Rewrite of formula

[tomduijf]

Hi all,

I imagine rewrites of existing formulas are not taken lightly, and they shouldn't.
There were many great idea's taken from the current formula, which will still work. Some things did change that makes this PR not backward compatible with current pillar.

This is an initial PR, i'd very much like some feedback on if we want this at all, and possible improvements. See todo below.

So, what does this bring? Some of these items are also present in the current version.

• Renaming '_' -> '-' for option and statement names is still here.
• All config blocks (declarations in dhcpd) are printed using a macro.
  • This allows easier mixing of declarations inside declarations. dhcpd gives a lot of freedom in buiiding a configuration. The current formula is very limited in this
• Available options and statements are defined in lists. This allows for
  • shorter code
  • automatic quoting, if the statement / option needs it.
  • easier extending supported statements / options
  • it doesn't safeguard setting invalid statements in invalid places anymore. You can now put any statement anywhere (drawback of the lists approach).
• type of custom_options are tracked in the big option list, allowing these to be automatically quoted as well.
• option spaces. Well these are pretty much custom_options, but these are grouped together nicely
• much more statements, declarations and options supported.
• all options and statements can be either single key/val pairs or key/list items (useful array/list definitions like option domain-name-servers
• special statements like allow, deny, set, `match, etc are repeated when values are in list form
• failover options that may only be set for primary, are not printed for secondary role

Incompatibility with the current formula:

• failover peer primary/secondary are set using role:
• all option <something> statements require to be set under options: dict
• customized_options -> custom_options

Todo:

• more testing
• cleanup some of the jinja code
• optimize some stuff (like use |join(', '), etc)

Probably forgot to mention several things.

This was quite a bit of work, especially the jinja code, getting to the eventual imports / macro combination as a solution for dealing with the blocks, custom option tracking, and passing configuration.
Hope you like!

[mthibaut]

I am in the process of adding testing to dhcpd-formula. Next I would like to incorporate your changes and add IPv6 support.

[tomduijf]

Hi @mthibaut

Sounds great! I'd be happy to help with testing/reviewing if you want.

Mind passing a little credit back my when submitting? (took me quite some effort)