Powershell sort PSObject alphabetically - json

Question

Given a custom powershell object (bar) that is created from json (foo.json)
How would you sort the object alphabetically by key?
foo.json
{
"bbb": {"zebras": "fast"},
"ccc": {},
"aaa": {"apples": "good"}
}
Desired output
foo.json
{
"aaa": {"apples": "good"},
"bbb": {"zebras": "fast"},
"ccc": {}
}
Example
$bar = get-content -raw foo.json | ConvertFrom-Json
$bar.gettype()
IsPublic IsSerial Name BaseType
-------- -------- ---- --------
True False PSCustomObject System.Object
I've tried the following using sort-object
$bar = $bar | Sort
$bar = $bar | Sort-Object
Sort-Object -InputObject $bar
Sort-Object -InputObject $bar -Property Name
Sort-Object -InputObject $bar -Property #{Expression="Name"}
Sort-Object -InputObject $bar -Property #{Expression={$_.PSObject.Properties.Name}}
I've also tried converting the PSObject to a hashtable (hashtables appear to automatically sort based on name), then convert that hashtable back to json, but it looses the order again.
$buzz = #{}
$bar.psobject.properties |Foreach { $buzz[$_.Name] = $_.Value }
ConvertTo-Json $buzz -Depth 9
Update
Changed foo.json to include values aswell as keys

Answer 1

As Mathias R. Jessen notes, there is no collection to sort here, just a single object whose properties you want to sort, so you need reflection via Get-Member to obtain the object's properties:
$bar = get-content -raw foo.json | ConvertFrom-Json
# Build an ordered hashtable of the property-value pairs.
$sortedProps = [ordered] #{}
Get-Member -Type NoteProperty -InputObject $bar | Sort-Object Name |
% { $sortedProps[$_.Name] = $bar.$($_.Name) }
# Create a new object that receives the sorted properties.
$barWithSortedProperties = New-Object PSCustomObject
Add-Member -InputObject $barWithSortedProperties -NotePropertyMembers $sortedProps
A more streamlined version that uses -pv (-PipelineVariable) to "cache" the unsorted custom object produced by ConvertFrom-Json:
$barSortedProps = New-Object PSCustomObject
Get-Content -Raw foo.json | ConvertFrom-Json -pv jo |
Get-Member -Type NoteProperty | Sort-Object Name | % {
Add-Member -InputObject $barSortedProps -Type NoteProperty `
-Name $_.Name -Value $jo.$($_.Name)
}

Answer 2

what about this:
Function Sort-PSObject {
[CmdletBinding()]
Param(
[Parameter(ValueFromPipeline=$true)]$inputString
)
process {
($inputString | out-string).trim() -split "`r`n" | sort
}
}
Can send direct from pipeline

Answer 3

A combined version of #mklement0 and #EricWeintraub's answers:
Function Sort-PSObjectMembers {
[CmdletBinding()]
Param(
[Parameter(ValueFromPipeline=$true)]$inputObj
)
process {
$sortedProps = [ordered] #{}
Get-Member -Type NoteProperty -InputObject $inputObj | Sort-Object Name | ForEach-Object { $sortedProps[$_.Name] = $inputObj.$($_.Name) }
# Create a new object that receives the sorted properties.
$sortedObj = New-Object PSCustomObject
Add-Member -InputObject $sortedObj -NotePropertyMembers $sortedProps
return $sortedObj
}
}
So you can use it like this:
$elements | Sort-PSObjectMembers | ConvertTo-Json -Depth 32 | Out-File "elements.json" -Encoding utf8