Powershell Invoke-Webrequest w/ JSON Body - Can not deserialize...?

Question

I need to perform an Invoke-Webrequest with a specifically formatted body to add devices to a product. Here is what it looks like in json (example straight from the vendor's documentation):

$body_json = '{"datasource": [{
            "parentId": "123456789000",
            "name": "(name)",
            "id": "(value)",
            "typeId": 0,
            "childEnabled": false,
            "childCount": 0,
            "childType": 0,
            "ipAddress": "(ipAddress)",
            "zoneId": 0,
            "url": "(url)",
            "enabled": false,
            "idmId": 123456789000,
            "parameters": [{
                "key": "(key)",
                "value": "(value)"
            }]
        }]}'

When I try to submit this in its json representation though, I get the following error:

Invoke-WebRequest : Can not deserialize instance of com.vendor.etc.DataSourceDetail out of START_ARRAY token at [Source: java.io.StringReader@22c614; line: 1, column: 1] At C:\powershell_script_location\ps.ps1:114 char 9 + $request = Invoke-WebRequest $url -Method Post -Headers $headers -Body $body_json - ... +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + CategoryInfo : InvalidOperation: (System.Net.HttpWebRequest:HttpWebRequest) [Invoke-WebRequest], WebException + FullyQualifiedErrorId : WebCmdletWebResponseException,Microsoft.PowerShell.Commands.InvokeWebRequestCommand

The issue is with the format of the "parameters", parameter because the request submits fine when omitting the "parameters", but then the devices that I'm adding are missing important parameter details.

Is there something wrong with Invoke-WebRequest, JavaScriptSerializer, the vendor's code, or is this a user error? Let me know if any clarification is needed.

Unfortunately I don't know what a com.vendor.etc.DataSourceDetail instance looks like, as I am using an API and I don't have access to it directly.

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pfx pfx · Accepted Answer · 2018-06-01T21:16:42

Use Invoke-RestMethod instead of Invoke-WebRequest.

If you have the body as a string use:

Invoke-RestMethod -Uri http://your-url.com -Method POST -Body $body_json -ContentType "application/json"

If the body must be constructed from data/parameters, it might be easier to build a hashtable and convert it to json via ConvertTo-Json:

$body_json = @{
    datasource = @(
        @{
            parentId = 123456789000
            name = "name"
            id = "value"
            typeId = 0
            childEnabled = $false
            childCount = 0
            childType = 0
            ipAddress = "ipAddress"
            zoneId = 0
            url = "url"
            enabled = $false
            idmId = 123456789000
            parameters = @( @{
                key = "key"
                value = "value"
            })
       })} | ConvertTo-Json -Depth 4

Invoke-RestMethod -Method 'Post' -Uri http://your-url.com -Body $body_json -ContentType "application/json"

Powershell Invoke-Webrequest w/ JSON Body - Can not deserialize...?

2 Answers