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prathamesh-sonpatki
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jeremy
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| @@ -86,12 +101,16 @@ def etag(&etagger) | ||
| # | ||
| # before_action { fresh_when @article, template: 'widgets/show' } | ||
| # | ||
| - def fresh_when(object = nil, etag: object, last_modified: nil, public: false, template: nil) | ||
| + def fresh_when(object = nil, etag: nil, weak_etag: nil, strong_etag: nil, last_modified: nil, public: false, template: nil) | ||
| + weak_etag ||= etag || object unless strong_etag |
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claudiob
Mar 2, 2017
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Hello @jeremy ! I have a question about this change (if you remember… it's almost one year old).
Before this PR, I was able to use fresh_when to cache a page based solely on last_modified, and completely ignoring the body.
For instance, I could have an action like this:
def index
@sections = Section.all
fresh_when @sections, etag: nil
endwhich would render the page if any Section had been updated, or respond with 304 otherwise.
After this PR, I cannot find a way to not set an etag.
Even if I pass etag: nil or etag: false, this line:
weak_etag ||= etag || object unless strong_etagends up using object as the value of etag.
I understand the good intention of this PR: in principle, if your response has changed (and therefore Etag), you want to expire the cache. However, in my case, using last_modified is enough. If last_modified didn't change, then I want to serve the cached version without checking the Etag as well.
Am I correct in saying that this approach cannot be taken anymore after this PR?
claudiob
Mar 2, 2017
Member
Hello @jeremy ! I have a question about this change (if you remember… it's almost one year old).
Before this PR, I was able to use fresh_when to cache a page based solely on last_modified, and completely ignoring the body.
For instance, I could have an action like this:
def index
@sections = Section.all
fresh_when @sections, etag: nil
endwhich would render the page if any Section had been updated, or respond with 304 otherwise.
After this PR, I cannot find a way to not set an etag.
Even if I pass etag: nil or etag: false, this line:
weak_etag ||= etag || object unless strong_etagends up using object as the value of etag.
I understand the good intention of this PR: in principle, if your response has changed (and therefore Etag), you want to expire the cache. However, in my case, using last_modified is enough. If last_modified didn't change, then I want to serve the cached version without checking the Etag as well.
Am I correct in saying that this approach cannot be taken anymore after this PR?
jeremy commentedApr 1, 2016
Introduce
Response#strong_etag=and#weak_etag=and analogous optionsfor
fresh_whenandstale?.Response#etag=sets a weak ETag.Strong ETags are desirable when you're serving byte-for-byte identical
responses that support Range requests, like PDFs or videos (typically
done by reproxying the response from a backend storage service).
Also desirable when fronted by some CDNs that support strong ETags
only, like Akamai.
No longer strips quotes (
") from ETag values before comparing them.Quotes are significant, part of the ETag. A quoted ETag and an unquoted
one are not the same entity.
Support
If-None-Match: *. Rarely useful for GET requests; meantto provide some optimistic concurrency control for PUT requests.