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<p class="MsoNormal"><font size="2" face="Calibri"><span style="font-size:11.0pt">Hi, I’m revamping
<a href="http://lists.rabbitmq.com/pipermail/rabbitmq-discuss/2011-February/011314.html">
this</a> old thread because I’m trying to solve pretty much the same problem. I need to know whether a queue that I have declared still exists on the server or has for any reason been deleted.
<o:p></o:p></span></font></p>
<p class="MsoNormal"><font size="2" face="Calibri"><span style="font-size:11.0pt">Without relying on the management plugin I think the only way to do that is to declare the queue as passive. At least with the .NET client and apparently the Java client too,
when the queue does not exist, besides throwing an exception, the channel is closed as well. From the spec:<o:p></o:p></span></font></p>
<p class="MsoNormal"><font size="2" face="Calibri"><span style="font-size:11.0pt"><o:p> </o:p></span></font></p>
<p class="MsoNormal"><font size="2" color="#555555" face="Verdana"><span style="font-size:10.0pt;font-family:"Verdana","sans-serif";color:#555555;background:#EEEEEE">If set, the server will reply with Declare-Ok if the queue already exists with the same name,
and raise an error if not. The client can use this to check whether a queue exists without modifying the server state.</span></font><font size="3" face="Times New Roman"><span style="font-size:12.0pt;font-family:"Times New Roman","serif""><o:p></o:p></span></font></p>
<p class="MsoNormal"><font size="2" face="Calibri"><span style="font-size:11.0pt"><o:p> </o:p></span></font></p>
<p class="MsoNormal"><font size="2" face="Calibri"><span style="font-size:11.0pt">There is no mention of channel closure, while the last sentence implies that using the passive bit is indeed a way for a client to check queue existence, so closing the channel
when it doesn’t is a bit unexpected.<o:p></o:p></span></font></p>
<p class="MsoNormal"><font size="2" face="Calibri"><span style="font-size:11.0pt">That said, it’s not a big deal to recreate the channel in such cases, but I’d appreciate your opinion. Any chance this behavior can be changed in the client libraries?<o:p></o:p></span></font></p>
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