On Fri, Apr 17, 2009 at 10:48 AM, Chris Webb <chris.webb@elastichosts.com>wrote:
Sam Johnston <samj@samj.net> writes:
You've completely missed the point again. (Perhaps understandably, since you're not in the target audience for this format.)
Don't be so sure - I started life as a sysadmin (like many of us here I guess) :)
while read K V; do FOO; done
Granted that's trivial, but it rapidly gets more interesting when you have multiple resources. As I said before though "*perhaps it's worth it just for the (common) case of dealing with a single object*". I take it you're saying that it is... YAML's another interesting format, and as of 1.2 it's a perfect superset of JSON <http://en.wikipedia.org/wiki/JSON#YAML> (that is, every JSON file is also a YAML file), but it also fails the "one-liner parseability test" miserably.
is something you can type in a shell one-liner, which is the most interesting 'use case' (sorry, horrible jargon!) for shell people. This complex hack is not, and I note that you had to google for it rather than writing it off the top of your head, which should have been enough to make the point clear. (Incidentally, it doesn't get INI quoting right. Doing it correctly and allowing for backslash escapes is somewhat harder.)
Whitespace separated KEY VALUE is better-defined than INI[1], can be parsed by shell read, by C strtok() or strsep(), and is generally pleasant to work with in languages without sophisticated string handling or data structures. Here's your sample translated to that format:
id decca5a5-8952-4004-9793-cdbbf05c3c63 category server title Debian GNU/Linux 5.0 Virtual Appliance summary Base installation of Debian GNU/Linux 5.0 content.cpu 2 content.memory 4Gb link.disk[0].id 4696b561-a253-42b4-bd27-7aa4950e0a60 link.disk[0].dev sda link.network[0].id 45a73b80-c957-4ae1-97c6-b70652eba1d1 link.network[0].dev eth0 mc.state RUNNING br.meter.rate 0.10 br.meter.currency USD br.meter.unit hours br.meter.total 35.27 pm.monitor.cpu 75.2 pm.monitor.mem 1059374258 mc.ops.start http://example.com/decca5a5-8952-4004-9793-cdbbf05c3c63/ops/start mc.ops.stop http://example.com/decca5a5-8952-4004-9793-cdbbf05c3c63/ops/stop mc.ops.restart http://example.com/decca5a5-8952-4004-9793-cdbbf05c3c63/ops/restart mc.ops.suspend http://example.com/decca5a5-8952-4004-9793-cdbbf05c3c63/ops/suspend
id 4696b561-a253-42b4-bd27-7aa4950e0a60 category storage content.size 148251374 link.self virtual-disk.vmdk
id 45a73b80-c957-4ae1-97c6-b70652eba1d1 category network content.vlan 4095 content.dhcp true content.subnet 192.168.0.0 content.netmask 255.255.0.0 content.gateway 192.168.0.1 vnd.com.cisco.cdp true
Ok I've updated the wiki because I'm mostly sold on this. Things do get rather more complicated when you have to parse multiple resources though, which is my main sticking point now... I'm leaning towards the time/space tradeoff of including the ID in each row somehow (in which case parsing into a hash of hashes is trivial again).
I'll not comment on the key space or conflation of objects into one namespace with a category key in this post.
Ok but don't forget to give us some feedback about this...
[1] See.http://en.wikipedia.org/wiki/Initialization_file for details on some
of the variation seen in the wild. There's no formal spec to disambiguate.
Yeah I agree that INI files are not perfect, and for more advanced formatting there's JSON/YAML so there's no point complicating text/plain to the point where it's uninteresting for both audiences. Sam