I am new to pubsubhubbub. I just tried subscribing to a Google Alerts feed, and found that the callback requests contain multiple instances of the Content-Type header. The POST headers look like this:
Content-Type: application/atom+xml Link: <http://pubsubhubbub.appspot.com/>; rel="hub" X-Appengine-Country: ZZ Content-Type: application/atom+xml Host: xxx Content-Length: 55287 Accept-Encoding: gzip This is explicitly disallowed in RFC 2616 (section 4.2, last paragraph). The problem will not be noticed if the server simply discards the extra Content-type header, but in some circumstances the result is delivery failure. I am using the Apache httpd proxy_ajp module as a frontend to Apache TomEE where a JAX-RS application routes POST requests depending on their content-type. It turns out that proxy_ajp collapses multiple instances of the same HTTP header into a single instance with a comma-separated list of values, which RFC 2616 says is semantically equivalent for those headers that are allowed to have lists as values. So what the application sees is: Content-Type: application/atom+xml, application/atom+xml This value does not match any known content-type, and the request fails. This is obviously a bug in proxy_ajp also, it shouldn't treat Content-Type headers like this. But the primary cause of the problem is the non-conforming nature of the original POSTs, so I am reporting it here first. Thanks in advance for any replies & comments on this. -- --- You received this message because you are subscribed to the Google Groups "Pubsubhubbub" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/groups/opt_out.
