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Posted to users@wicket.apache.org by Engler Adrian <ad...@ecofin.ch> on 2009/12/14 14:52:55 UTC
Buffer not retrieved if RENDER_TO_BUFFER is used with IndexedHybridUrlCodingStrategy and the web server uses URL rewriting (cookies switched off)
Hello,
In a Wicket web application (Wicket 1.4.3) I noticed that feedback
messages were not displayed when cookies were disabled in the browser.
It turned out that this problem had to do with the combination of the
URL coding strategy that was used (IndexedHybridUrlCodingStrategy) and
the render strategy, RenderStrategy.REDIRECT_TO_BUFFER (which is the
default). What actually happens when cookies are switched off is that
the page is rendered to a buffer, a redirect is sent, but then the
server does not recognize that it should use the contents of the buffer
because the URLs do not match, and therefore the page is rendered again
(this time without the feedback messages because they are now already
marked as rendered), the buffer is not used.
If the render strategy is changed to RenderStrategy.REDIRECT_TO_RENDER,
there is no problem without cookies; the problem only exists when the
page is first rendered to a buffer and then this buffer is not used.
The attached minimal application demonstrates this behavior: When
cookies are enabled, you can click the button "Show feedback message" on
the page, and a message "Info message generated <time>" is shown. If
cookies are disabled, no feedback message is shown.
Example from debugging:
In WebRequestCycle.redirectTo(...), the variable redirectURL is assigned
the value home.0;jsessionid=1ie4koskoj2bn; addBufferedResponse is then
called with the value home.0;jsessionid=1ie4koskoj2bn for buffered.
Then, after the redirect, in WicketFilter.doGet(...),
WebApplication.popBufferedResponse is called with the value home.0 for
the relativePath parameter. In that method, the buffered response is not
found (because the real key is home.0;jsessionid=1ie4koskoj2bn).
The problem is that when the buffer is put to the map, a key that
includes the session ID is used, while for retrieval of the buffered
page, a key without the session ID is used.
This problem occurs when IndexedHybridUrlCodingStrategy or the super
class HybridUrlCodingStrategy is used.
If the page is not mounted (and not bookmarkable after the form has been
submitted), there are no problems without cookies because a key without
the jsessionid is used for storing the buffered response in a map. This
has to do with the fact that in WebRequestCycle.redirectTo(...) only the
part of the URL after the "?" is used as a key:
int index = stripped.indexOf("?");
[...]
((WebApplication) application).addBufferedResponse(sessionId,
stripped.substring(index + 1), servletResponse);
If the page is mounted with a HybridUrlCodingStrategy, the value
assigned to the variable stripped is a string without a "?", therefore,
index has the value -1 and a URL with jsessionid is used as a key for
the buffered page.
I think it might be good if someone has a look into this; it might also
be hat in some settings a response is rendered twice (first into the
buffer then for the client because the buffer is not retrieved because
of a URL mismatch) without users noticing anything (as long as feedback
messages are not used).
Thank you!
RE: Buffer not retrieved if RENDER_TO_BUFFER is used with IndexedHybridUrlCodingStrategy and the web server uses URL rewriting (cookies switched off)
Posted by Engler Adrian <ad...@ecofin.ch>.
Thank you for your answer; I have created the JIRA issue
https://issues.apache.org/jira/browse/WICKET-2615
Since the problem only occurs with the default render strategy
RenderStrategy.REDIRECT_TO_BUFFER in combination with certain URL coding
strategies, there are workarounds, such as using
RenderStrategy.REDIRECT_TO_RENDER, therefore I suppose it should be
categorized as Minor.
However, I think this issue points at potential problems with the key
used with RenderStrategy.REDIRECT_TO_BUFFER for storing buffered
responses that might (in combination with certain URL coding strategies)
go beyond the issue observed with URL rewriting in this case - so,
although it is not urgent, it might still be important.
Adrian Engler
-----Original Message-----
From: Martijn Dashorst [mailto:martijn.dashorst@gmail.com]
Sent: Montag, 14. Dezember 2009 15:00
To: users@wicket.apache.org
Subject: Re: Buffer not retrieved if RENDER_TO_BUFFER is used with
IndexedHybridUrlCodingStrategy and the web server uses URL rewriting
(cookies switched off)
Ah... ok. this is a bug, file a JIRA issue please.
