# Do It
Elixir Command Line Interface Framework.
A framework that helps to develop command line tools with Elixir.
**_Do It_** have two main components:
* `DoIt.Command` - represents a single command.
* `DoIt.MainCommand` - find all defined commands in project and generate all functions to match all commands in a single module, must be used as `main_module` in `escript` definition.
The commands `version` and `help` are automatic generated for the client.
The version number is obtained from `mix.exs` or option `version` in `MainCommand`.
So, if you have a client named `cli`, you can type `cli version` and `cli help` to get the version number and the list of commands respectively from the client.
### Command
We can define a new command as follows:
```elixir
defmodule Hello do
use DoIt.Command,
description: "Useless hello command"
argument(:message, :string, "Say hello to...")
option(:template, :string, "Hello message template", alias: :t, default: "Hello <%= @message %>!!!")
def run(%{message: message}, %{template: template}, _) do
IO.puts EEx.eval_string(template, assigns: [message: message])
end
end
```
A `help` option is automatically added to the command to describe its usage.
```shell script
$ ./cli hello --help
Usage: cli hello [OPTIONS] <message>
Useless hello command
Arguments:
message Hello nice message
Options:
--help Print this help
-t, --template Hello message template (Default: "Hello <%= @message %>!!!")
```
Use `DoIt.Command` and provide a required `description`, the command name is the module name, you can override that name using the `name` option.
```elixir
defmodule Hello do
use DoIt.Command,
name: "olleh",
description: "Useless hello command"
...
end
```
### MainCommand
It generates functions matching all defined commands in the project, delegating the call to the matched command.
A `MainCommand` could be defined as follows:
```elixir
defmodule Cli do
use DoIt.MainCommand,
description: "My useless CLI"
end
```
## Installation
The package can be installed by adding `do_it` to your list of dependencies in `mix.exs`:
```elixir
def deps do
[
{:do_it, "~> 0.2.0"}
]
end
```
## License
DoIt is released under the Apache License 2.0 - see the [LICENSE](LICENSE) file.
