I've been searching for a day or 2 for an answer to this question, but I haven't found one yet. I've got an external application which is modifying a TSV file (adding data) periodically. I'm using the Basic Line Chart example to display the data and it looks really nice:
Now I want the data to update when the TSV file is updated. I want to be able to set an auto-refresh on the data where it pulls from the tsv file and repopulates the graph without refreshing the entire page.
I tried just wrapping up the current code in a function and calling setInterval on that function, but the data remains the same each time (maybe because it's cached?).
Ideally the solution to this would be a function which can be called to Update whenever I'd like (based on a user event, timer, whatever).
Any ideas, links, or suggestions for alternate ways to accomplish the same goal would be much appreciated!
As a bonus question: I understand D3 may not be the right choice for this sort of Psudo-Real-Time data display. Are there other packages which lend themselves to this sort of thing more? The app generating the data is a C# application (in case that ends up mattering).
Edit: As a supplementary explanation, imagine this example but with the data being read from a file: http://mbostock.github.com/d3/tutorial/bar-2.html
If you are executing an Ajax call to fetch the data from the server and you think caching is a problem, you can try busting the cache by setting the cache parameter in jquery's ajaxSetup to false anywhere in your code:
$.ajaxSetup({cache: false});
From the docs:
If set to false, it will force requested pages not to be cached by the
browser. Note: Setting cache to false will only work correctly with HEAD and
GET requests. It works by appending "_={timestamp}" to the GET parameters. The
parameter is not needed for other types of requests, except in IE8 when a
POST is made to a URL that has already been requested by a GET.
Related
I have a listing page for an e-commerce website with various items (item_list.php). This page is generated with a PHP loop and displays each item inside a <li> element. Every item is a link to the same page, called item_details.php .
When clicking on the link i want to run a script that changes a SESSION var to a certain $id (which will be excracted from the <li> itself with .innerHTML function) and then allowing the browser to move into the next page (item_details).
This is needed so i can display the proper information about each item.
I think this is possible with Ajax but I would prefer a solution that uses JS and PHP only.
(P.S.This is for a University project and im still a PHP newbie, i tried searching for an answer for a good while but couldn't find a solution)
No JS or other client-side code can set session values, so you need either an ajax call to php, or some workaround. This is not a complete answer, but something to get you thinking and hopefully going on the project again.
The obvious answer is just include it in the link and then get it in PHP from the $_GET -array, and filter it properly.
item title
If, however, there is some reason this is not a question with an obvious answer:
1.) Closest what you're after can be achieved with a callback and an ajax call. The idea is to have the actual link with a click function, returning false so the link doesn't fire at once, which also calls an ajax post request which finally will use document.location to redirect your browser.
I strongly advice against this, as this will prevent ctrl-clicks causing a flawed user experience.
Check out some code an examples here, which you could modify. You will also need an ajax.php file which will actually set the session value. https://developers.google.com/analytics/devguides/collection/analyticsjs/enhanced-ecommerce#product-click
2.) Now, a perhaps slightly better approach, if you truly need to do this client-side could be to use an click handler which instead of performing an ajax call or setting session directly, would be to use jQuery to set a cookie and then access this data on the item_list.php -page.
See more information and instructions here: https://www.electrictoolbox.com/jquery-cookies/
<script>
$('product_li a).click(function(){
$.cookie("li_click_data", $(this).parent().innerhtml());
return true;
});
</script>
......
<li class="product_li">your product title</li>
And in your target php file you check for the cookie. Remember, that this cookie can be set to anything, so never ever trust user data. Test and filter it in order to make sure your code is not compromised. I don't know what you want to do with this data.
$_COOKIE['li_click_data'];
3.) Finally, as the best approach, you should look at your current code, and see if there is something you can re-engineer. Here's a quick example.
You could do the following in php to save an array of the values in the session on each page load, and then get that value provided you have some kind of id or other usable identifier for your items:
// for list_items.php
foreach($item as $i) {
// Do what you normally do, but also set an array in the session.
// Presuming you have an id or some other means (here as item_id), to identify
// an item, then you can also access this array on the item_details -page.
$_SESSION['mystic_item_data_array'][$i['item_id]] = $i['thedata'];
}
// For item_details.php
$item_id = // whatever means you use to identify items, get that id.
$data_you_need = $_SESSION['mystic_item_data_array'][$item_id];
Finally.
All above ways are usable for small data like previous page, filters, keys and similar.
Basically, 1 and 2 (client-side) should only be used, if the data is actually generated client-side. If you have it in PHP already, then process it in php as well.
If your intention is to store actual html, then just regenerate that again on the other page and use one of the above ways to store the small data in case you need that.
I hope this gets you going and at least thinking of how to solve your project. Good luck!
