[chef] Re: Re: Templates don't fail when values are missing

[Mathias Lafeldt < >]

Peter,

You might want to use Hash#fetch in your template, which raises a
KeyError if a key can't be found (thereby aborting the chef run).

See http://www.ruby-doc.org/core-1.9.3/Hash.html#method-i-fetch

-Mathias


On Mon, Apr 15, 2013 at 9:45 PM, AJ Christensen 
<
 >
 wrote:
> In ruby, Hash[nil] => nil; so, explicitly bind your hash keys to
> 'variables' in the template and then check for presence of the ivar.
>
> An alternate workaround: <%= if @property.key?('foobar') %>
>
> Cheers,
>
> AJ
>
>
> On 16 April 2013 06:48, Peter Loron 
> <
 >
>  wrote:
>> I have a large (hundreds of properties, dozens of templates) set of 
>> templates I'm porting from Nant to Chef. The properties in the old system 
>> are scattered across multiple files and while aggregating the properties 
>> into data bags and adjusting the templates, I have missed some values.
>>
>> The call in the recipe to merge each template with the properties from the 
>> data bags works, but values that are not present in the hash are simply 
>> empty in the generated template. The substitution fails silently.
>>
>> For example, if I have this in the template:
>>
>> <foobar value="<%= @property['foobar'] %>" />
>>
>> … and the 'foobar' key/value pair is not present, I wind up with this in 
>> the generated file:
>>
>> <foobar value="" />
>>
>>
>>
>> Is there any way to get Chef to throw a warning or error in this case?
>>
>> Thanks.
>>
>> -Pete