RE: Handling ResourceNotFound or other exceptions non-fatally?
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RE: Handling ResourceNotFound or other exceptions non-fatally?
 
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Re: Handling ResourceNotFound or other exceptions non-fatally?
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RE: Handling ResourceNotFound or other exceptions non-fatally?
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In reply to this post by Stephen Bayliss
Hi Alex
Trying to produce an example of this has actually narrowed down the circumstances in which I experienced the problem. The exception I get is org.orbeon.oxf.common.OXFException - No state in context. It only occurs when the exception catcher is catching exceptions from an oxf:pipeline call. Furthermore, if no exception was thrown in the called pipeline everything works fine (ie no secondary exception is thrown). If instead of using a <p:choose> construct, I use xslt to pick up the error, then I get org.orbeon.oxf.common.ValidationException - Current processor should be on top of the stack However, in this case if I http-serialize the results (instead of passing to the data output) and call the pipeline as a model (instead of as a view), then this exception is not seen, and data is successfully serialized (though it appears that the exception is still thrown, looking at the logs). I attach my example files (apart from page flow, see below); they are also pasted below. As pasted below, no exception is thrown, data is returned and displayed. To force an exception, modify the input document produced by the oxf:identity processor in exception-example.xpl, eg change the name of the node <childNode>; which means that the document will no longer validate correctly against the schema specified in the subsequent processor. Then you will see the "No state in context" error. To see the exception thrown if xslt is used to process the exception processor output, comment out the <p:choose> in caller.xpl, and uncomment the oxf:xslt processor. Steve ------------------------------------------------------------------------ --- page-flow.xml (fragment) ========================= <page id="exception-example" path-info="/exception-example" view="/exception-error/caller.xpl"/> ------------------------------------------------------------------------ --- caller.xpl ========================= <!-- caller.xpl --> <p:config xmlns:p="http://www.orbeon.com/oxf/pipeline" xmlns:oxf="http://www.orbeon.com/oxf/processors" > <p:param type="output" name="data"/> <!-- call the pipeline --> <p:processor name="oxf:pipeline"> <p:input name="config" href="exception-example.xpl"/> <p:output name="data" id="catch-me"/> </p:processor> <!-- catch any exceptions --> <p:processor name="oxf:exception-catcher"> <p:input name="data" href="#catch-me"/> <p:output name="data" id="caught"/> </p:processor> <!-- look at root note to determine if there was an exception if there was, return some error text, if not, just pass thru --> <p:choose href="#caught"> <p:when test="/exceptions"> <p:processor name="oxf:identity"> <p:input name="data"> <rootNode> <childNode>There was an error</childNode> </rootNode> </p:input> <p:output name="data" id="output"/> </p:processor> </p:when> <p:otherwise> <p:processor name="oxf:identity"> <p:input name="data" href="#caught"/> <p:output name="data" id="output"/> </p:processor> </p:otherwise> </p:choose> <!-- alternative to above: use xslt instead --> <!-- uncomment this, and comment out the p:choose instead --> <!-- <p:processor name="oxf:xslt"> <p:input name="data" href="#caught"/> <p:input name="config"> <xsl:stylesheet version="2.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns=""> <xsl:template match="/"> <xsl:choose> <xsl:when test="/exceptions"> <rootNode> <childNode>There was an error</childNode> </rootNode> </xsl:when> <xsl:otherwise> <xsl:copy-of select="/"/> </xsl:otherwise> </xsl:choose> </xsl:template> </xsl:stylesheet> </p:input> <p:output name="data" id="output"/> </p:processor> --> <!-- pass the output back --> <p:processor name="oxf:identity"> <p:input name="data" href="#output"/> <p:output name="data" ref="data"/> </p:processor> </p:config> ------------------------------------------------------------------------ --- exception-example.xpl ========================= <!-- exception-example.xpl --> <p:config xmlns:p="http://www.orbeon.com/oxf/pipeline" xmlns:oxf="http://www.orbeon.com/oxf/processors" > <p:param type="output" name="data"/> <!-- dummy input document --> <p:processor name="oxf:identity"> <p:input name="data"> <rootNode> <childNode>sometext</childNode> </rootNode> </p:input> <p:output name="data" id="input-doc"/> </p:processor> <!-- dummy transform, note input is validated --> <p:processor name="oxf:xslt"> <p:input name="data" href="#input-doc" schema-href="/exception-error/schema.rng"/> <p:input name="config"> <xsl:stylesheet version="2.