(Chilkat2-Python) Sign JSON to Create CAdES P7S Bytes

Demonstrates how to sign JSON using a certificate + private key from a .p12/.pfx to create a CAdES P7S byte array.

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import sys
import chilkat2

# This example assumes the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

crypt = chilkat2.Crypt2()

cert = chilkat2.Cert()
success = cert.LoadPfxFile("qa_data/pfx/cert_test123.pfx","test123")
if (success != True):
    print(cert.LastErrorText)
    sys.exit()

# Tell the crypt component to use this cert.
success = crypt.SetSigningCert(cert)
if (success != True):
    print(crypt.LastErrorText)
    sys.exit()

# The CadesEnabled property applies to all methods that create PKCS7 signatures. 
# To create a CAdES-BES signature, set this property equal to true. 
crypt.CadesEnabled = True

crypt.HashAlgorithm = "sha256"

jsonSigningAttrs = chilkat2.JsonObject()
jsonSigningAttrs.UpdateInt("contentType",1)
jsonSigningAttrs.UpdateInt("signingTime",1)
jsonSigningAttrs.UpdateInt("messageDigest",1)
jsonSigningAttrs.UpdateInt("signingCertificateV2",1)
crypt.SigningAttributes = jsonSigningAttrs.Emit()

# By default, all the certs in the chain of authentication are included in the signature.
# If desired, we can choose to only include the signing certificate:
crypt.IncludeCertChain = False

# Create the CAdES-BES attached signature, which contains the original data.
crypt.Charset = "utf-8"

# cadesP7s is a memoryview
cadesP7s = crypt.OpaqueSignString("{ \"abc\": 123}")
if (crypt.LastMethodSuccess == False):
    print(crypt.LastErrorText)
    sys.exit()

# Verify the signature and extract the original JSON:
originalJson = crypt.OpaqueVerifyString(cadesP7s)
if (crypt.LastMethodSuccess == False):
    print(crypt.LastErrorText)
    sys.exit()

print("Original JSON: " + originalJson)

print("Success!")