Martijn
On Mon, Dec 14, 2009 at 2:59 PM, Martijn Dashorst
<ma...@gmail.com> wrote:
> Use the URL Rewriting features of your container.
>
> Martijn
>
> On Mon, Dec 14, 2009 at 2:52 PM, Engler Adrian
<ad...@ecofin.ch> wrote:
>> Hello,
>>
>> In a Wicket web application (Wicket 1.4.3) I noticed that feedback
>> messages were not displayed when cookies were disabled in the
browser.
>> It turned out that this problem had to do with the combination of the
>> URL coding strategy that was used (IndexedHybridUrlCodingStrategy)
and
>> the render strategy, RenderStrategy.REDIRECT_TO_BUFFER (which is the
>> default). What actually happens when cookies are switched off is that
>> the page is rendered to a buffer, a redirect is sent, but then the
>> server does not recognize that it should use the contents of the
buffer
>> because the URLs do not match, and therefore the page is rendered
again
>> (this time without the feedback messages because they are now already
>> marked as rendered), the buffer is not used.
>>
>> If the render strategy is changed to
RenderStrategy.REDIRECT_TO_RENDER,
>> there is no problem without cookies; the problem only exists when the
>> page is first rendered to a buffer and then this buffer is not used.
>>
>> The attached minimal application demonstrates this behavior: When
>> cookies are enabled, you can click the button "Show feedback message"
on
>> the page, and a message "Info message generated <time>" is shown. If
>> cookies are disabled, no feedback message is shown.
>>
>> Example from debugging:
>> In WebRequestCycle.redirectTo(...), the variable redirectURL is
assigned
>> the value home.0;jsessionid=1ie4koskoj2bn; addBufferedResponse is
then
>> called with the value home.0;jsessionid=1ie4koskoj2bn for buffered.
>> Then, after the redirect, in WicketFilter.doGet(...),
>> WebApplication.popBufferedResponse is called with the value home.0
for
>> the relativePath parameter. In that method, the buffered response is
not
>> found (because the real key is home.0;jsessionid=1ie4koskoj2bn).
>>
>> The problem is that when the buffer is put to the map, a key that
>> includes the session ID is used, while for retrieval of the buffered
>> page, a key without the session ID is used.
>>
>> This problem occurs when IndexedHybridUrlCodingStrategy or the super
>> class HybridUrlCodingStrategy is used.
>>
>> If the page is not mounted (and not bookmarkable after the form has
been
>> submitted), there are no problems without cookies because a key
without
>> the jsessionid is used for storing the buffered response in a map.
This
>> has to do with the fact that in WebRequestCycle.redirectTo(...) only
the
>> part of the URL after the "?" is used as a key:
>>
>> int index = stripped.indexOf("?");
>> [...]
>> ((WebApplication) application).addBufferedResponse(sessionId,
>> stripped.substring(index + 1), servletResponse);
>>
>> If the page is mounted with a HybridUrlCodingStrategy, the value
>> assigned to the variable stripped is a string without a "?",
therefore,
>> index has the value -1 and a URL with jsessionid is used as a key for
>> the buffered page.
>>
>> I think it might be good if someone has a look into this; it might
also
>> be hat in some settings a response is rendered twice (first into the
>> buffer then for the client because the buffer is not retrieved
because
>> of a URL mismatch) without users noticing anything (as long as
feedback
>> messages are not used).
>>
>> Thank you!
>>
>>
>>
>> ---------------------------------------------------------------------
>> To unsubscribe, e-mail: users-unsubscribe@wicket.apache.org
>> For additional commands, e-mail: users-help@wicket.apache.org
>>
>
>
>
> --
> Become a Wicket expert, learn from the best: http://wicketinaction.com
> Apache Wicket 1.4 increases type safety for web applications
> Get it now: http://www.apache.org/dyn/closer.cgi/wicket/1.4.0
>
--
Become a Wicket expert, learn from the best: http://wicketinaction.com
Apache Wicket 1.4 increases type safety for web applications
Get it now: http://www.apache.org/dyn/closer.cgi/wicket/1.4.0
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---------------------------------------------------------------------
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Re: Buffer not retrieved if RENDER_TO_BUFFER is used with
IndexedHybridUrlCodingStrategy and the web server uses URL rewriting (cookies
switched off)
Posted by Martijn Dashorst <ma...@gmail.com>.
