Parsing through PowerShell API Response - json

Question

I build a C# project which called an API and received a response as shown below and I looped through to determine how many times the System.State "New Value" was Resolved. We want to move this to run on a schedule via a pipeline so I am attempting to translate this into PowerShell.
I'm unfamiliar with how to create objects and loop through them in PowerShell as I'v shown in my C# project. Any guidance would be appreciated.
I've tried Invoke-RestMethod with | ConvertFrom-JSON:
$HistoryQueryResult = Invoke-RestMethod -Method Get -ContentType application/json -Uri $QueryUri -Headers $header | ConvertFrom-Json
..but, I'm unsure after this point.
var RootObjects = JsonConvert.DeserializeObject<WorkItemHistoryJson.Root>(result2);
foreach (var item in RootObjects.value)
{
if (item.fields != null)
{
if (item.fields.SystemState != null)
{
if (item.fields.SystemState.newValue == StateToCheck)
{
TES_WorkItem.CountOfTestingRounds += 1;
}
}
}
}
{
"count": 6,
"value": [
{
"id": 1,
"workItemId": 226,
"rev": 1,
"revisedBy": {
"id": "0e7735b9-cf6a-6468-82c1-81e6b092addd",
"descriptor": "aad.MGU3NzM1YjktY2Y2YS03NDY4LTgyYzEtODFlNmIwOTJhZGRk"
},
"revisedDate": "2020-05-22T09:49:00.81Z",
"fields": {
"System.Id": {
"newValue": 226
},
"System.Reason": {
"newValue": "New"
},
"System.CreatedDate": {
"newValue": "2020-05-22T07:59:22.64Z"
},
"System.ChangedDate": {
"newValue": "2020-05-22T07:59:22.64Z"
}
}
},
{
"id": 2,
"workItemId": 226,
"rev": 2,
"revisedDate": "2020-05-22T09:49:04.45Z",
"fields": {
"System.Rev": {
"oldValue": 1,
"newValue": 2
},
"System.State":{
"oldValue":"New",
"newValue":"Resolved"
}
}
}
]
}

Answer 1

I believe, assuming the JSON follows this exact structure, you could do it just like this, which returns 1 when testing with the one posted in question:
$json = Invoke-RestMethod -Method Get -ContentType application/json -Uri $QueryUri -Headers $header
(#($json.value.fields.'system.state'.newValue) -eq 'Resolved').Count
-eq can be used for filtering if the LHS of the comparison is an array, hence the use of the array sub-expression #(..).