Parsing Multi-Level JSON with PowerShell [duplicate] - json

Question

I have a json file, simplified version of it looks like this:
{
"Location": "EU",
"Country": {
"City": "xxx",
"Town": "xxx"
},
"Transport": {
"Train": "xxx"
}
}
I have run the ConvertFrom-Json command to convert to PSObject:
$conversion = Get-Content $path | ConvertFrom-Json
This will give me an output like this:
Location : EU
Country : #{City="xxx"; Town="xxx"}
Transport : #{Train="xxx"}
Question
How can I get the nested values to print out separately? I would want them all to print out like the "Location:EU" one
Is there a different command to ConvertFrom-Json that i should be using for this? Or do I just need to mess around with ConvertFrom-Json command a bit?
To note:
I am not just looking for a pretty print out - I would need them all separately for a script I am writing that will be looping through all the key/value pairs
I have read about the -Depth flag when using ConvertFrom-Json and does not seem to fix anything here - it seemed this was more relevant for ConvertTo-Json

Answer 1

In order to report all leaf properties as name-value pairs (i.e. those properties that contain primitive JSON values as opposed to containing nested objects with properties and / or arrays), you need to recursively walk the object graph:
Find helper function Get-LeafProperty below; assuming you have already defined it, you can call it as follows:
#'
{
"Location": "EU",
"Country": {
"City": "xxx",
"Town": "xxy"
},
"Transport": {
"Train": "xxz"
}
}
'# |
ConvertFrom-Json |
Get-LeafProperty
Output (the display formatting of [pscustomobject] instances with .Name and .Value properties representing all the leaf properties):
Name Value
---- -----
Location EU
City xxx
Town xxy
Train xxz
Get-LeafProperty source code:
# Walks a potentially nested [pscustomobject] graph
# as returned by ConvertFrom-Json and outputs all
# leaf properties as name-value custom objects.
function Get-LeafProperty {
param([Parameter(ValueFromPipeline)] [object] $InputObject)
process {
if ($InputObject -is [array]) { # array as single input object -> recurse
foreach ($o in $InputObject) { Get-LeafProperty $o }
}
else {
# Assumed to be a (potentially nested) [pscustomobject] instance:
# Recursively process its properties.
foreach ($p in $InputObject.psobject.properties) {
if ($p.Value -is [array]) { # array -> recurse
foreach ($o in $p.Value) { Get-LeafProperty $o }
} elseif ($p.Value -is [System.Management.Automation.PSCustomObject] ) { # nested [pscustomobject] -> recurse
Get-LeafProperty $p.Value
} else { # leaf property reached -> output name-value pair
[pscustomobject] #{ Name = $p.Name; Value = $p.Value }
}
}
}
}
}
Note: A variant of this function that outputs property name paths (e.g. Country.City) instead of just their names (e.g. City) can be found in this answer.