We have an .NET app. After deployment, we noticed that a number of users had to clear their cache in order for the page to work properly.
I was wondering if an IIS app recycling would do the same thing so the users do not need to clear their local cache.
The server provides caching hints to the client in the response to each resource--many websites have different responses depending on the resource type (static files like .js libraries, css and images, versus dynamic results from .asp pages or API calls). You can use Postman or Fiddler or the developer tools in your browser to view the response headers...and then you can control expiration either in the web.config, the global.asax or your individual code file.
For more information see:
https://learn.microsoft.com/en-us/iis/configuration/system.webserver/staticcontent/clientcache
https://thedeveloperblog.com/expiration#:~:text=Expiration%20is%20key%20to%20caching%20in%20ASP.NET.%20We,performance%2C%20resulting%20in%20pages%20being%20expired%20much%20sooner.
Related
I have a website which sits on a non-public domain and is delivered via a proxy through on a different domain. We're having some trouble with caching of content - this is an Umbraco site and making changes updates the pages if you hit the domain directly, but not through the proxy.
I've been informed that the proxy honours response headers and setting an eTag would fix the issue. Having looked into this I can see that IIS sets the eTag by default, and I can see this is working on static content i.e. .js, .css files like so:
However, if I visit a page on the site, for example /uk/products/product I don't see the eTag header.
Is this expected behaviour, should it only be working with those static content files or can I set this on the page to tell the proxy that it should recache?
The ETag HTTP response header is an identifier for a specific version of a resource. It lets caches be more efficient and save bandwidth, as a web server does not need to resend a full response if the content has not changed. Additionally,etags help prevents simultaneous updates of a resource from overwriting each other ("mid-air collisions").
If the resource at a given URL changes, a new Etag value must be generated.
Static content does not change from request to request. The content that gets returned to the Web browser is always the same. Examples of static content include HTML, JPG, or GIF files.
IIS automatically caches static content (such as HTML pages, images, and style sheets), since these types of content do not change from request to request. IIS also detects changes to the files when you make updates, and IIS flushes the cache as needed.
to enable caching in iis you could use iis output caching feature:
1)open iis manager. select site.
2)select the output caching feature from the middle pane.
3)select edit feature setting from the middle pane.
4)check the enable cache and enable kernel cache box and click ok.
if you want to set the ETag as blank you could also do by adding below code in web.config file:
<httpProtocol>
<customHeaders>
<add name="ETag" value="" />
</customHeaders>
</httpProtocol>
refer this below article for more detail:
Caching
To use or not to use ETag, that is the question.
Configure IIS Output Caching
I've read that IIS after version 7 automatically enables E-tags, however, I ran a Pingdom speed test and the report advised me to enable E-tags. I'm not sure that report is accurate, or the information I read about IIS 7 and newer may not be correct.
I'm new to web development and i want to ask that why some website have the "/"?
for example https://www.roblox.com/home, notice the "/home" what does that called
I have tried to search on google and i can't find the answer
And some website have like "/login.php", "/index.html" it can also be html?
These are URLs (https://en.wikipedia.org/wiki/URL) and they identify the resource you are trying to reach. I would suggest reading more about how web pages works to get a better general overview of things(e.g.: https://developer.mozilla.org/en-US/docs/Learn/Getting_started_with_the_web/How_the_Web_works)
How these resources are actually interpreted depends on the server side implementation:
.php are usually processed by PHP web server
Other static files such as images (*.png , *.jpg, etc), html files, svgs, CSS, js, etc - Are usually located in the local server by the web server (httpd, tomcat, IIS, nodejs, and many many others) and the files as transmitted to the client 'as-is'
When using online tools to build websites, these complexities are usually abstracted away, and in the end URLs will just mean a resource identifier.
[domain]/[section]/[page(.html|.php)|resource(.js|.css)]
domain: the address of the website
section: a way to navigate inside the website itself
page: the user interface that might be rendered server side of client side hold the controls shown to user
resource: files that changes how the content in the pages looks and behaves like
I have no experience with Varnish, so please bear with me.
We have inserted Google Tag Manager into a clients site. The Tag Manager injects Google Analytics tracking code (and nothing else) into the page. The clients technical service provider has now complained that the Tag Manager prevents the Varnish cache from working.