Is there another way to view the profiling results of MiniProfiler (I'm specifically interested in EF5 version)?
Every tutorial that I've seen uses MiniProfiler.RenderIncludes(); but since my MVC app mostly returns JSON, that is not an option for me.
Is there a way to write results to file or something like that?
You can read and write results to just about anywhere by changing the MiniProfiler.Settings.Storage to a different IStorage implementation from the default (which stores to http cache). If you wanted to, this could store to and read from a file pretty easily (you would have to write your own custom implementation for that).
The files served by RenderIncludes are the html templates for displaying the results and the script to retrieve the results from the server and render them on the client (all found here). But you are by no means obliged to use this mechanism. If you want to write your own logic for retrieving and displaying results, you should base this off of the logic found in MiniProfilerHandler.GetSingleProfilerResult. This function roughly performs the following (putting in the siginificant steps for your purposes):
Gets Id of next results to retrieve (through MiniProfiler.Settings.Storage.List())
Retrieves the actual results (MiniProfiler.Settings.Storage.Load(id))
Marks the results as viewed so that they wont be retrieved again (MiniProfiler.Settings.Storage.SetViewed(user, id))
Converts these to ResultsJson and returns it
With access to MiniProfiler.Settings.Storage, you should be able to retrieve, serve and consume the profile results in any way that you want. And if you are interested in using the RenderIncludes engine but want to mess around with the html/js being served, you can provide your own custom ui templates that will replace the default behavior.
I'll start off by mentioning I'm a dojo noob. That said,
I'm having trouble reading data from a itemfilereadstore. When my page is loaded, I perform a .fetch() on a itemfilereadstore. The ajax call retrieves some data from the server and my onComplete handler is executed. My problem is after this store is populated (and after my onComplete handler is executed), I don't see a way to read its contents (enumerate its items) again without hitting the server.
How can I fetch() against this existing datastore without it trying to hit my webserver again? Surely I can look up information that already exists in this object somehow? The dojo documentation doesn't seem to have any obvious answers, what am I missing?
I believe what you're looking for is itemfilereadstore.query. If all you need is to get all the elements, just a plain old query should do the trick. If you need to filter, then you'll have to read up on the query syntax : http://dojotoolkit.org/reference-guide/dojo/data/ItemFileReadStore.html#query-syntax
Web programmer here - using AJAX (HTML, CSS, JavaScript, AJAX, PHP, MySQL), but for some reason Internet Explorer is acting up (surprise surprise).
AJAX is updating query results on the HTML page, via a PHP script that queries a MySQL Database.
Everything is working fine, except when I use Internet Explorer 8.0 .
There are several php scripts, which allow for the data to be ordered according to certain criteria, and for testing purposes I have attached the mktime field (current time, in the format HH:MM:SS) to the beginning of the results for each query.
When I use IE, these times appear to remain constant, whereas with ALL other browsers these times are correct and display the current time.
I think the issue has something to do with caching or something along those lines anyway.
Any thoughts or suggestions welcome...
Here is an article on the caching issue.
If your request is a GET change it to a POST, this will prevent the results being cached.
GET requests are cached in IE; switch it to a POST request and it won't be cached anymore.
Instead of switching to POST, which can be ugly if you're not really using it to update or create content, you should append a random number to the query string, as in http://domain.com/ajax/some-request?r=123456. If this number is unique for every request you won't have caching problems.
What I have done is, I have kept the "GET" and added new dummy query parameter to the querystring as follows,
./BaseServlet?sname=3d_motor&calcdir=20110514&dummyParam=datetime
I set dummyParam a value of date object in the javascript so that every time the url is generated browser will treat it as a new url and fetch new (fresh) results.
var d = new Date();
url = url + '&dummyParam='+d.valueOf();
So instead of generating some random numbers this is easy way!
Renting houses can be nasty so I need to automate it. Please, have a look at here. If you make a mistake, all of your changes are gone. I tried to insert the values in the url like:
https://www.hoas.fi/web/hak_inet.nsf/WebHakemus?OpenForm&02.07?PersonFirstName=Alex?PersonLastName=Smith
but it does not work. What is the problem?
Firstly, your query string is incorrect. It should be:
https://www.hoas.fi/web/hak_inet.nsf/WebHakemus?OpenForm&02.07&PersonFirstName=Alex&PersonLastName=Smith
Secondly, in order to pre-populate the page with the results of the query string, the developer of the page would have had to added logic to extract the query string values and pre-populate the page with those values. In this case, it does not appear that they have done that.
You could try saving the page locally as HTML. Then you could modify the HTML to include your default values. You would also need to update any relative paths to point to the server as a full URL. Then you could open the page on your machine and hopefully post to the server. This assumes that they are not injecting any session or other temporary information in the page that they validate.