mustache documentation and recommedations

We use several mustache templates.  Originally we only made little use of 
"template_data".  More recently we are using it more (see below).  Overall 
things are OK either way.

But I'm encountering something where I'd like to see recommendations and 
cannot seem to find any.  Here's part of our "sshd_config" template, that 
doesn't yet use "template_data".

---------------------------------------------------------
{{#classes.g_cs_login_pri}}
{{#vars.g.primary_network_ip}}
ListenAddress {{.}}
{{/vars.g.primary_network_ip}}
{{/classes.g_cs_login_pri}}

{{#vars.dls_cs_ssh.denied_users}}
DenyUsers {{.}}
{{/vars.dls_cs_ssh.denied_users}}
---------------------------------------------------------

Notice how this template definition requires knowledge of the CFE bundle 
names "g" and "dls_cs_ssh".

Now, suppose we refactor the CFE code and rename "dls_cs_ssh" to something 
else.  And suppose, as is quite probable, we overlook (or similarly forget) 
this corresponding change in a different file.  Then this template will 
start failing, as it introduces unexpected errors onto the client 
machines.  The refactoring process is fragile.

Now in theory we can address this by using "template" data.  This would 
allow the "vars" items to be simplified to:

---------------------------------------------------------
{{#primary_network_ip}}
ListenAddress {{.}}
{{/vprimary_network_ip}}

{{#denied_users}}
DenyUsers {{.}}
{{/denied_users}}
---------------------------------------------------------

because the calling bundle can handle the data much more cleanly and 
consistently and, where appropriate, use CFE's "$(this.bundle)".

(We have done such refactoring in other places and it has been very 
successful.)

But you'll also notice how this cannot handle the "classes" information as 
it stands.

Is there a recommended and succinctly documented way to be able to use 
"template_data" to pass not only the "vars" but also the "classes"?

I suspect I could probably hack a way towards inventing my own JSON data 
structure that would somehow capture all this.  But if that is the way I 
should go, then it would be re-assuring to know that this is recommended 
and documented.

-- David Lee

-- 
You received this message because you are subscribed to the Google Groups "help-cfengine" group.
To unsubscribe from this group and stop receiving emails from it, send an email to [email protected].
To view this discussion on the web visit https://groups.google.com/d/msgid/help-cfengine/a27a3806-dd5f-4a13-adde-b190b33828b6n%40googlegroups.com.