Thanks Luke. So I've been making some notes here:
http://wiki.bob.sh/confluence/display/TECH/Ruby+DSL <http://wiki.bob.sh/confluence/display/TECH/Ruby+DSL>And writing up some working examples: https://github.com/bobsh/puppet-rubydsl-examples <https://github.com/bobsh/puppet-rubydsl-examples>... based on your notes and some digging. You wouldn't be able to take a look and correct me where I've tapped into the wrong part of the API? I realise I'm obviously touching internals that may change ... I just figure if I can figure out how to do it with internals then it shouldn't be hard to extend the DSL. So obviously some of the ways I've done this should really be moved to convenience methods: * Defaults: I presume the capitalisation of the first letter of a missing_method would indicate someone trying to set a default * Vars: not sure how you make this work at the correct scope in ruby for proper 'my_var = "foo"' type sugar ... maybe a wrapper is more appropriate (a bit like create_resource). * Relationships: I'm not sure how to do this yet, looking at the AST::Relationship bit there is a lot going on so I imagine I tap that, but how I do that without extending the dsl code itself is not obvious (so obviously I'm going to try that :-). How would one go about extending it to deal with top scope? I'm guessing somehow you need to be able to populate @__created_ast_objects__ directly right from ResourceTypeAPI? ken. On Friday, December 10, 2010 6:47:42 AM UTC, Luke Kanies wrote: > > On Dec 8, 2010, at 11:09 AM, Ken Barber wrote: > > (cross posting here as I originally posted in puppet-users - I figure the > question is more of a dev one then for puppet-users) > > > Hi everyone, > > I'm experimenting with converting some of my live puppet content to > Ruby DSL and have found a few gaps I wouldn't mind some advice on. I'm > not sure how many of you have already experimented in this arena yet. > > I've already read Dan Bode's excellent blog article on the subject: > http://www.puppetlabs.com/blog/ruby-dsl/ > > I know the Ruby DSL is quite new - but I figured perhaps some of these > items deserve to be tickets (or perhaps documented) and I thought I'd > ask first :-). > > Thanks for testing this. As you say, it's still quite new, and definitely > incomplete, but as with most things we do, I wanted to get a simple thing > out and in the wild rather than wait for perfection before shipping. This > kind of feedback is exactly what we need (although of course patches are > even better). > > 1. Defaults > > How do I set defaults in Ruby DSL? For example what is the ruby DSL > equivalent to this: > > Service { > hasstatus => true > } > > This is one of the things I left out of my initial implementation. > > You might be able to figure out how to add it by patching one of the files > in lib/puppet/dsl. > > 2. Top scope > > I notice the convenience methodology does not work at 'top scope' for > example > this will fail: > > file "/tmp/zzz", :content => "foo" > > But this will not: > > node "default" do > file "/tmp/zzz", :content => "foo" > end > > Is there a proper way to call resources without using the convenience > methods? Or > perhaps is there a way to define elements that reside in top scope? > > I made a decision when I did this not to pollute the top namespace - both > for cleanliness, and also for simplicity of implementation. This has come > up a few times, though, so it's something that I'm happy to revisit. > > 3. Class resource > > I think Dan Bode already raised this as a bug: > https://projects.puppetlabs.com/issues/5236 > > The following returns an error 'method_missing': > > hostclass :foo do > notify "bar" > end > node "default" do > hostclass "foo", :stage => "baz" > end > > This is because hostclass has not been defined as a convenience method > it would seem. Just like issues 2 If someone knows > a way to call a resource directly without requiring the convenience > method that would be a decent enough work-around. > > Hmm. It should be, but it looks like this is failing somewhere and has > been marked as a high priority bug. :/ > > 4. exec Resource > > The 'exec' resource as a convenience method is overlapping with the > ruby 'exec' > method. So if you do this: > > node "default" do > exec "ls", :command => "/bin/ls" > end > > You get: > > can't convert Hash into String on node obelisk.usr.bob.sh > > Returned from the Kernel.exec call. > > You should be able to use 'create_resource :exec, ...' here. > > 5. Referencing other resources > > I'm not quite clear how to reference other resources that already > exist. This is obviously a problem for the 'require' attribute: > > node "default" do > package "foo", :ensure => "installed" > service "foo", :enable => "true", :ensure => "running", :require > => ??? > end > > I believe the internal implementation allows you to do 'require => > [:package, "foo"]'. I couldn't find a reasonable syntax for this, without a > lot more work making, e.g., Package["foo"] work, which was my ideal. > > 6. Chaining Resources > > Is there a syntactical equivalent to this in Ruby DSL yet? For > example: > > Stage[pre] -> Stage[main] -> Stage[post] > > Without knowing how to solve 5 I'm kind of stuck when it comes to > defining dependencies :-). > > There isn't. > > The DSL is obviously still a subset of the "full" Puppet language (ironic, > given how small the language is). > > > -- > Computers are not intelligent. They only think they are. > --------------------------------------------------------------------- > Luke Kanies -|- http://puppetlabs.com -|- +1(615)594-8199 > > > -- You received this message because you are subscribed to the Google Groups "Puppet Users" group. To post to this group, send email to puppet-us...@googlegroups.com. To unsubscribe from this group, send email to puppet-users+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/puppet-users?hl=en.
