handleshells allows for easy calling of command line utilities by processing
command line arguments with handlebars.
It provides:
- Automatic escaping
- Promise-based execution
- Useful template helpers
Example
The following example uses ffprobe to extract metadata from a video file.
const handleshells = require('handleshells')
// A source video file. Notice that the path contains
// a space, which will be automatically escaped.
const videoFile = '/Video Files/video.mov'
// The ffprobe command line. {{ videoFile }} will be substituted.
const command = 'ffprobe -v quiet -print_format json -show_streams {{ videoFile }}'
// Run the command. A Promise will be returned.
handleshells.exec( command, { videoFile } )
.then( ( result ) => {
// Since the command returns JSON to stdout,
// we can access the data directly.
assert.isObject( result.data )
} )API
Functions
compile
Compile a command and return the escaped command line.
Example
assert.equal(
handleshells.compile( 'touch {{ file }}', { file: 'foo.txt' } ),
'touch foo.txt'
)exec
Compiles and then executes a command.
Result
- pid : The process id of spawned command.
- exitCode : The status of the command's exit.
- stdout : The output of the command, usually String.
- stderr : The errors from the command, usually String.
-
data :
stdoutas JSON, if applicable. -
dataerr :
stderras JSON, if applicable.
Example
handleshells.exec( 'echo {{ text }}', { text: 'Hello, world!'} )
.then( ( result ) => {
assert.equal( result.stdout, 'Hello, world!\n' )
} )Template Helpers
args
Spread objects as command line options.
const options = {
a: 'foo',
bar: 'baz qux'
}
assert.equal(
handleshells.compile('{{ args options }}', { options } ),
"-a foo --bar 'baz qux'"
)join
Join strings together into paths.
const dir = 'bar'
, file = 'foo.txt'
assert.equal(
handleshells.compile('{{ join "/tmp" dir file }}', { dir, file } ),
"/tmp/bar/foo.txt"
)