filter-argv

Utilities for filtering raw process.argv content (i.e. arguments passed via the CLI). Easily extract or exclude flag arguments (e.g. -v, --debug), assignment arguments (e.g. name=meeka, --age=14), standard args (e.g. create-component, load, repl), lonely dashes ('-', '--'), and any combination of argument types.

##Quick examples

input:
    npm run my-script -- create-component HelloWorld --verbose --debug name=meeka --type=puppy

in my-script:

    const { filterArgv } = require('filter-argv');

    filterArgv();
        // => ['my-script', 'create-component', 'HelloWorld', 'name=meeka', '--type=puppy']

    filterArgv(process.argv);
        // => ['my-script', 'create-component', 'HelloWorld', 'name=meeka', '--type=puppy']

    filterArgv({ keepLonelyDashes: true });
        // => ['my-script', '--', 'create-component', 'HelloWorld', 'name=meeka', '--type=puppy']

    filterArgv({ keepLonelyDashes: true, assignments: 'none' });
        // => ['my-script', '--', 'create-component', 'HelloWorld']

    filterArgv({ assignments: 'noflag' });
        // => ['my-script', 'create-component', 'HelloWorld', 'name=meeka']

    filterArgv({ standardArgs: false, assignments: 'all' });
        // => ['name=meeka', '--type=puppy']

    filterArgv({ flags: true, standardArgs: false });
        // => ['--verbose', '--debug', 'name=meeka', '--type=puppy']

    filterArgv({ flags: true, standardArgs: false, assignments: 'noflag' });
        // => ['--verbose', '--debug', 'name=meeka']

    filterArgv({ flags: true, standardArgs: false, assignments: 'noflag', keepLonelyDashes: true });
        // => ['--', --verbose', '--debug', 'name=meeka']

##Type signatures

filterArgv: (processArg?: Array<String>, opts?: Options) => Array<String>

• processArg: optional parameter containing a string array, presumably process.argv or a modified form of it. However, any array of strings can be used - it is not limited to process.argv

  • by default, returns a duplicate of the array with all flag arguments removed.
  • if no value is passed, defaults to the current value of process.argv
  • note: if you're parsing process.argv, for convenience you can simply pass in the Options object at this argument. The module will detect it, assign options correctly, & automatically parse the contents of process.argv.

• opts: (type Options): Provides options for filtering the process arguments. By default, excludes flag CLI args (e.g. -a, --gbr), excepting those used for assignment (e.g. it keeps args like --name=meeka, -type=puppy).

  • opts.flags: true | false
    • Default: false
    • if true, keep flags in the returned process.argv object
  • opts.standardArgs: true | false
    • Default: true
    • if true, keep standard (non-flag, non-assignment) arguments in the output (e.g. meeka, puppy)
  • opts.assignments: 'all' | 'none' | 'no-flags
    • Default: all
    • 'all': keep all assignment args (e.g. --name=meeka, age=43, --etc=ok)
    • 'none': exclude all assignment args
    • 'no-flags': exclude assignment args that are also flags (e.g. --name=meeka)
  • opts.keepLonelyDashes: true | false
    • Default: false
    • if true, keep isolated dashes ('-', '--', '---') in the output

Examples

//my-script.js
const { filterArgv } = require('filter-argv');

const contentArgsOnly = filterArgv();
console.log(contentArgsOnly);

The output of the above example will vary based on how the script was run (from the terminal). e.g.:

input:   node my-script.js --verbose
output:  ["node", "my-script.js"]

input:   node my-script.js
output:  ["node", "my-script.js"]

input:   my-script.js --verbose create-component SidebarGrid
output:  ["my-script.js", "create-component", "SidebarGrid"]

input:   my-script.js --verbose create-component SidebarGrid --debug
output:  ["my-script.js", "create-component", "SidebarGrid"]

input:   my-script.js --verbose create-component --name=SidebarGrid --debug
output:  ["my-script.js", "create-component", "--name=SidebarGrid"]

Other filterArgv examples :

const contentArgsOnly = filterArgv(process.argv); // mainly for explicitness
const contentArgsOnly = filterArgv(['hello', '--flag', 'custom', 'array', 'example']); 
const contentArgsOnly = filterArgv({
    assignments: 'noflag',
    flags: true,
    standardArgs: false,
    keepLonelyDashes: true
}); 

getStandardFlags: (argv?: Array) => Array

Convenience function to return a list of the flags in an arguments list. e.g.

getStandardFlags(['--verbose', 'reth', '--asdf=fghj', '--debug', 'boo']);
    // => ['--verbose', '--debug']

getAssignmentArgsOnly: (argv?: Array) => Array

Convenience function to return a list of the assignment args in an arguments list. e.g.

getAssignmentArgsOnly(['--verbose', 'reth', '--asdf=fghj', '--debug', 'boo', 'type=Bear']);
    // => ['--asdf=fghj', 'type=Bear']