CommandLineFlag

An easy tool for generating CLI and controling command params

version: 0.0.6

Date: 2019/1/17

Support parsing command line arguments and outputting doc quickly

中文文档

Feature

• easy api, fast CLI initialization
• flag module could parse command line arguments and call registered function
• output module could output formatted helpInfo doc。
• absolute seperation among modules although you can inject output instance to flag instance to generate helpInfo about command or option conveniently
• similar api to commander ，nearly all api support chain call(flag's run method and output's render method not support)

Directory tree

    ├─example  // demo
    |─src       
    │  └─core  // source code
    └─test     // test

Usage

1. yarn add @alanchenchen/commandlineflag or npm install --save @alanchenchen/commandlineflag
2. npm package export an object including two methods:
   • flag resolve command line arguments
   • output output formatted helpInfo doc

Options

flag module

flag method

method returns a Flag instance

Flag instance method

1. param basic function that parse cmd arguments, returns a Flag instance。Function arguments：

   • opts [Object]
     • index [Number] cmd argument index，default is undefined
     • flag [String] cmd argument flag name，default is undefined
     • action [Function] callback function while matching cmd argument successfully
       • first argmuent is an object inculding two keys，index and param
       • second argument is an array that show a list including all cmd arguments
       • callback function trigger rule：
         1. only index, if cmd argument of index exsit, trigger
         2. only flag, if cmd argument of flag exsit, trigger. flag should not match the index.
         3. both index and flag, should match cmd argument of index and cmd argument of flag, trigger

2. command parse command (index is 0)，returns a Flag instance。Function arguments：

   • flag [String] command name，required
   • desc [String] command helpInfo
   • action [Function] callback function while matching cmd argument successfully

   if there are two arguments，the second one must be action，if three，the second one must be desc，the third one must be action。

3. option parse option (only flag)，returns a Flag instance。Function arguments：

   • flag [String] option name，required
   • desc [String] option helpInfo
   • action [Function] callback function while matching cmd argument successfully

   if there are two arguments，the second one must be action，if three，the second one must be desc，the third one must be action。

4. version parse version option，returns a Flag instance and output version message。Function arguments：

   • desc [String] version message
   • flag [String] version flag，default is '-V | --version', you could rewrite it

5. register register prototype method globally，returns a Flag instance。command、option and version method are all implemented by register。Function arguments：

   • name [String] method name，required
   • handler [Function] trigger function while you use the register method, usually use param method to implenment it。Such as ：

     const program = new Flag()
     program.register('help', info => {
         // if you want help method to be chain called，return program.param() or program
         return program.param({
             flag: '--help',
             action() {
                 console.log(info)
             }
         })
     })
     
     // now，any Flag instance could include help method 
     program.help('help info')
     

6. inject inject Output instance，would output doc while running，returns a Flag instance。Function arguments：

   • OutputInstancen [Object] Output instance which would be injectd，required

7. run run the Flag instance, no return value。

must call run method otherwise the cmd arguments would not be parsed

output module

output method

method returns a Output instance。

Output instance method

1. writeUsage output usage info，returns a Output instance。Function arguments：
   • usageInfo [String] main usage info
   • description [String] usage description bellow usageInfo，optional
2. writeCommands output command helpInfo，returns a Output instance。Function arguments：
   • if there is only one argument:
     • info [Array] array item is an object including title(command name) and desc(command description)
   • if there are two arguments:
     • commandInfo [String] command name
     • description [String] command description
3. writeOptions output option helpInfo，returns a Output instance。Function arguments：
   • if there is only one argument:
     • info [Array] array item is an object including title(command name) and desc(command description)
   • if there are two arguments:
     • optionInfo [String] option name
     • description [String] option description
4. write info at the end of doc，returns a Output instance。Function arguments：
   • desc [String] customed info ，support multiple arguments
5. render generate helpInfo doc，returns a string of doc。Function arguments：
   • isShowLog [Boolean] whether output doc to stdout，default is true

must call render method otherwise the doc would not be generated. If you inject Output instance to Flag instance, render method is not necessary since Flag instance implement render method

Example

see hotload-cli

Unit test

• there is only one test about command()、option()and version() of Flag instance
• the test framework is mocha，if you want to add unit tests，follow ：
  1. git clone git@github.com:LionOcean/CommandLineFlag.git
  2. add js which should have *.test.js extname
  3. yarn或npm install install devdependences mocha
  4. npm test open terminal to see result

license

• MIT