节点子进程的cwd无法访问子文件夹

Question

I have problems declaring the path for the current working directory of my child process. I want to execute some R-Scripts and I want to save the results in a folder. But it does not work.

This is working code in my server.js

app.post('/execScript', function (req, res) {
  var childProcess = require('child_process');
  var project = req.body.project;
  var script = req.body.script;
  childProcess.exec('Rscript ../app/projects/'+project+'/Scripts/'+script+'',{cwd: '../app/'}, (err) => {
    if (err) {
      console.error(err);
    }
  })
});

Note, that the cwd saves all results in the /app folder folder.

When I try the following, it stops working and gives me an error.

app.post('/execScript', function (req, res) {
  var childProcess = require('child_process');
  var project = req.body.project;
  var script = req.body.script;
  childProcess.exec('Rscript ../app/projects/'+project+'/Scripts/'+script+'',{cwd: '../app/test/'}, (err) => {
    if (err) {
      console.error(err);
    }
  })
});

I basically want to choose a subfolder of /app and it doesn't work. I get the following error:

{ Error: Command failed: Rscript ../app/projects/das_ist_ein_Test/Scripts/test.R
at ChildProcess.exithandler (child_process.js:211:12)
at emitTwo (events.js:106:13)
at ChildProcess.emit (events.js:191:7)
at maybeClose (internal/child_process.js:885:16)
at Socket.<anonymous> (internal/child_process.js:334:11)
at emitOne (events.js:96:13)
at Socket.emit (events.js:188:7)
at Pipe._handle.close [as _onclose] (net.js:501:12)   killed: false,   

code: 2,   
signal: null,  
 cmd: 'Rscript ../app/projects/das_ist_ein_Test/Scripts/test.R' }

Why is that? Any help would be appreciated !

EDIT: I made sure that the subfolder exists and that i wrote it correctly.

Answer 1

I got it. The error occurs because of the way child processes work in node. When given a cwd, you start in that directory and after that you have to move to the file that needs to be executed from you cwd.