spawn-series

If you want to spawn commands, while blocking the next command untill earlier finishes execution use this module. This uses child_process.spawn for spawning the process.

Usage

npm install --save spawn-series

API

spawnSeries(commands [, finish [, foreach]] )

Arguments

commands

This should be an array of objects in the format:

[
    {
        command: 'command1' // command to execute
        args: ['arg1', 'arg2', 'arg3'], // optional arguments for command,
        options: {
            // options for child_process.spawn
        },
        when: function (i, cmdObj) { // optional function to decide if command should be executed
            return evaluateCondition();
        }
    },
    {
        command: 'command2',
        args: ['arg1', 'arg2', 'arg3']
    },
    {
        command: 'command3'
    }
]

Each object should contain a
command to be run and may contain
args [optional] an array of arguments for command
options [optional] options to be passed to child_process.spawn
when [optional] a function that evaluates a condition to whether to run or skip this command execution.

finish

An optional callback function to be called when spawn-series finishes execution.

Signature: function (code, i, cmdObj)
Arguments:
If all commands finish successfully, code will be 0.
Else if one of the commands fail:
code: exit code of failed command
i: failed command number in commands array
cmdObj: failed command object from commands array

foreach

An optional callback function that is called when each command in commmands array is spawned.

Signature: function (child, i, cmdObj)
Arguments:
child: current child process spawned
i: current command number in array passed to spawnSeries's as first argument
cmdObj: current command object in array passed to spawnSeries's as first argument

Use this method attach listeners to the child process.

Example

var spawnSeries = require('spawn-series');
 
spawnSeries(
    [
        {
            command: 'git',
            args: ['clone', '[e-mail]:someid/somerepo.git'],
            options: {
                stdio: 'inherit'
            }
        },
        {
            command: 'npm',
            args: ['install'],
            options: {
                cwd: './some-repo',
                stdio: 'inherit'
            },
            when: function () {
                return fs.existsSync('./some-repo/package.json');
            }
        },
        {
            command: 'bower',
            args: ['install'],
            options: {
                cwd: './some-repo',
                stdio: 'inherit'
            },
            when: function () {
                return fs.existsSync('./some-repo/bower.json');
            }
        }
    ],
    function (code, i, cmdObj) {
        //finish callback
        if (code === 0) {
            console.log('Finished setting up some-repo');
        } else {
            console.log('Error while setting up some-repo in command: ' + cmdObj.command);
        }
    },
    function (child, i, cmdObj) {
        //foreach callback
        console.log('Starting: ' + cmdObj.command + ' ' + cmdObj.args.join(' '));
        child.on('close', function (code) {
            console.log('Finished: ' + cmdObj.command + ' ' + cmdObj.args.join(' '));
        });
    }
)