Running executable with command line parameters in PowerShell - powershell

Question

This has to be possible. I am able to open a command prompt in windows and do the following:
<some exe> <some exe command line parameters>
There must be an equivalent way to do this in PowerShell or even a standard windows batch file. For example, from the windows command prompt I can start a docker container with:
docker run –-net=kafka -d –-name=zookeeper -e ZOOKEEPER_CLIENT_PORT=2181 confluentinc/cp-zookeeper:4.1.0
however if I try something like this with PowerShell
& "docker" run –-net=kafka -d –-name=zookeeper -e ZOOKEEPER_CLIENT_PORT=2181 confluentinc/cp-zookeeper:4.1.0
it fails with an generic error:
invalid reference format.
Perhaps PowerShell is not suited for this type of advanced use case. Any suggestions would be appreciated!
Is there a better scripting language for advanced usages like this?

Answer 1

I think Start-Process cmdlet will be useful. ArgumentList can be single or double quoted.
Start-Process docker -ArgumentList "run –-net=kafka -d –-name=zookeeper -e ZOOKEEPER_CLIENT_PORT=2181 confluentinc/cp-zookeeper:4.1.0"

Answer 2

By and large, external programs in PowerShell are called the same way as from cmd.exe - there are differences, due to PowerShell having additional metacharacters such as $ and #, but they do not come into play in your specific case.
(Your & "docker" ... variant would work in principle too, but the use of & is only necessary if you must use a quoted or variable-based command name or path).
The problem is that your original command line contains two instances of – (EN DASH, U+2013) instead of the expected ASCII-range - dash (hyphen), which docker doesn't recognize.
A quick way to discover the problem:
# Print the code points of characters outside the ASCII range.
PS> [int[]] [char[]] '& "docker" run –-net=kafka -d –-name=zookeeper -e ZOOKEEPER_CLIENT_PORT=2181 confluentinc/cp-zookeeper:4.1.0' -gt 127
8211
8211
Decimal 8211 is hex. 0x2013, the code point of en-dash, whereas the code point of the regular - is 45 (0x2d).
All that is needed is to replace these – instances with - (and, since docker needn't be quoted, there is no need for &):
docker run --net=kafka -d --name=zookeeper -e ZOOKEEPER_CLIENT_PORT=2181 confluentinc/cp-zookeeper:4.1.0
Your own answer shows a variable-based implementation of the command that is effectively the same as the command above - if all the arguments are known in advance, there is never a need to use variables.
If you do want to use variables, it is much simpler to use a single array variable for all the arguments and pass that:
$dockerExe = 'docker'
$dockerArgs = 'run',
'--net=kafka',
'-d',
'--name=zookeeper',
'-e',
'ZOOKEEPER_CLIENT_PORT=2181',
'confluentinc/cp-zookeeper:4.1.0'
& $dockerExe $dockerArgs
Note:
The executable name/path must always be specified separately, and if it is quoted or involves variable references (as in this case), &, the call operator must be used for invocation, for syntactic reasons.
Passing the arguments as an array this way works with external programs; for PowerShell commands, you'd create a hashtable variable that you pass with sigil # instead of $, a feature known as splatting.

Answer 3

There is a lot of complexities in powershell escaping. I wrote this module to assist with running of external commands:
https://github.com/choovick/ps-invoke-externalcommand
Demo:
https://terminalizer.com/view/49acb54a979
Install-Module -Name ExternalCommand -Scope CurrentUser
Invoke-ExternalCommand -Command "docker" -Arguments #("run","-d","--name=zookeeper","--net=kafka","-e","ZOOKEEPER_CLIENT_PORT=2181", "confluentinc/cp-zookeeper:4.1.0")

Answer 4

Here's how to do it.
$app = 'docker'
$a1 = 'run'
$a2 = '--net=kafka'
$a3 = '-d'
$a4 = '--name=zookeeper'
$a5 = '-e'
$a6 = 'ZOOKEEPER_CLIENT_PORT=2181'
$a7 = 'confluentinc/cp-zookeeper:4.1.0'
& $app $a1 $a2 $a3 $a4 $a5 $a6 $a7