argparce

An easy argument parser for nodejs

Install

npm install --save argparce

Usage

const ArgParser = require('argparce');

API Reference

ArgParser.parse(args, options)

• args <Array> an array of arguments

• options <Object>

  • args <Array> an array of argument flag definitions
    • <Object>
      • type <string> The data type of the argument.
        • Valid types are 'string', 'integer', 'uinteger', 'float', 'ufloat', 'url'.
        • 'boolean' arguments do not require a following argument and can be called as --arg (which gives the value true) or --arg=false (which gives the value false)
        • all other argument types must be called either as --arg=value or --arg value
      • name <string> The full name of the argument.
        • Example: 'connect-timeout' will create an argument named --connect-timeout
      • short <string> The short name of the argument.
        • Example: 'v' will create a short argument named -v
      • default <Any> The default value of the argument
  • maxStrays <integer> the maximum number of stray (not attached to flags) arguments allowed, or -1 to allow an infinite amount. Default: 0
  • unmappedArgsDefault <string> the default behavior for handling unrecognized argument flags. Default: null
    • null unrecognized flags will cause an error
    • 'stray' unrecognized flags will be added as stray arguments.
    • 'boolean' unrecognized flags will be read as boolean arguments and added to args in the result
    • 'string' unrecognized flags will be read as string arguments (in the form --arg=<string>)
  • stopAtError <boolean> stop parsing when an error is encountered.
  • stopIfTooManyStrays <boolean> stop parsing when a stray is encountered that can't be added due to maxStrays, and doesn't add an error to errors in the result.
  • errorExitCode <integer> An exit code to exit with if errors occur during parsing, or null to not exit. Default: null

• Returns <Object>

  • args <Object> An object mapping of argument names to their values
  • errors <Array> An array of string messages for errors that occurred during parsing.
  • endIndex <integer> The args index where parsing stopped, or args.length if parsing completed without stopping
  • strays <Array> An array of stray arguments. Stray arguments are command line parameters that didn't match any arguments defined in options.args. Array is empty by default unless options has some non-default values.
  • stopped <boolean> Indicates if parsing was stopped before finishing

Parses the command line arguments with the given options

• Example:

  Javascript Code:

  // test.js
  var result = ArgParser.parse(process.argv.slice(2), {
      args: [
          {
              type: 'boolean',
              name: 'verbose',
              short: 'v'
          },
          {
              type: 'uinteger',
              name: 'request-timeout',
              default: 10000
          },
          {
              type: 'string',
              name: 'name'
          }
      ],
      maxStrays: 2,
      stopAtError: true
  });
  console.log(result);

  Command Line:

  node test.js --request-timeout=23470 "bing" --verbose "bang" --name "hello world" "bong"

  Output:

  {
      "args": {
          "request-timeout": 23470,
          "verbose": true,
          "name": "hello world"
      },
      "strays": ["bing", "bang"],
      "errors": ["invalid argument bong"],
      "stopped": true,
      "endIndex": 6
  }

ArgParser.validate(type, value)

• type The argument type to valid
  • Valid types are 'string', 'integer', 'uinteger', 'float', 'ufloat', 'url'.
• value The value to validate against the type
• Returns: The validated value, or null if validation failed

Validate a value against a type.