Ah... ok. this is a bug, file a JIRA issue please.
Martijn
On Mon, Dec 14, 2009 at 2:59 PM, Martijn Dashorst
<ma...@gmail.com> wrote:
> Use the URL Rewriting features of your container.
>
> Martijn
>
> On Mon, Dec 14, 2009 at 2:52 PM, Engler Adrian <ad...@ecofin.ch> wrote:
>> Hello,
>>
>> In a Wicket web application (Wicket 1.4.3) I noticed that feedback
>> messages were not displayed when cookies were disabled in the browser.
>> It turned out that this problem had to do with the combination of the
>> URL coding strategy that was used (IndexedHybridUrlCodingStrategy) and
>> the render strategy, RenderStrategy.REDIRECT_TO_BUFFER (which is the
>> default). What actually happens when cookies are switched off is that
>> the page is rendered to a buffer, a redirect is sent, but then the
>> server does not recognize that it should use the contents of the buffer
>> because the URLs do not match, and therefore the page is rendered again
>> (this time without the feedback messages because they are now already
>> marked as rendered), the buffer is not used.
>>
>> If the render strategy is changed to RenderStrategy.REDIRECT_TO_RENDER,
>> there is no problem without cookies; the problem only exists when the
>> page is first rendered to a buffer and then this buffer is not used.
>>
>> The attached minimal application demonstrates this behavior: When
>> cookies are enabled, you can click the button "Show feedback message" on
>> the page, and a message "Info message generated <time>" is shown. If
>> cookies are disabled, no feedback message is shown.
>>
>> Example from debugging:
>> In WebRequestCycle.redirectTo(...), the variable redirectURL is assigned
>> the value home.0;jsessionid=1ie4koskoj2bn; addBufferedResponse is then
>> called with the value home.0;jsessionid=1ie4koskoj2bn for buffered.
>> Then, after the redirect, in WicketFilter.doGet(...),
>> WebApplication.popBufferedResponse is called with the value home.0 for
>> the relativePath parameter. In that method, the buffered response is not
>> found (because the real key is home.0;jsessionid=1ie4koskoj2bn).
>>
>> The problem is that when the buffer is put to the map, a key that
>> includes the session ID is used, while for retrieval of the buffered
>> page, a key without the session ID is used.
>>
>> This problem occurs when IndexedHybridUrlCodingStrategy or the super
>> class HybridUrlCodingStrategy is used.
>>
>> If the page is not mounted (and not bookmarkable after the form has been
>> submitted), there are no problems without cookies because a key without
>> the jsessionid is used for storing the buffered response in a map. This
>> has to do with the fact that in WebRequestCycle.redirectTo(...) only the
>> part of the URL after the "?" is used as a key:
>>
>> int index = stripped.indexOf("?");
>> [...]
>> ((WebApplication) application).addBufferedResponse(sessionId,
>> stripped.substring(index + 1), servletResponse);
>>
>> If the page is mounted with a HybridUrlCodingStrategy, the value
>> assigned to the variable stripped is a string without a "?", therefore,
>> index has the value -1 and a URL with jsessionid is used as a key for
>> the buffered page.
>>
>> I think it might be good if someone has a look into this; it might also
>> be hat in some settings a response is rendered twice (first into the
>> buffer then for the client because the buffer is not retrieved because
>> of a URL mismatch) without users noticing anything (as long as feedback
>> messages are not used).
>>
>> Thank you!