My guess is that this has nothing to do with the tag manager as such but is rather caused by the cookies from Google Analytics - apparently in the default configuration pages with cookies are not cached. However since I'm not very familiar with Varnish I cannot speak with any authority in the matter.
So my question is: is there any reason why Google Tag Manager itself (not any tags inside the tag manager) would invalidate a Varnish cache on each request ? A web search turned up nothing specific regarding Varnish and GTM.
Thank you for your time,
Eike
Google Tag Manager will not interfere with Varnish cache in any way. The reason being is that the requests for Google Tag Manager are sent to google-analytics.com, not your website.
The cookies are then set by google-analytics.com and are only sent between the clients browser and google-analytics.com.
This means that Google Tag Manager does not actually have any affect on your website apart from the initial Javascript being loaded from there.
In fact varnish does not validate any cookie that is created through javascript, only caches the "set-cookie header" of the http request.
The problem you may be having is, if the "DataLayer" is placed in the html code, the values of the variables do not change as they would be in cache.
To solve this problem, we must make another http call (ex. ajax) does not to cache, it returns the variables for DataLayer.
I'm using IIS8 on my Windows 8 development machine. I'm developing an ASP.NET MVC 4 WebAPI-based application, which interfaces with 3rd party servers.
One of these servers (Kaltura content management system) sends a notification which I just can't "catch" with my routing and/or controllers. I'm trying to log the full request's URL on IIS to investigate it's syntax.
I've installed IIS Advanced Logging and configured it to log the all available fields (other than performance counters), but the logs does not contain the URL or the request's contents (a form).
My question is, is it possible to log the full URL in IIS?
There is no default way to log all form fields. Logging everything would make log files go huge very quickly. If there was a way to log everything that would mean logging viewstate and all post fields (what if you’re uploading a 20MB file).
If you want to support something like this you would have to create a custom handler or do it in the website code itself (for example in master page so you don’t have to add logging code to every page).
I was reading in google's documentation their new pagespeed plugin, that they recommend using cookieless domains to improve performance:
Static content, such as images, JS and CSS files, don't need to be accompanied by cookies, as there is no user interaction with these resources. You can decrease request latency by serving static resources from a domain that doesn't serve cookies.
Does anybody know how to do this in IIS?
What the Google article is suggesting is that you serve all your static content from another domain where cookies are not initially set by that serving domain.
Cookies are set in two ways - by session cookies (e.g. by ASP or ASP.NET requests) or explicitly by your application.
These will be posted back TO the server on each subsequent request for the domain that set the cookie (regardless of whether the request is for static or dynamic content) thus increasing the request payload.
What you're doing by having a second domain to serve static content (HTML, CSS, Images etc) is making cookie free requests because no initial cookie would be set in the first place for that domain.
In IIS it's your application, ISAPI Filter or ISAPI extension that will add a cookie. If your IIS server is not intercepting requests for static content (because this is usually handled by the kernel mode http.sys driver) then no cookies will be added to the response. It's only further up the request pipeline that cookies come into play.
So basically there isn't a way to explicitly configure cookie-less domains in IIS.
If you simply put all your static resources into, for instance, static.mysite.com, and if you never set any cookies in that domain, then the browser will never send a cookie when retrieving a resource from your static domain.
That's all Google is saying. There's nothing to configure, just to organize.
AFAIK google analytics sets cookie for all subdomains, so it would be useless if you are using analytics?
I've experienced this also, you'd have to use a different domain altogether to avoid analytics/adsense cookies being set. Using static.yourdomain.com won't cut it.
Here's to hoping Google will change their analytics cookies so that we won't all have to buy new domains to serve cookie-less content.
AFAIK google analytics sets cookie for all subdomains, so it would be useless if you are using analytics?
Here's an example using the Google Analytics asynchronous tracking code, of how to set the domain for tracking:
_gaq.push(['_setAccount', 'UA-XXXXXXX-x'],['_setDomainName', 'www.example.com'],['_trackPageview']);
Here's an example using the previous version of tracking code:
var pageTracker = _gat._getTracker("UA-XXXXXXX-x");
pageTracker._setDomainName("www.example.com");
pageTracker._trackPageview();
and here's what Google has to say about this: Google Analytics & Cookies