[chef] Re: Re: Life cycle of a chef run

[Daniel DeLeo < >]

Tim,

One (really hacky, some might even say kludgy) way to accomplish what you want, at least for reporting of failed runs via email, would be to include a Ruby at_exit hook in a recipe.  Note that this is only effective if you run the client via cron or some mechanism where the chef-client program exits--so anything using the interval (-i) option won't work with this hack. Here's some code that demonstrates the various behaviors you can see with at_exit

at_exit do

  p $!.inspect

end

def raise_error

  raise "an uncaught error"

end

def let_script_reach_eof

  # don't need to do anything

end

def raise_and_rescue

  begin

    raise "an error that will be rescued"

  rescue => e

    # don't need to do anything

  end

end

def exit_with_exit

  exit 42

end

In the code above, $! is the last "unrescued" error raised. I didn't have a chance to see what the results are when using this in a chef run, so you'll need to do additional research on your own, but from what I can tell you'll have these cases:

* for a successful run, you'll have $!.kind_of?(SystemExit) #=> true and $!.success? #=> true

* Chef might kill itself due to a configuration problem or something, in this case you'll probably see $!.kind_of?(SystemExit) #=> true and $!.success #=> false

* for a run that dies due to an error being raised in a recipe, you should that error in $!, i.e., $!.kind_of?(SystemExit) #=> false

Hope this helps,

Daniel DeLeo

On Thu, Oct 22, 2009 at 10:27 AM, Nick Ohanian < "> > wrote:

I second this.  I had the same need, and I ended up rolling my own scripts to do this.  Otherwise there is no visibility into what's "really" going on in the deployment.  However, while this is certainly an important part of "managing your servers", it might be outside of the scope of Chef's goals.  Chef is good at "configuring your servers", but is it the intent of Chef to (eventually) provide support for "monitoring your servers"?

-Nick

Tim Uckun wrote:

Is there a way to wrap some code around the chef run?

I have two specific goals.

1. Catch exceptions and email them to me.
2. Send some data to my monitoring service after the run (if nothing
else just the fact that the run took place and went OK but I would
like to include other data from ohai).