diff options
| -rw-r--r-- | docs/dev/design_documents/compile_converge_mode.md | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/docs/dev/design_documents/compile_converge_mode.md b/docs/dev/design_documents/compile_converge_mode.md new file mode 100644 index 0000000000..e7b4eecea8 --- /dev/null +++ b/docs/dev/design_documents/compile_converge_mode.md @@ -0,0 +1,38 @@ +--- +title: Data Collector +--- + +# Compile Converge Mode + +## + + + +## Special Considerations: `chef_gem`, `hostname` and chef-sugar + +The `chef_gem` and `hostname` resources take a `compile_time` property which can be used to force the resource +to run at compile time. Presently this API is limited to those two resources. + +Historically the `chef_gem` was forced to run at compile time always. This was eventually realized to be a poor +design since native gems being installed at compile time would force the installation of compilers at compile +time and created a large race to push more and more resources to compile time. This default was eventually +flipped so that it ran at converge time, but it was necessary to introduce the `compile_time` property to deal +with that transition. It is generally recommended to not set this property to true. + +The `hostname` resource copies that implementation. Since the `hostname` resource changes the hostname on the box +and then re-runs `ohai` and loads new state into the node object it is forced to run at compile time, before any +resources are converged, and before later resources are parsed at compile time. This avoids having to lazy every +`node[:fqdn]` (or `node[:machinename]` which is a better attribute to use) reference in every subsequent resource. +The same `compile_time` flag is introduced there in order to override this. It is not recommended to set this +property to false. + +The `chef-sugar` gem adds the syntax to force any resource to compile time via the `at_compile_time` helper method: + +```ruby +at_compile_time do + package "apache2" +end +``` + + + |