Image proxy caching problem

[LoyceV]

This image currently shows 95.79 USD (updated hourly), but when I embed it, I see (at the time of writing: 95.37 USD. A hard refresh or even private window doesn't change this, which makes me think it's cached by the forum's image proxy.

I expected this would still apply:

There is no caching on the bitcointalk.org side. The image is always passed directly from the source server to the user.

@theymos: did something change?

Any Expires or Cache-Control headers sent by the origin server are passed through as well, so caching might be done by the client.

This is the next problem I had, but I think I've solved this on my end. I've added this to my .htaccess (source):

Code:

<filesMatch "\.(gif|png|jpg)$">
  FileETag None
  <ifModule mod_headers.c>
     Header unset ETag
     Header set Cache-Control "max-age=0, no-cache, no-store, must-revalidate"
     Header set Pragma "no-cache"
     Header set Expires "Wed, 11 Jan 1984 05:00:00 GMT"
  </ifModule>
</filesMatch>

[theymos]

Since that DDoS a while ago, the imageproxy is now going through Cloudflare, which will do server-side caching if allowed by the final origin's headers, and client Cache-Control headers are (I think) always ignored now. (I haven't decided yet whether having the imageproxy behind Cloudflare is permanent.)

That pricing image doesn't send any cache-related headers at all, aside from Last-Modified. If that .htaccess file is intended for that image, then it's not working. One major issue in this case is that:
 1. The image doesn't send an Expires header.
 2. If an image doesn't have an Expires header, then the imageproxy sets an Expires 1 day into the future. *
 3. Cloudflare then server-side-caches this for 1 day based on the Expires header, and there's no way for the client to bypass Cloudflare's cache.

* I just now changed the default Expires timeout to 10 minutes instead of 1 day, at least as long as the imageproxy is behind Cloudflare. But for live content like this, it'd be better if the origin sent headers disabling caching entirely.

[LoyceV]

I just now changed the default Expires timeout to 10 minutes instead of 1 day, at least as long as the imageproxy is behind Cloudflare.

Thanks, for now, it works again.

But for live content like this, it'd be better if the origin sent headers disabling caching entirely.

I'll look into how to do this (starting by posting here).

[joker_josue]

This image currently shows 95.79 USD (updated hourly), but when I embed it, I see (at the time of writing: 95.37 USD. A hard refresh or even private window doesn't change this, which makes me think it's cached by the forum's image proxy.

Just an observation. When trying to access the image directly in the browser, an error occurs and it is not possible.
Is it because the browser automatically assumes https, and the image is only in http?



_{I gave another tip in the other topic.}

[LoyceV]

When trying to access the image directly in the browser, an error occurs and it is not possible.
Is it because the browser automatically assumes https, and the image is only in http?

I blame modern browsers. When I click http://proxyimages.bitcoindata.science/, Firefox tries to open https, which doesn't work. But it works in a private window. On the same server, http://addresses.loyce.club/ works normally in Firefox.

The reason I'm not using https is because it's annoying.... Even when I set it up for automated updates, I've had it fail several times in the past. The data isn't that important, so I don't mind the unencrypted connection.

[joker_josue]

When trying to access the image directly in the browser, an error occurs and it is not possible.
Is it because the browser automatically assumes https, and the image is only in http?

I blame modern browsers. When I click http://proxyimages.bitcoindata.science/, Firefox tries to open https, which doesn't work. But it works in a private window. On the same server, http://addresses.loyce.club/ works normally in Firefox.

The reason I'm not using https is because it's annoying.... Even when I set it up for automated updates, I've had it fail several times in the past. The data isn't that important, so I don't mind the unencrypted connection.

I understand perfectly.

They started with these theories that this obligation is safer for everyone. But in the end it made things easier for crooks to make fake websites.