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns=""> <xsl:template match="/"> <xsl:copy-of select="/"/> </xsl:template> </xsl:stylesheet> </p:input> <p:output name="data" ref="data"/> </p:processor> </p:config> ------------------------------------------------------------------------ --- schema.rng ========================= <grammar xmlns="http://relaxng.org/ns/structure/1.0"> <start> <element name="rootNode"> <element name="childNode"><text/></element> </element> </start> </grammar> ------------------------------------------------------------------------ --- -----Original Message----- From: [hidden email] [mailto:[hidden email]] On Behalf Of Alessandro Vernet Sent: 01 December 2005 23:37 To: [hidden email] Subject: Re: [ops-users] Handling ResourceNotFound or other exceptions non-fatally? Stephen, We would need more information to help you on this. What is the other exception you are getting? Alex On 11/29/05, Stephen Bayliss <[hidden email]> wrote: > I had a go at using this, and it's useful. > > However, I can't seem to test the output of the oxf:exception-catcher > with a <p:choose>...<p:when> construct, I get another exception... > > I'd be interested to hear how others have implemented this. > > -----Original Message----- > From: Erik Bruchez [mailto:[hidden email]] On Behalf Of Erik Bruchez > Sent: 01 November 2005 23:34 > To: [hidden email] > Subject: Re: [ops-users] Handling ResourceNotFound or other exceptions > non-fatally? > > Ryan, > > There is currently no documentation about this, because we feel > exception handling in XPL is the way to go. > > You use this processor as shown below: just hook its "data" input to > > output that can cause an exception when reading it, and its "data" > output will either contain the document read, or an exception document > in the format returned by the exception generator (which you can look > > just by producing an exception). > > -Erik > > Ryan Puddephatt wrote: > > Erik, > > Is there any documentation on this exception catcher? How would it > be > > implemented into a pipeline? > > > > Thanks > > Ryan > > > > Erik Bruchez wrote: > > > >> Jeff Jones wrote: > >> > >>> I'm trying to use the XPath doc() function to request a snippet of > >>> XHTML from an external resource (via HTTP) and insert it into an > >>> XHTML page I'm generating with OPS 3.0. I can't guarantee, though, > >>> that that HTTP request will always succeed. When it fails, I don't > >>> want to give up on the page; I just want to ignore the error and > >>> deliver the document without the include. How can I do this with > OPS? > >> > >> > >> > >> Ideally, I think, with exception handling in XPL. Currently, there > > >> none, but there is a possibility that this will be implemented in > > >> future. As a temporary hack, you can use the oxf:exception-catcher > >> processor: > >> > >> <p:processor name="oxf:exception-catcher"> > >> <p:input name="data" href="#the-output-of-the-stylesheet"/> > >> <p:output name="data" id="ouput-or-exception-document"/> > >> </p:processor> > >> > >>> I can write a separate pipeline to make the request if necessary, > > >>> use XInclude if its error handling is more flexible; I'm not > >>> to doc(). My first thought was to test with doc-available(), but > even > >>> if it would work, I see in the Saxon docs that it wasn't implemented > > >>> until 8.4. Do I have any other options? > >> > >> > >> > >> The XInclude processor does not yet implement xi:fallback, but it > >> should. When it does, you will be able to use that as an exception > >> mechanism to retrieve HTTP resources, although you won't have any > >> detail of exactly what went wrong. > >> > >> -Erik > >> > >> > > >> > >> > >> -- > >> You receive this message as a subscriber of the > >> [hidden email] mailing list. > >> To unsubscribe: mailto:[hidden email] > >> For general help: mailto:[hidden email]?subject=help > >> ObjectWeb mailing lists service home page: > http://www.objectweb.org/wws > >> > >> > > > > > > > > > > > > > -- > > You receive this message as a subscriber of the > [hidden email] mailing list. > > To unsubscribe: mailto:[hidden email] > > For general help: mailto:[hidden email]?subject=help > > ObjectWeb mailing lists service home page: > http://www.objectweb.org/wws > > > > > > > > -- > You receive this message as a subscriber of the > To unsubscribe: mailto:[hidden email] > For general help: mailto:[hidden email]?subject=help > ObjectWeb mailing lists service home page: > > > -- Blog (XML, Web apps, Open Source): http://www.orbeon.com/blog/ -- You receive this message as a subscriber of the [hidden email] mailing list. 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exception-error.zip (2K)
Re: Handling ResourceNotFound or other exceptions non-fatally?
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Re: Handling ResourceNotFound or other exceptions non-fatally?
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RE: Handling ResourceNotFound or other exceptions non-fatally?
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