Serialize REST response in powershell

Question

I'm connecting to a REST service

$response = Invoke-RestMethod -Uri $URL -Headers $headers -Method POST -Body $body_json -ContentType "application/json" 
$response.Outputs

and I get a response in that format

    Actual: {
        "2017-08-29T14:37:47.137",
        "2017-08-30T13:07:09.563",
        "2017-08-30T14:41:29.023"
    },
    Start: {
        "2017-08-29T14:36:12.42",
        "2017-08-30T12:59:53.05",
        "2017-08-30T14:40:45.34"
    },
    NumScrapsList: {
        0,
        3,
        ...
        

but I would like to have it in that form

    {   
        "NumScrapsList":0,
        "Actual":"2017-08-29T14:37:47.137",
        "Start":"08-29T14:36:12.42"
    },
    {
        "NumScrapsList":3,
        "Actual":"2017-08-30T13:07:09.563",
        "Start":"2017-08-30T12:59:53.05"
    }

In a pythonic approach I can do it like so (including "outputs" key):

outputs = [dict(zip(resp['Outputs'].keys(), e))
           for e in zip(*resp['Outputs'].values())]

pprint(outputs)

but in powershell I cannot know how to do it. Could you put me in the right direction?

EDIT with the full $response.outputs from Invoke-RestMethod

the $response.outputs is

Type         : {a, b, c}
Code        : {xxx, yyy, eee}
CompletionDate : {1900-01-01T00:00:00, 1900-01-01T00:00:00, 1900-01-01T00:00:00}
OrderQuantity        : {30, 30, 3}
NumScraps            : {0, 0, 0}
ActualDate      : {2021-11-16T15:17:00, 2021-11-16T15:18:00, 1900-01-01T00:00:00}
Status               : {WT, FD, RT}
Order           : {70000, 30794, 94098}
Sequence        : {0300, 0400, 0500}

Then I can convertto-json and the output is:

{
    "Type":  [
                         "a",
                         "b",
                         "c"
                     ],
    "Code":  [
                          "xxx",
                          "yyy",
                          "eee"
                      ],
    "CompletionDate":  [
                                 "1900-01-01T00:00:00",
                                 "1900-01-01T00:00:00",
                                 "1900-01-01T00:00:00"
                             ],
    "OrderQuantity":  [
                          30,
                          30,
                          3
                      ],
    "NumScraps":  [
                      0,
                      0,
                      0
                  ],
    "ActualDate":  [
                            "2021-11-16T15:17:00",
                            "2021-11-16T15:18:00",
                            "1900-01-01T00:00:00"
                        ],
    "Status":  [
                   "WT",
                   "FD",
                   "RT"
               ],
    "Order":  [
                       "70000",
                       "30794",
                       "94098"
                   ],
    "Sequence":  [
                          "0300",
                          "0400",
                          "0500"
                      ]
}

that said the waitingforguacamole solution works even if is a bit tricky (and thanks, sure, for your help!)

Answer 1

OK, I took a shot at this, perhaps inelegantly (it's neither functional nor Pythonic), and I'm sure others will have far more expressive methods of doing this, but this could be a start:

I cleaned up the JSON to look like this

{
    "Actual": [
        "2017-08-29T14:37:47.137",
        "2017-08-30T13:07:09.563",
        "2017-08-30T14:41:29.023"
    ],
    "Start": [
        "2017-08-29T14:36:12.42",
        "2017-08-30T12:59:53.05",
        "2017-08-30T14:40:45.34"
    ],
    "NumScrapsList": [
        0,
        3,
        7
    ]
}

(I added a value to NumScrapsList for completeness, and turned each top-level JSON field into an array)

Then,

#simulate your REST method call result
$json = "{
    `"Actual`": [
        `"2017-08-29T14:37:47.137`",
        `"2017-08-30T13:07:09.563`",
        `"2017-08-30T14:41:29.023`"
    ],
    `"Start`": [
        `"2017-08-29T14:36:12.42`",
        `"2017-08-30T12:59:53.05`",
        `"2017-08-30T14:40:45.34`"
    ],
    `"NumScrapsList`": [
        0,
        3,
        7
    ]
}"

#create a field map
$fieldMap = @("NumScrapsList", "Start", "Actual")

#convert the JSON to a Powershell object, create an empty array
$in = $json | ConvertFrom-JSON

#using NumScrapsList as your iterator
0..($in.NumScrapsList.Count-1) | ForEach-Object {
    $fieldMap | ForEach-Object -Begin {
        #reference the outer loop index
        $index = $_
        #initialize an accumulator for the object whose properties to be mapped
        $obj = @{}
    } -Process {
        #in order of fieldMap's properties, grab those fields from the input
        #and add them to the accumulator by name
        $obj."$_" = $in."$_"[$index]
    } -End {
        #return that accumulator
        $obj
    }
} | ConvertTo-Json

and that processing block can be reduced to:

$fieldMap = @("NumScrapsList", "Start", "Actual"); 
$in = $json | ConvertFrom-JSON
0..($in.NumScrapsList.Count-1) | ForEach-Object { 
    $fieldMap | ForEach-Object { $index = $_; $obj = @{} } {
        $obj."$_" = $in."$_"[$index]
    } { $obj }
} | ConvertTo-Json