On 9/29/2018 3:08 AM, Ryan Qin wrote:
I’m working on a project which uses solr as search engine. I found I
cannot get the root cause of error from SolrJ.
CloudSolrClient uses LBHttpSolrClient internally. This client has a
tendency to wrap all exceptions in the "No live SolrServers" message.
There is an existing issue for that problem:
https://issues.apache.org/jira/browse/SOLR-7951
That issue is three years old, and sorta fizzled out without really
going anywhere. There hasn't been any activity in Jira for nearly two
years.
The root cause is wrapped very deep, like:
The image that you attached did not make it to the list. We can't see
it. Apache mailing lists remove most attachments. Using a paste
website or a file sharing site is the best option for sharing content.
Even if SOLR-7951 is fixed, root causes will still often be deeply
nested in exceptions, and the level of nesting varies widely. Because
the innermost exception in the nesting may not actually say anything
useful about the root cause, trying to determine a root cause
programmatically is very difficult. It usually takes review by a
person, looking at ALL of the "Caused by" messages closely. Often the
problem may only make sense to someone who's actually familiar with the
code, and the exact version of Solr is required to decipher them. The
goal is to have error messages that ANYONE can understand ... but
reaching that goal can be very difficult.
Thanks,
Shawn
