如何通过node-pty设置$ PATH作为在节点中扩展进程的一部分？

Question

We are trying to encapsulate a very old command-line application which has these requirements:

1. the application must be launched from the location of our data files (ie the CWD is the data file directory)
2. the application exists at a location not in the default $PATH
3. the application launches sub-processes that expect the application path to be in $PATH
4. Due to 2 & 3, the application's path must be manually added to $PATH prior to launching it

So the normal way to run it is to cd to the data directory, add the application directory to the $PATH, and then run the application. We can't just launch the application by its full path -- the $PATH must be set because the application expects to call other sub-processes in the same directory. We don't have the ability to modify the application or its requirements.

The problem is this: how do I encapsulate the setting of $PATH and the launching of the application when spawning a process in node via node-pty.

var pty = require('node-pty');
// myapp lives in /usr/bin/app/
var term = pty.spawn("myapp", [], {
        cwd: '/usr/data/mydata'
      });

In short, I want the spawn to happen in the /usr/data/mydata directory, have /usr/bin/app/ added to $PATH, and myapp to get spawned, all in one shot.

Answer 1

PATH is an environmental variable, so setting it with the env parameter should work.

var pty = require('node-pty');
// myapp lives in /usr/bin/app/
var term = pty.spawn("myapp", [], {
  cwd: '/usr/data/mydata',
  env: { PATH: '/usr/data/app:' + process.env.PATH }
});