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Questions tagged [etag]

ETag is an HTTP Entity Tag. Use this tag if you have a question about HTTP requests using ETag, If-Match or If-None-Match headers, or the generation and comparison of ETag values.

An ETag is an opaque identifier assigned by a web server to a specific version of a resource found at a URL. If the resource content at that URL ever changes, a new and different ETag is assigned. Used in this manner ETags are similar to fingerprints, and they can be quickly compared to determine if two versions of a resource are the same or not.

http://en.wikipedia.org/wiki/HTTP_ETag

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chrome browser not sending 'If-None-Match' for xhr

I'm using an angular service to GET a resource via a rest api. The server sets the ETag header to some value and it also sets Cache-Control: no-cache in it's response. This works as expected using Firefox, but when I access the same app using…
HK_
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What is the purpose of (Apache) putting inode into an ETag?

There are plenty of articles on the web detailing why you might not want to use Apache's default inode-mtime-size format for ETags. But I have yet to read anything on what might have motivated the inclusion of inode for Apache in the first place. On…
hatfinch
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Using ETag / Last-Modified decorators with Django's class-based generic views

I've recently migrated all views in one of my Django projects to the new class-based ones. For classic function-based Django views there's a handy decorator django.views.decorators.http.condition that can be used to bypass the whole view processing…
jmagnusson
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Why is ETag required to be enclosed in double quotes?

As per the RFC and MDN docs, ETag value is required to be enclosed in double quotes "". When I make a request using CURL with the Accept-Encoding header as gzip, deflate, br, I do not receive the ETag in the response headers if ETag is not…
ankurnarkhede
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Set ETag for FileResult - MVC 3

MVC 3 RTM. I have an action that returns a file (image/jpeg). I am trying to set the ETag for a file with no success (the etag doesn't come through on header). I have tried both Response.Cache.SetETag and Response.AppenderHeader. If I add my own…
B Z
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How to cache okHTTP response from Web server?

I want to know how can okHTTP response from Web server (which returns json data) be cached? I want my app to download all the data needed for RecycleView and cache it once the user runs the app first time - and avoid re-downloading and parsing all…
unipin
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Cloudflare not forwarding ETag header?

I have a site (e.g. http://example.com) that uses Cloudflare. Nothing special, no weird page rules, no weird settings, free plan. When I go to http://example.com, I get this response for the GET http://example.com request: Cache-Control:no-cache,…
Victor Zhou
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How do I use Etags for Youtube v3 Data API?

I am building an extension and it makes a lot of requests. The feature I'm working on is to display the total length of time it would take to watch a playlist. Given a playlist of size 1000, I have to make 40 requests just to find this information…
Ignat
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Does Parse.com Cloud Code Have etag support?

Does Parse.com support the use of etags and if-none-match for Conditional GETs? I'm working with a third party API that requires this as a must, to limit API calls to their server. Im using Cloud Code as my backend sending data to a Cordova/ionic…
garrettmac
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Is it possible to get Semantic (emacs) to visit all files automatically?

From what I can tell from the docs, semantic works by slowly building up an idea of what's in your project by analysing each file (and possibly its neighbours) as you visit them. This is too slow. I'd like to just have it visit all the files in my…
RealityMonster
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How do i use Cache Control and ETag to set http headers

I want to use Cache Control and ETag in my joomla website as suggested by google. But have no idea how to do that. I googled it a lot but could not find any worty example. Can anybody tell me how to do that..?? For Cache Control i have found this…
Gaurav Manral
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How to test rails ETag caching?

Is it possible to cover my controller, that is highly depeinding on Etags with unit tests? Here's what i'm trying to do: in case if page is not stale (meaning that it's fresh), i'm adding some header to response. When i'm trying to test it all…
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How can Javascript view the ETAG value of a HTTP response? Can ETAG be included in a request?

Is it possible for javascript to read the ETAG value of a HTTP response? Are there any issues in writing out an ETAG value in a HTTP Request to the server?
makerofthings7
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Is it possible to make conditional inserts with Azure Table Storage

Is it possible to make a conditional insert with the Windows Azure Table Storage Service? Basically, what I'd like to do is to insert a new row/entity into a partition of the Table Storage Service if and only if nothing changed in that partition…
Mark Seemann
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Where does the W/ in an etag appear from?

I am confused by how the W/ appears in the etag when I have not added it. I am using Node.js http server module and have a Nginx as reverse proxy. I am getting the browser see the Etag generated by the Node.js server but with a W/ tagged to it. Can…
Sunny
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