# dhall-ansible `dhall-ansible` contains [Dhall][dhall-lang] bindings to [Ansible][Ansible], so you can generate Ansible playbooks from Dhall expressions. This will let you easily typecheck, template and modularize your Ansible playbooks. See the [dhall-kubernetes][dhall-kubernetes] demonstration for a concrete example of why you might want to do this. ## Contribute Pull Request are welcome. Only the `types/` files or the `scripts/generate.py` script needs to be updated, then run the `make` command to update the schemas and defaults. For example to add new module, create a file name `types/modules/${module-name}.dhall` and `make` will update the `types/task.dhall` and schemas files. Only the simplified type for `play.hosts`, `play.roles`, `play.vars` and `tasks.vars` is currently supported. The alternative are: * Support only the complex type (List Text, List RoleDict, JSON/Type vars). * Support both using an Union <Simplified | Complex> form. ## Example ```dhall {- ./examples/demo.dhall -} let Ansible = https://raw.githubusercontent.com/TristanCacqueray/dhall-ansible/master/package.dhall in [ Ansible.Play::{ , hosts = "localhost" , vars = Some (toMap { var_name = "var_value" }) , tasks = Some [ Ansible.Task::{ , debug = Some Ansible.Debug::{ msg = Some "Hello world" } } , Ansible.Task::{ , name = Some "Installing package" , become = Some True , package = Some Ansible.Package::{ , name = "emacs-nox" , state = "present" } } ] } ] ``` ```yaml # dhall-to-yaml --file examples/demo.dhall - hosts: localhost tasks: - debug: msg: Hello world - become: true name: Installing package package: name: emacs-nox state: present vars: var_name: var_value ``` ## Extend To use custom modules, the Task type may be extended with the [//\\ operator][type-operator]: ```dhall {- ./examples/custom.dhall -} let Ansible = ../package.dhall let MyModule = { Type = { attribute : Bool }, default = {=} } let Task = { Type = Ansible.Task.Type //\\ { my-module : Optional MyModule.Type } , default = Ansible.Task.default // { my-module = None MyModule.Type } } in [ { hosts = "localhost" , tasks = [ Task::{ , name = Some "my-module usage" , my-module = Some MyModule::{ attribute = True } } ] } ] ``` ```yaml # dhall-to-yaml --file examples/custom.dhall - hosts: localhost tasks: - my-module: attribute: true name: my-module usage ``` ## Changes Frozen package is available in the tag commit. ### 0.1.0 - Initial release [dhall-lang]: https://dhall-lang.org [Ansible]: https://ansible.com [dhall-kubernetes]: https://github.com/dhall-lang/dhall-kubernetes [type-operator]: https://docs.dhall-lang.org/references/Built-in-types.html#id70