Cliquet

cliquet is a tool for building CLI applications from a single configuration object definition, it can:

• parse options from command line arguments in long (--opt) and short (-o) forms.
• parse settings from a configuration file.
• get defaults from an instance of the configuration object.
• get a merged configuration object prioritizing in the following order: command line arguments, configurations, and defaults.
• build a help message detailing each option, their types, default values, and usage.

cliquet is not designed to take over, resolve, and/or automate every possible use case of a command line application, but rather serves as a non-intrusive tool to simplify the creation of one.

Documentation

The API reference is available here.

Usage

# Define the configuration object
type Choice = enum yes, no, maybe

type Configuration = object
  flag    {.help: "flags".}                           : bool
  str     {.help: "String arguments".}                : string
  number  {.help: "Float or int arguments".}          : int
  options {.help: "Enums work too".}                  : Choice
  list    {.help: "Lists are also supported".}        : seq[string]
  short   {.help: "Short options", shortOption: 's'.} : bool

# Initialize `cliquet` with the default settings
let defaults = Configuration(
  flag: false,
  str: "Hello",
  number: 10,
  options: Choice.yes,
  list: @["one", "two", "three"],
  short: false
)

var cliquet = initCliquet(defaults)

# Command line arguments are parsed up to the first non-option argument, returning the remaining ones
let remainingArgs = cliquet.parseOptions(commandLineParams())

# A command line for this example looks like this
./example --flag --str="Hello World" --number=10 --options=Maybe --list=one,two,three -s

# Parse configurations, typically obtained from a configuration file
cliquet.parseConfig(readFile("config.ini"))

# A configuration file for this example looks like this
flag 
str     = Hello World
number  = 10 
options = Maybe 
list    = one,two,three
short
# Lines preceded by # are ignored

# Get the final merged configuration object
let configuration = cliquet.generateConfig()

# Get a help message for the defined configuration
let help = cliquet.generateHelp()

# The help message looks like this:
Options     Type                          Default                Help
--flag      true|false                    false                  flags
--str       text                          Hello                  String arguments
--number    int number                    10                     Float or int arguments
--options   yes|no|maybe                  yes                    Enums work too
--list      ',' separated list of text    "one", "two", "three"  Lists are also supported
-s,--short  true|false                    false                  Short options

(Tentative) Roadmap

• Generate default config file contents
• Allow excluding some config from the options, or the config file
•  Generate 'usage' message
• Required options
• Parse non-option command line arguments?
• Support for environment variables?
• Multiple lines support for help messages?
• Support other configuration formats?
• Support overriding the type name in the help message?