[chef] Re: Re: Resource groups

[Maxim Kulkin < >]

As I said, other resources use that service, so it needs to be configured 
immediately. If I make notifications delayed, the restart will be after other 
recipes get executed and thus resources in those other recipes won't be able 
to communicate with that service because of it's misconfiguration.
Say, it's a web service and configuration files determine port and 
credentials to communicate with that service. If those values will change, 
but the service is not restarted, other recipes won't be able to access it.

On Nov 7, 2011, at 22:01, Dmitry Zamaruev wrote:

> Why not get rid of immediate suffix ?
> In that case all :restart attempts will be grouped and service will be 
> restarted only once. But not immediate, some where near to the end of 
> recipe.
> 
> On Mon, 7 Nov 2011 21:58:11 +0400, Maxim Kulkin wrote:
>> Hi everybody,
>> 
>> I'm pretty new to Chef and would like assistance for the following problem.
>> I have a service and several configuration files for it. My other
>> recipes communicate with that service, so it should be configured and
>> ready to use before running them. I have following structure:
>> 
>>  service 'myservice' do
>>    action :nothing
>>  end
>> 
>>  template '/path/to/service/config1' do
>>    ...
>>    notifies :restart, resources(:service => 'myservice'), :immediate
>>  end
>> 
>>  template '/path/to/service/config2' do
>>    ...
>>    notifies :restart, resource(:service => 'myservice'), :immediate
>>  end
>> 
>>  service 'myservice' do
>>    action [:start, :enable]
>>  end
>> 
>> So, I want that if any of two configs change, the service is
>> restarted not later than the second "service" resource. But in
>> configuration that shown above, if both configs change, the service
>> will be restarted two times.
>> 
>> How would you solve this "the Chef-way" ?
>> 
>> After reading through Chef sources I've developed following solution.
>> I have a special resource -- "resource_group":
>> 
>>  service 'myservice' do
>>    action :nothing
>>  end
>> 
>>  resource_group 'myservice_configs' do
>>    template '/path/to/service/config1' do
>>      ...
>>    end
>> 
>>    template '/path/to/service/config2' do
>>      ...
>>    end
>> 
>>    notifies :restart, resource(:service => 'myservice'), :immediate
>>  end
>> 
>>  service 'myservice' do
>>    action [:start, :enable]
>>  end
>> 
>> So, when it is defined, it records all resources (through
>> "method_missing" magic) that are created inside of it. The
>> resource_group resource itself is created after resources in it
>> (that's how Chef works). One resource_group's action triggers, it
>> checks embedded resources'  #updated? method and if any resource was
>> updated, it set's it's own #updated_by_last_action to true (thus
>> triggering notifications).
>> What do you think about this solution? Maybe it could make it into Chef 
>> core?
>> 
>> Thanks,
>> Max
>