NCPA Powershell Plugin trouble passing arguments

[rfaulkner99]

I am having trouble passing parameters using a custom powershell plugin from a Windows machine running the NCPA 3.0.0.client.

To help with testing, I wrote the following PS script:
param (
[string]$F='John',
[string]$L='Doe',
[string]$M='E'
)

write-host "Success! $($F) $($M) modified $($L)."
Exit 0

Then, I try passing parameters, initially with Powershell named parameters like -F Joe -L Donuts, but that didn't work at all. Eventually I settled on using positional parameters, but have had issues getting that to work as well.

To test, I am modifying the nrdp.cfg on the Windows machine, restarting the service and then going to http://localhost:5693/gui/checks.

I have tried lots of combinations with varying results. For example:
%HOSTNAME%|TestArgs = plugins/testargs.ps1 --args Joe Donuts S"
returns Joe E Doe

Here are some of my notes, sorry they are a little disorganized. Keep in mind F used to be First, M - Middle, L - Last
-a did not work
--args 'G K B' not working at all
--args 'G,K,B' treats as first argument only
--args '-First G' not working
--args '--First G' not working
--args "-First G" not working
--args "-First 'G'"
--args -First G - specify a system string
--args -First "G" - Same
--args -First 'G' - Same
--args 'G','k' recognized first two params, but included quotes
--args Gar,k combined into 1 parameter.
--args "Gar ak","k" not working at all - Same with single quotes - doesn't seem to like spaces.
Gar,F,Eild - combined
"Gar","F","Eild" - correclty set first to "Gar" but combimed "F","Eild" together for last
"Gar,F,Eild" - combined into first

[bbahn]

Hello @rfaulkner99,

For your PowerShell script to process the arguments correctly, you want the CLI input to be

Code: Select all

plugins/plugin.ps1 "arg1" "arg2" "arg3"

To get this behavior as a passive check, you can use

Code: Select all

%HOSTNAME%|TEST = plugins/test.ps1 --args "arg1" --args "arg2" --args "arg3"

You can more intuitively figure out how to properly configure your plugin inputs by first going through the NCPA UI at https://your_NCPA_ip_address:5693/gui/api/ and selecting plugins and pluginname.ps1 and then entering your arguments into the argument box and adding arguments as necessary until you get your desired result.

[rfaulkner99]

Thanks! That got me further, and the API tip makes testing much easier.

The only thing I am stuck on now is getting it to pass a path with a space. Powershell expects it to be wrapped in quotes, but I have tried double-quoting and using \ as an escape character and neither work.

[bbahn]

That is a bug that should be fixed in NCPA 3.1.0.

[rfaulkner99]

OK, thanks for the information. Also, passing multiple arguments in a passive check using:

Code: Select all

%HOSTNAME%|TEST = plugins/test.ps1 --args "arg1" --args "arg2" --args "arg3"

did not work for me either. When I do that, it only passes the last argument (arg3).

Is that also a bug?

[bbahn]

This will work correctly in NCPA 3.1.0, which is scheduled to release very soon.

[rfaulkner99]

Almost everything seems to be working now with 3.1 except passing double quotes to arguments. I need to pass double quotes to a powershell -path argument - the path has a space and powershell requires it to be wrapped in double quotes - when I pass the argument it passes it with escape characters as show below. This is using the local API in the web gui.

Code: Select all

powershell -ExecutionPolicy Bypass -File C:\\Program Files\\Nagios\\NCPA\\plugins\\check_release_args.ps1 -path '\"F:\\My Folder\\Backup\\Logs\\Release\"' -maxage 24 -filter *.*

Please let me know if there is another way to pass double quotes to the command line argument.

[jmichaelson]

Where did you get the check_release_args script from? is it possible to modify it to handle the escaped quote? As a workaround, it may be possible to use the legacy 8.3 file name (as shown by doing a dir /X in a command prompt) for the directory and bypass the quotes, until we can come up with a better solution.

[rfaulkner99]

I wrote the script. I just tried adding some code to mitigate the issue, but it is not working. Here is the code I added, which works from powershell if I feed it a similar looking escaped path. I commented above the line that I added

Code: Select all

$path = '\"F:\\Special Apps\\Backup\\Logs\\Release\"'
#below is the line I added
$path=($path -replace '\\"','')
$filter="*.*"
If ($Path -like '*\') {$LogFilePath = $Path + $Filter}
Else {$LogFilePath = $Path + "\" + $Filter}
$Files=gci $logfilepath

And here is the error I get when running from the web API.

Code: Select all

{
    "returncode": 2,
    "stdout": "\"F:\\Special Apps\\Backup\\Logs\\Release\"\n\"F:\\Special Apps\\Backup\\Logs\\Release\"\ngci : Cannot find drive. A drive with the name '\"F' does not exist.\nAt C:\\Program Files\\Nagios\\NCPA\\plugins\\check_release_args.ps1:17 char:8\n+ $Files=gci $logfilepath\n+        ~~~~~~~~~~~~~~~~\n    + CategoryInfo          : ObjectNotFound: (\"F:String) [Get-ChildItem], Dri \n   veNotFoundException\n    + FullyQualifiedErrorId : DriveNotFound,Microsoft.PowerShell.Commands.GetC \n   hildItemCommand\n \ngci : Cannot find drive. A drive with the name '\"F' does not exist.\nAt C:\\Program Files\\Nagios\\NCPA\\plugins\\check_release_args.ps1:19 char:11\n+ $LastFile=gci $logfilepath| sort lastwritetime | select -last 1\n+           ~~~~~~~~~~~~~~~~\n    + CategoryInfo          : ObjectNotFound: (\"F:String) [Get-ChildItem], Dri \n   veNotFoundException\n    + FullyQualifiedErrorId : DriveNotFound,Microsoft.PowerShell.Commands.GetC \n   hildItemCommand\n \nError! 0 files considered, no files match *.*.",
    "cmd": "powershell -ExecutionPolicy Bypass -File C:\\Program Files\\Nagios\\NCPA\\plugins\\check_release_args.ps1 \"F:\\Special Apps\\Backup\\Logs\\Release\""
}

[bbahn]

@rfaulkner, it seems your issue is that your wrapping of the path in quotes is breaking your plugin.

I see a few methods to handle this:

1. Use single quotes
2. Have your script convert the escaped double quotes to unescaped double quotes (($path -replace '\"', '"'))