>>
>>
>>
>> ---------------------------------------------------------------------
>> To unsubscribe, e-mail: users-unsubscribe@wicket.apache.org
>> For additional commands, e-mail: users-help@wicket.apache.org
>>
>
>
>
> --
> Become a Wicket expert, learn from the best: http://wicketinaction.com
> Apache Wicket 1.4 increases type safety for web applications
> Get it now: http://www.apache.org/dyn/closer.cgi/wicket/1.4.0
>
--
Become a Wicket expert, learn from the best: http://wicketinaction.com
Apache Wicket 1.4 increases type safety for web applications
Get it now: http://www.apache.org/dyn/closer.cgi/wicket/1.4.0
---------------------------------------------------------------------
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Re: Buffer not retrieved if RENDER_TO_BUFFER is used with
IndexedHybridUrlCodingStrategy and the web server uses URL rewriting (cookies
switched off)
Posted by Martijn Dashorst <ma...@gmail.com>.
Use the URL Rewriting features of your container.
Martijn
On Mon, Dec 14, 2009 at 2:52 PM, Engler Adrian <ad...@ecofin.ch> wrote:
> Hello,
>
> In a Wicket web application (Wicket 1.4.3) I noticed that feedback
> messages were not displayed when cookies were disabled in the browser.
> It turned out that this problem had to do with the combination of the
> URL coding strategy that was used (IndexedHybridUrlCodingStrategy) and
> the render strategy, RenderStrategy.REDIRECT_TO_BUFFER (which is the
> default). What actually happens when cookies are switched off is that
> the page is rendered to a buffer, a redirect is sent, but then the
> server does not recognize that it should use the contents of the buffer
> because the URLs do not match, and therefore the page is rendered again
> (this time without the feedback messages because they are now already
> marked as rendered), the buffer is not used.
>
> If the render strategy is changed to RenderStrategy.REDIRECT_TO_RENDER,
> there is no problem without cookies; the problem only exists when the
> page is first rendered to a buffer and then this buffer is not used.
>
> The attached minimal application demonstrates this behavior: When
> cookies are enabled, you can click the button "Show feedback message" on
> the page, and a message "Info message generated <time>" is shown. If
> cookies are disabled, no feedback message is shown.
>
> Example from debugging:
> In WebRequestCycle.redirectTo(...), the variable redirectURL is assigned
> the value home.0;jsessionid=1ie4koskoj2bn; addBufferedResponse is then
> called with the value home.0;jsessionid=1ie4koskoj2bn for buffered.
> Then, after the redirect, in WicketFilter.doGet(...),
> WebApplication.popBufferedResponse is called with the value home.0 for
> the relativePath parameter. In that method, the buffered response is not
> found (because the real key is home.0;jsessionid=1ie4koskoj2bn).
>
> The problem is that when the buffer is put to the map, a key that
> includes the session ID is used, while for retrieval of the buffered
> page, a key without the session ID is used.
>
> This problem occurs when IndexedHybridUrlCodingStrategy or the super
> class HybridUrlCodingStrategy is used.
>
> If the page is not mounted (and not bookmarkable after the form has been
> submitted), there are no problems without cookies because a key without
> the jsessionid is used for storing the buffered response in a map. This
> has to do with the fact that in WebRequestCycle.redirectTo(...) only the
> part of the URL after the "?" is used as a key:
>
> int index = stripped.indexOf("?");
> [...]
> ((WebApplication) application).addBufferedResponse(sessionId,
> stripped.substring(index + 1), servletResponse);
>
> If the page is mounted with a HybridUrlCodingStrategy, the value
> assigned to the variable stripped is a string without a "?", therefore,
> index has the value -1 and a URL with jsessionid is used as a key for
> the buffered page.
>
> I think it might be good if someone has a look into this; it might also
> be hat in some settings a response is rendered twice (first into the
> buffer then for the client because the buffer is not retrieved because
> of a URL mismatch) without users noticing anything (as long as feedback
> messages are not used).
>
> Thank you!
>
>
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscribe@wicket.apache.org
> For additional commands, e-mail: users-help@wicket.apache.org
>
--
Become a Wicket expert, learn from the best: http://wicketinaction.com
Apache Wicket 1.4 increases type safety for web applications
Get it now: http://www.apache.org/dyn/closer.cgi/wicket/1.4.0
---------------------------------------------------------------------
To unsubscribe, e-mail: users-unsubscribe@wicket.apache.org
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