Powershell Invoke-WebRequest returns array of objects but processes as if there is only 1

Question

$path = "https://api.statuspage.io/v1/pages/$page_id/$endpoint"
$req  = Invoke-WebRequest -Uri $path -Method GET

This request returns an array of objects (50+). I can see this by running a Write-Host $req

Problem is, when I try something like

foreach($i in $req) {
  Write-Host $i
}

I am given the entire object. And similarly, if I run Write-Host $req.length I am given 1. What gives?

Additionally, there is no way to run something like

$global:res = ConvertFrom-Json $req

Because it's already being returned as a JSON

what do you get from `$Req.GetType()` or from `$Req | Get-Member`? — Lee_Dailey, Nov 13 '20 at 14:45
GetType() gives me `Microsoft.PowerShell.Commands.HtmlWebResponseObject` and `Get-Member` gives me a bynch of stuff `void...bool..int..type.. etc` — vin_Bin87, Nov 13 '20 at 14:49
What if you run `$singleReq = $req | select-object -first 1; $singleReq.GetType()` ? That is a quick way to convert an array response to get the first item (or same item if not an array). Also, it's possible that powershell is following links...try using `-UseBasicParsing` to keep it from parsing HTML — Luke, Nov 13 '20 at 15:15
It gives me this: `Microsoft.PowerShell.Commands.HtmlWebResponseObject` — vin_Bin87, Nov 13 '20 at 15:19
@vin_Bin87 - i see that `Theo` pointed out how to deal with your actual objects. kool! glad to know that you got it working as needed ... [*grin*] — Lee_Dailey, Nov 13 '20 at 16:12

mklement0 · Accepted Answer · 2020-11-13T16:31:10.960

If your intent is to parse the JSON text into (nested) objects ([pscustomobject] graphs) anyway, you can simply use Invoke-RestMethod rather than Invoke-WebRequest, because Invoke-RestMethod has ConvertFrom-Json built in, in a manner of speaking:

$path = "https://api.statuspage.io/v1/pages/$page_id/$endpoint"

# Retrieves JSON *and* parses it into objects.
$result = Invoke-RestMethod -Uri $path -Method GET

As for what you tried:

$req = Invoke-WebRequest ...

Invoke-WebRequest returns a single object, namely and instance of BasicHtmlWebResponseObject (PowerShell [Core] v6+) / HtmlWebResponseObject (Windows PowerShell), which is a wrapper object with metadata that stores the content of the response received in the .Content property.

In your case, .Content contains JSON as a single string, which ConvertFrom-Json can parse into a nested object(s).

To parse this JSON string into one or more (potentially nested) objects ([pscustomobject] graphs):

$result = ConvertFrom-Json $req.Content

Note that even $result = ConvertFrom-Json $req would work, because when a response object is implicitly stringified, it interpolates to the value of its .Content property.

As Theo points out in a comment, you can also use the pipeline:

$result = $req | ConvertFrom-Json

Powershell Invoke-WebRequest returns array of objects but processes as if there is only 1

1 Answers1