Where to find error output for syntax errors in graphing files

In the process of writing plugins, I sometimes make syntax errors. For errors in …/plugins/…/agent_based I can easily see them either in the cmk output or in a crash report.

However, sometimes I introduce errors in a metric or graph declaration in …/plugins/…/graphing. In such a case the whole file is simply not loaded at all. Unfortunately I cannot find if those types of parser errors are logged anywhere? They don’t seem to appear in ~/var/log/web.log, nor in ~/var/log/apache/error_log.

A short example what I’m talking about:

graph_linet_btrfs_health_bth_system_size = graphs.Graph(
    title=Title("block groups for SYSTEM size and used space"),

This was just part of a much larger file, and I just overlooked that one pesky syntax error time & time again… parser errors would definitely have helped.


Inside your dev environment this was not shown as error?
If i paste your code, i get immediately an error message.

I’m usually editing with Emacs via TRAMP (meaning… Emacs running on my workstation, with the files being located on a CheckMK server, automatically transferring via ssh to/from Emacs). With that setup there are no automatic syntax checks, unfortunately. I’ll look into getting it running remotely.

Still, having parser errors output to somewhere would really be helpful. Errors in ruleset definitions show up in web.log, at least.