42 lines
1.5 KiB
Ruby
42 lines
1.5 KiB
Ruby
module ActionController
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module ConditionalGet
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# Sets the etag, last_modified, or both on the response and renders a
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# "304 Not Modified" response if the request is already fresh.
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#
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# Parameters:
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# * <tt>:etag</tt>
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# * <tt>:last_modified</tt>
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# * <tt>:public</tt> By default the Cache-Control header is private, set this to true if you want your application to be cachable by other devices (proxy caches).
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#
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# Example:
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#
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# def show
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# @article = Article.find(params[:id])
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# fresh_when(:etag => @article, :last_modified => @article.created_at.utc, :public => true)
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# end
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#
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# This will render the show template if the request isn't sending a matching etag or
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# If-Modified-Since header and just a "304 Not Modified" response if there's a match.
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#
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def fresh_when(options)
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options.assert_valid_keys(:etag, :last_modified, :public)
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response.etag = options[:etag] if options[:etag]
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response.last_modified = options[:last_modified] if options[:last_modified]
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if options[:public]
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cache_control = response.headers["Cache-Control"].split(",").map {|k| k.strip }
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cache_control.delete("private")
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cache_control.delete("no-cache")
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cache_control << "public"
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response.headers["Cache-Control"] = cache_control.join(', ')
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end
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if request.fresh?(response)
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head :not_modified
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end
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end
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end
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end |