JSON parsing functions

[andymuldowney]

We use confd with etcd. In etcd, we often store values in JSON. We added two very basic mapped functions to the template parser that allows use to handle JSON values inside of templates - one for objects, and one for arrays.

Usage example:

{{with $c := JsonUnmarshalObject $container.Value}}
  {{printf "%s:%.0f" $c.ip $c.ports.web}};
{{end}}

[kelseyhightower]

Very nice!

[kelseyhightower]

Thanks for the PR, I'm be speaking at events related to OSCON, and I'll get a chance to review this later in the week.

[carmstrong]

Awesome! Could we add these to the template functions documentation?

[carmstrong]

This is working great for me:

core@deis-1 ~ $ cat templates/something.conf.tmpl
BROKER_URL = 'redis://{{ with $obj := JsonUnmarshalObject .deis_locks_cache }}{{ printf "%s:%s" $obj.host $obj.port }}{{ end }}/0'
core@deis-1 ~ $ ./confd -onetime -config-file=/home/core/confd.toml
2014-08-01T04:49:18Z deis-1 ./confd[964]: INFO Target config /home/core/something.conf out of sync
2014-08-01T04:49:18Z deis-1 ./confd[964]: INFO Target config /home/core/something.conf has been updated
core@deis-1 ~ $ cat something.conf
BROKER_URL = 'redis://172.17.8.100:6379/0'

[kelseyhightower]

Ok we have a few of these PRs that add json functions. We should merge them up into a single PR and add them 0.5.x and 0.6.x

[kelseyhightower]

@andymuldowney @carmstrong I'm going to merge #111 once tests pass and update the docs. Closing this out, lets collaborate on #111 for JSON support.

[chrisjenx]

Could someone add an example to the docs for this?