought hit me. I want to keep this search criteria, and possibly even the search results in memory for the duration of the users session.
The reasoning behind this is simply to save my users time by:
a) negating the need to keep re-inputting their search criteria regardless of how they enter or leave the search page
b) speed up the user experience by presenting the search results more quickly
The later isn't as important as the first requirement.
I've done some google searches and indeed had a look through this site on similar topics. From what I've read using sessions (which I would typically use if developing a PHP site) is a no no. From the reasons I've read as to why you shouldn't use sessions seem valid and I'm happy to go along with it.
But now I'm left in a place where I'm scratching my head wondering to myself what exactly is best practice to achieve this simple goal that could be applied to similar situations later down the line in the project.
I also looked at the OutputCache method and that didn't behave as I expected it to. In a test I set the timeout for 30 seconds. After submitting a search I clicked the link to my search page to see if the fields would auto-populate, they didn't. But then clicking the search button the values in the cache were retrieved. I thought I was making progress but when I tried to submit a new value the old value from the cache came back i.e. I couldn't actually change my search criteria with the cache enforced. So I've discounted this as an avenue to explore.
The last option seems to suggest the use of cookies as the most likely candidate, but rightly or wrongly I feel this isn't the best solution. I would have thought the MVC 3 design pattern would have an easier and recommended method of persisting values. I'm sure there is but I've just not discovered it yet.
I have started to use JQuery and again this has been mentioned but I'm not sure this is right direction to take either.
So in summary my question really comes down to what is considered by the wider community as best practice for persisting data in my situation. Effiency, scalability and resiliancy is paramount as I'll have a large global user base that will end up using this web app.
Thanks in advance!
Pete
I'd just use cookies. They're simple to use, you can persist them for as long as you want or have them expire when the users closes their browser, and it doesn't sound like you are storing anything sensitive in them.
I know Stackoverflow doesn't want discussions, so I will try to ask an answerable question here: basically, I am building a admin area with naught but a table that has a few columns like project name, due date, sort of normal stuff.
But is there a technique that allows non-polling updating of when attribute(s) changes in the server, it gets reflected on the user's loaded page?
The table's data comes from a JSON call to the server, and it gets rendered with some javascript onto the table. Real simple stuff. If you must ask for an example. sure, just a table of first and last names.
Homer | Simpson
Lisa | Simpson
Bart | Simpson
This page is opened on many of our users, then if I change Homer to Remoh, without having the user refresh the page, I want the updated name be, well, updated on the table display.
Does Websocket or the pub/sub pattern have something to do with this?
Thank you!
You're looking for a websocket or pub/sub system, exactly as you think.
If this is a Rails application and you're using AJAX stuff -- and it sounds like both things are true -- then your best bet is Juggernaut, which makes the entire process seamless and easy.
It's relatively painless to use, and the author has a great sample app called Holla that almost solves your problem by itself.
If I understand your question correctly, you want all changes to the model data to reflect on the admin panel without the need for refreshing the page. That sounds like a job for some simple. AJAX.
In your js.erb file for your admin page, poll for changes every x seconds and if the results of that query are different than whats currently being displayed. Update the table's data.
Of course this is limited to how often you are calling the function with setTimeOut, but the plus side is that you can tweak that to be just what you like.
If you'd like something more 'out of the box' and more instantaneous. I'd go with #Veraticus's suggestions.
What I would like to do is have my admin user be able to see - in real time (via some AJAX/jQuery niceness) - what my user's are doing.
How do I go about doing that ?
I assume it has something to do with session activity - and I have started saving the session to the db, rather than the cookie.
But generally speaking, how do I take that info and parse it in real time ?
I looked at my session table and aside from the ids (id and session_id), I see a 'data' field. That data field stores a hash - which I can't make any sense of (looks like an md5 hash).
How would I use that to see that User A just clicked on Link B, and right after that User B clicked on link A, etc. ?
Is there a gem - aside from rackamole - that might be able to help me?
You might want to check out Mixpanel. They are easy to setup and have some of what you are asking for.
The session data only contains the values stored in the session[]-hash from the user. It doesn't store which action/controller was called, so you don't know which "link was clicked".
Get the activity of your users:
Besides rackamole you have two options IMHO.
Use a before_filter in your ApplicationController to store the relevant info you are interested in. (Name of controller, action or URI, additional parameters and id of the logged in user for example).
Use an AJAX-call at the bottom of each page which posts back the info you are interested in (URI, id of logged in user, etc.) to your server. This allows faster response times from the server, as the info is stored after the page has already been delivered. Plus, you don't have to use a Rails-request to store it. The AJAX-request could also be calling a simple PHP-script writing the data to disk. This is much faster.
Storing this activity:
Store this data/info either in the database or in a logfile. The database will give your more flexibility like showing all actions from one user, or all visitors for one page, etc. The logfile solution will give you better performance.
Realtime vs. Oldschool:
As for pulling out your collected data in realtime, you have to build your own solution. To do this elegantly (without querying your server once a second to look if new data has arrived) you'll need another server process. Search for AJAX Push for more info.
Depending on your application I'd ask myself if realtime notifications for this are really necessary (because of all the hassles of setting this up).
To monitor the activity on your site, it should be enough to have a page listing the latest actions and manually refresh it (or refresh it automatically every ten seconds).
Maybe you can test https://github.com/raid5/acts_as_scribe#readme
It works with Rails 3 too.
I have a rails application on a shared server that also has a decently sized database, which is still growing, behind it. The application takes a long time to start/load the homepage, about 20-30 seconds for me, although some people report waiting up to several minutes.
Is there a way to flash a notice that informs people that the database may take several minutes to load while they are waiting?
It's hard to say based on your question, since we don't know exactly what your home page is showing or how it's displaying it, but assuming you are referring to an AJAX (based on the tag) call that is retrieving something from the database to be displayed on your homepage, there are a few things you can try:
Paginate the items. Is whatever you're loading a long list of items? If so, only retrieve a few at once, and let the user decide if they want to see more.
Load the rest of the page (header, footer, navigation bar, etc), and then place a loading gif spinner in the area where the content is to be loaded. If you use a javascript library like jQuery this is pretty trivial, and there are a ton of tutorials out there for it. Here is a good site for free loading indicators: http://ajaxload.info/. What you'll want to do is make the AJAX call and use your javascript library to set the loading image. Then, in the success callback for your ajax call, hide the spinner and show the content.
Load one item at a time. Make a separate ajax call for each item you're going to load, so that the user sees them coming in. This will probably end up taking longer overall (you're hitting the database more often), but the visual may be a nice psychological hack.
Look at how your database queries are set up. Are you getting everything you need in one find? That's the best way to do it, as every time you have to make another trip to the database you're increasing the wait time.
Other than that the best thing you can do is get better hardware if possible, maybe look into a VPS like linode.com.