Powershell - Where-Clause multiple JSON Array key - arrays

Question

I cannot find any solution why my where-clause in my powershell do not give me the output I would expect.
I have a JSON File looks like this:
[
{
"name": "server1",
"tag": ["App", "Mid-Tier", "User"],
"domain": "domainname",
"alias": ["Alias3"],
"ip": null,
"tcp": 8080,
"active": false,
"apps": ["ARS", "Tomcat"],
"patch": null,
"hotfix": null
},
{
"name": "server2",
"tag": ["Reporting"],
"domain": "domainname",
"alias": ["Alias3"],
"ip": null,
"tcp": 8080,
"active": false,
"apps": ["ARS", "Tomcat"],
"patch": null,
"hotfix": null
},
{
"name": "server3",
"tag": ["DB"],
"domain": "domainname",
"alias": ["Alias1", "Alias2", "Alias3", "Alias4"],
"ip": null,
"tcp": 8080,
"active": true,
"apps": ["SQL"],
"patch": null,
"hotfix": null
},
{
"name": "server5",
"tag": ["Reporting"],
"domain": "domainname",
"alias": ["Alias1"],
"ip": null,
"tcp": 8080,
"active": false,
"apps": ["ARS", "Tomcat"],
"patch": null,
"hotfix": null
}
]
EDIT/UPDATE
Ok I have to give you more details what I am trying to accomplish/understand:
I have 3 Files:
- a JSON File with data like above
- a script storing all functions and variables
- a main script
This is how my function looks like:
function opl_GetHostList {
[CmdletBinding()]
param (
[parameter (
mandatory=$false,
HelpMessage = "Enter alias name.")]
[string[]]
$Aliasname,
[parameter (
mandatory=$false,
HelpMessage = "Enter tag name.")]
[string[]]
$Tagname,
[parameter (
mandatory=$false,
HelpMessage = "Enter app name.")]
[string[]]
$Appname,
[parameter (
mandatory=$false,
HelpMessage = "Enter Active State: Either false or true. Default = true")]
[bool]
$Active = $true,
[parameter (
mandatory=$false,
HelpMessage = "Choose selection Object.")]
[string[]]
$Select
)
$WhereArray = #()
# evaluate these with contains comparison
if ($Aliasname) {$WhereArray += '$Aliasname -contains $_.alias'}
#if ($Tagname) {$WhereArray += '$Tagname -contains $_.tag'}
#if ($Appname) {$WhereArray += '$Appname -contains $_.apps'}
# Build the where array into a string by joining each statement with -and
$WhereString = $WhereArray -Join " -and "
# Create the scriptblock with your final string
$WhereBlock = [scriptblock]::Create($WhereString)
$opl_Hostlist | Where-Object {($WhereBlock.invoke()) -and $Active -eq $_.active} | Select-Object $Select
}
so now comes the part I don't understand.
If I use following in the main.ps1:
$opl_Hostlist | Where-Object {$_.alias -contains "alias3"} | Select-Object name
OUTPUT:
name
----
server1
server2
server3
BUT, if I use it with my function:
opl_GetHostList -Aliasname alias3 -Select name
I get this OUTPUT:
name
----
server1
server2
So why do I not get the "server3" with my second method when I am calling the data with my function?
Very thankfull for any help.

Answer 1

According to the JSON you have posted, you will get ConvertFrom-Json : Invalid array passed in, extra trailing ','. (1018) error. This is because of the unwanted comma after the last item.
And I would suggest to use -in instead of -match operation as Alias property is a list. In your comparison, left operand is a single element and right operand is a list, hence you have to use -in, otherwise -contains.
if ($Aliasname) {
$Aliasname | ForEach-Object{ $WhereArray += "$_ -in `$_.alias"}
}
$WhereArray -Join '-or'