Child Process - Node.js with CasperJs: How to include arguments?

Question

I try to setup a NodeJS child process with arguments. If I run the child process with node it works fine but if I run in with casperjs instead, it doesn't work. I made sure that casperjs is running properly, with another casperjs script which works fine. Here is my setup:

parent.js

var exec = require('child_process').exec;

exec('node child.js', {
    env: {
        number: 123
    }
}, function(err, stdout, stderr) {
    console.log('stdout: ' + stdout);
    console.log('stderr: ' + stderr);
    if (err !== null) {
        console.log('exec error: ' + err);
    }
});

parent2.js

var exec = require('child_process').exec;

exec('casperjs child.js', {
    env: {
        number: 123
    }
}, function(err, stdout, stderr) {
    console.log('stdout: ' + stdout);
    console.log('stderr: ' + stderr);
    if (err !== null) {
        console.log('exec error: ' + err);
    }
});

child.js

var number = process.env.number;
console.log(typeof(number));

number = parseInt(number, 10);
console.log((number));

Output

$ node parent.js
stdout: string
123

stderr: 

$ node parent2.js
stdout: Fatal: [Errno 2] No such file or directory; did you install phantomjs?

stderr: 
exec error: Error: Command failed:

Why can I not use arguments when running the child process with casperjs?

PhantomJS (and CasperJS) don't have the global `process` property. — Artjom B., Jun 15 '15 at 17:07
At least not like this. In PhantomJS you would need to require "system" and use system.env. Just compare the APIs between PhantomJS and node. — Artjom B., Jun 16 '15 at 07:37

score 1 · Answer 1 · edited May 23 '17 at 10:26

Child process runs in a separate process

You have to pass environment variables while you are calling "exec" https://nodejs.org/api/child_process.html#child_process_child_process_exec_command_options_callback

var exec = require('child_process').exec;

exec('casperjs child.js', {
    env: {
        'PATH': '<your path locations with path delimiter>'
    }
},

Example path for windows

c:\\phantomjs\\bin;c:\\casperjs\\bin;C:\\Users\\<username>\\AppData\\Roaming\\npm\\;C:\\Program Files\\nodejs

Double slash \\ used to escape inside string

Example path for linux

/opt/node:/opt/phantomjs/bin:/opt/casperjs/bin

/opt/node only required if you have installed in custom location. As default node will go in default visible PATH

Otherwise add environment variables to /etc/profile

Refer How to set environment variable for everyone under my linux system?

stderr: /bin/sh: casperjs: command not found; exec error: Error: Command failed: /bin/sh: casperjs: command not found — Senju, Jun 15 '15 at 16:24
otherwise try adding the casperjs bin path to system wide environment variables inside /etc/profile using export command — Dickens A S, Jun 15 '15 at 17:03

Child Process - Node.js with CasperJs: How to include arguments?

1 Answers1