The following article describes how Upload API V2 can be used:
https://docs.stylelabs.com/en-us/contenthub/4.0.x/content/integrations/rest-api/upload/upload-api-v2.html.
 
Let’s demonstate the usage of API using Powershell 7. Uploading flow consists of three steps:

Request an upload

First, an asset needs to be created. It can be done using the following code:

$xAuthToken = "enter your auth token guid here"
$hostName = "https://YourCHHostname"

$fileName = "Test.png"
$filePath = "C:\TempDownloads\Test.png"
$fileSize = 792

# create request

$createAssetBody = @{
    file_name = $fileName
    file_size = $fileSize
    upload_configuration = @{
        name = "AssetUploadConfiguration"
    }
    action = @{
        name = "NewAsset"
    }
} | ConvertTo-Json

$createUrl = $hostName + "/api/v2.0/upload"

$createResponse = Invoke-WebRequest -Uri $createUrl -Method 'POST' -Body $createAssetBody -H @{"x-auth-token" = $xAuthToken; "Content-Type" = "application/json"}

 
In the response, we will get the following data:

  1. Response body has upload_identifier and file_identifier
{
  "upload_identifier": "uploadidentifier",
  "file_identifier": "fileidentifier"
}

 

  1. Location response Header contains the URL where we need to upload the data.

Perform the upload

For uploading the file, the approach described in this article is used: https://docs.microsoft.com/en-us/powershell/module/microsoft.powershell.utility/invoke-webrequest?view=powershell-7.2#example-5--submit-a-multipart-form-data-file

# upload request

$uploadUrl = $createResponse.Headers.Location[0]

$fileStream = [System.IO.FileStream]::new($filePath, [System.IO.FileMode]::Open)
$fileHeader = [System.Net.Http.Headers.ContentDispositionHeaderValue]::new('form-data')
$fileHeader.Name = $fileName
$fileHeader.FileName = Split-Path -leaf $filePath
$fileContent = [System.Net.Http.StreamContent]::new($fileStream)
$fileContent.Headers.ContentDisposition = $fileHeader
$fileContent.Headers.ContentType = [System.Net.Http.Headers.MediaTypeHeaderValue]::Parse("text/plain")

$multipartContent = [System.Net.Http.MultipartFormDataContent]::new()
$multipartContent.Add($fileContent)

Invoke-WebRequest -Body $multipartContent -Method 'POST' -Uri $uploadUrl -Headers @{"x-auth-token" = $xAuthToken}

$fileStream.Close()

Finalize the upload

To finalize the request, we need to post the response body received on the “Request an upload” step:

#finalize request

$finalizeUrl = $hostName + "/api/v2.0/upload/finalize"

Invoke-WebRequest -Uri $finalizeUrl -Method 'POST' -Body $createResponse.Content -H @{"x-auth-token" = $xAuthToken; "Content-Type" = "application/json"}

Full script

$xAuthToken = "enter your auth token guid here"
$hostName = "https://YourCHHostname"

$fileName = "Test.png"
$filePath = "C:\TempDownloads\Test.png"
$fileSize = 792

# create request

$createAssetBody = @{
    file_name = $fileName
    file_size = $fileSize
    upload_configuration = @{
        name = "AssetUploadConfiguration"
    }
    action = @{
        name = "NewAsset"
    }
} | ConvertTo-Json

$createUrl = $hostName + "/api/v2.0/upload"

$createResponse = Invoke-WebRequest -Uri $createUrl -Method 'POST' -Body $createAssetBody -H @{"x-auth-token" = $xAuthToken; "Content-Type" = "application/json"}

# upload request

$uploadUrl = $createResponse.Headers.Location[0]

$fileStream = [System.IO.FileStream]::new($filePath, [System.IO.FileMode]::Open)
$fileHeader = [System.Net.Http.Headers.ContentDispositionHeaderValue]::new('form-data')
$fileHeader.Name = $fileName
$fileHeader.FileName = Split-Path -leaf $filePath
$fileContent = [System.Net.Http.StreamContent]::new($fileStream)
$fileContent.Headers.ContentDisposition = $fileHeader
$fileContent.Headers.ContentType = [System.Net.Http.Headers.MediaTypeHeaderValue]::Parse("text/plain")

$multipartContent = [System.Net.Http.MultipartFormDataContent]::new()
$multipartContent.Add($fileContent)

Invoke-WebRequest -Body $multipartContent -Method 'POST' -Uri $uploadUrl -Headers @{"x-auth-token" = $xAuthToken}

$fileStream.Close()

#finalize request

$finalizeUrl = $hostName + "/api/v2.0/upload/finalize"

Invoke-WebRequest -Uri $finalizeUrl -Method 'POST' -Body $createResponse.Content -H @{"x-auth-token" = $xAuthToken; "Content-Type" = "application/json"}