child-process-debug

Convenience methods for debugging child processes in Node.JS. Child processes will be started with --debug if the parent was started with --debug and the children will each get their own increasing port number based off the parent's port number. The default port is 5858. If you add --debug-brk that will also get passed to the children.

Example

var childProcessDebug = require('child-process-debug');

for (var i = 0; i < 4; i++) {
    //if this script wasn't run with --debug this will spawn node example.js [0-3]
    //if this script was run with --debug, this will spawn node --debug=[5859-5862] example.js [0-3]
    childProcessDebug.spawn(['example.js', i]);
}

Methods

spawn([command][, args][, options])

This takes the exact same arguments as child_process.spawn and if the parent had debugging turned on (via --debug), it'll turn on debugging for the spawned child. command is also optional (unlike child_process.spawn) and defaults to process.execPath.

The ChildProcess returned from spawn will have a property called debugPort indicating the debug port chosen for that child or undefined.

fork(modulePath [, args][, options])

This takes the exact same arguments as child_process.fork and if the parent had debugging turned on (via --debug), it'll turn on debugging for the spawned child. Return is the same as spawn above.

nextPort()

Returns the next debug port that comes after the current process's debug port. If the current process doesn't have debug turned on then this will return undefined. This is useful if you're not using spawn and want to specify the --debug=port argument yourself.

exitWithParent(child)

Kill's the spawned child when the parent dies. This will not work if the parent is killed with SIGKILL.

port()

Returns the current process's debug port or undefined if debug is not turned on.

debugBreak()

Returns true if the current process has the flag --debug-brk.

By James Hartig