@gemini/configparser

Parser for gemini configuration files.

Config is described with a combination of a functions:

var parser = root(section({
    system: section({
        parallelLimit: option({
            parseEnv: Number,
            parseCli: Number,
            validate: function() {...}
        })
    }),
    browsers: map(
        section({
            calibrate: option(...),
            windowSize: option(...)
        })
    )
})

There are 4 types of values:

• option({defaultValue, parseCli, parseEnv, validate, map}) - a single scalar option.
  • defaultValue - a default value to use if option is not provided
  • defaultValue(config, currentNode) - a function to compute default value
  • parseCli(value) - a function used to parse command-line arguments
  • parseEnv(value) - a function used to parse environment variable
  • validate(value, config, currentNode, meta) - a function used to validate the option value
  • map(value, config, currentNode, meta) - a function used to transform the option value
• section({sectionName1: valueParser1, sectionName2: valueParser2, ...}) - a section of a values with specified key names. Each option will parsed with appropriate parser function. Any unknown value passed by user will be treated as an error.
• map(valueParser, defaultValue) - a map with any number of user-specified keys. Each value is parsed by valueParser. If set, defaultValue will be used in case of no user-specified data provided.
• root(parser, {envPrefix, cliPrefix}) - creates a root config parsers from specifed parser function. Returns function with signature f({options, env, argv}).