An LWRP is a part of a cookbook that is used to extend the chef-client in a way that allows custom actions to be defined, and then used in recipes in much the same way as any platform resource.
An LWRP is a part of a cookbook that is used to extend the chef-client in a way that allows custom actions to be defined, and then used in recipes in much the same way as any platform resource. A LWRP has two principal components:
- A lightweight resource that defines a set of actions and attributes
- A lightweight provider that tells the chef-client how to handle each action, what to do if certain conditions are met, and so on In addition, most lightweight providers are built using platform resources and some lightweight providers are built using custom Ruby code
Once created, a LWRP becomes a Ruby class within the organization. During each chef-client run, the chef-client will read the lightweight resources from recipes and process them alongside all of the other resources. When it is time to configure the node, the chef-client will use the corresponding lightweight provider to determine the steps required to bring the system into the desired state.
Where the lightweight resource represents a piece of the system, its current state, and the action that is needed to move it to the desired state, a lightweight provider defines the steps that are required to bring that piece of the system from its current state to the desired state. A LWRP behaves similar to platform resources and providers:
- A lightweight resource is a key part of a recipe
- A lightweight resource defines the actions that can be taken
- During a chef-client run, each lightweight resource is identified, and then associated with a lightweight provider
- A lightweight provider does the work to complete the action requested by the lightweight resource
You can read more about how to build custom lightweight resources on the Chef docs.
