how to escape whitespace in Node-RED exec node command

Question

Situation:

In my Node-RED flow there is a call to another program where I use the exec node. The arguments are set-up in a function node and passed as the msg.payload to the exec node. This works fine and returns the expected results as long as the command has no space in it.

Problem:

A customer cannot use the call to the command on his system, because the path tp the installation of the program contains a whitespace.

What I tried and didn't work:

1. Escaping the whitespace with ^ as read in another question: /opt/path^ toProgram^ directory/program
2. Escaping the whitespace with \\: /opt/path\\ toProgram\\ directory/program
3. Quoting the whole string with "": "/opt/path toProgram directory/program"
4. Quoting the whole string and escaping the whitespace: "/opt/path\\ toProgram\\ directory/program"
5. Quoting the whole string with '': '/opt/path toProgram directory/program'
6. Leaving the command line empty/""and combining any of the above points with its arguments to one string (in the function node that sets up the arguments for that exec node) and passing it on as the msg.payload -> input parameters in the exec node config panel. No Success.

What's not the problem:

• The program itself works fine, on mine and on the customers system, it's only the path that is different

• Other than that specific command string with whitespace, the configuration of the exec node and its msg.payload ( = input parameters or arguments) as well as the "use spawn() instead of exec()?" is fine and works

Request

Is there any other way to escape the whitespace that I'm not aware of so the path to the program can be found? From my understanding the whitespace is interpreted as a separator for the input arguments, which it should be, but not on the command string. This should be a quick fix in my opinion, however nothing seems to work that usually works in node, js, php or bash.. thanks in advance for any hints and ideas!

Environment:

Node-RED version: v0.15.2 | Node.js version: v5.12.0 | Mac OS X 10.11.6 = Darwin 15.6.0 x64 LE

Screenshots

This is the part of the flow:

This config works:

This config does not work:

Answer 1

After a good nights sleep the solution (at least what I thought at the time) was to adapt the exec node in node-red itself: The original code appended the additional arguments (the ones separated by whitespace) to the command, and then slice the whole string by whitespace into an array (node.cmd is the path to the command with or without whitespace):

before: var arg = node.cmd; arg += " "+msg.payload; arg = arg.match(/(?:[^\s"]+|"[^"]*")+/g);

and the (earlier, incomplete) solution was to prepend the command with the builtin array.unshift(<value>) function to the array after the slice operation, so that the command path with the whitespace is not affected by the array creation:

after: var arg = ""; ...add msg.payload and slice arg string into array.. arg.unshift(node.cmd);

The file can be found at: nodered node 75-exec.js on github, in the lines 46-51

Update to real solution:

After further investigation it was clear, that the Use spawn() instead of exec()? option was the problem: the command part with whitespace in double quotes and using exec() worked fine. And my approach couldn't be used when the command path contained an argument, e.g. in /home/foo bar/date -r 1000.

Following the issue at the official github repository of node-red the command part to the arguments array at the beginning after the slice but instead to have the command path with whitespace in quotes and later unwrapping them, copying the behaviour when exec() is used. He added this line in the original file after line 51: if (/^".*"$/.test(cmd)) { cmd = cmd.slice(1,-1); } and now both spawn() and exec() work the same - credits to him, unfortunately I don't know his username here.