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Get a JWS Protected Header

See more JSON Web Signatures (JWS) Examples

Demonstrates Jws.GetProtectedH, which copies the decoded protected header of a signature into a JsonObject.

Background. The protected header is integrity-protected by the signature. Inspecting it (for example the alg value) is useful before deciding how to validate.

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Add-Type -Path "C:\chilkat\ChilkatDotNet47-x64\ChilkatDotNet47.dll"

$success = $false

$jws = New-Object Chilkat.Jws

#  Load the JWS compact serialization.
$jwsCompact = "eyJhbGciOiJIUzI1NiJ9.VGhpcyBpcyB0aGUgY29udGVudCB0byBzaWduLg.<signature>"
$success = $jws.LoadJws($jwsCompact)
if ($success -eq $false) {
    $($jws.LastErrorText)
    exit
}

#  Copy the decoded protected header of signature 0 into a JsonObject.
$json = New-Object Chilkat.JsonObject
$success = $jws.GetProtectedH(0,$json)
if ($success -eq $false) {
    $($jws.LastErrorText)
    exit
}

$json.EmitCompact = $false
$($json.Emit())