CkPython Requires Chilkat v11.0.0+

Verify a JWT Created by the Amazon Cognito Service

See more JSON Web Token (JWT) Examples

Demonstrates how to verify a JWT created by the Amazon Cognito Service. CkPython

import sys
import chilkat

success = False

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

#  The public keys for this example are at https://cognito-idp.us-east-2.amazonaws.com/us-east-2_******/.well-known/jwks.json
#  Let's get them:

http = chilkat.CkHttp()
sbJsonKeys = chilkat.CkStringBuilder()
success = http.QuickGetSb("https://cognito-idp.us-east-2.amazonaws.com/us-east-2_******/.well-known/jwks.json",sbJsonKeys)
if (success == False):
    print(http.lastErrorText())
    sys.exit()

jsonKeys = chilkat.CkJsonObject()
jsonKeys.LoadSb(sbJsonKeys)
jsonKeys.put_EmitCompact(False)
print(jsonKeys.emit())

#  Here are the keys:

#  {
#    "keys": [
#      {
#        "alg": "RS256",
#        "e": "AQAB",
#        "kid": "1A/L5Fsb2EsEwxy5E0cmCMS1BnMe6Jl6NXiMig4iNwU=",
#        "kty": "RSA",
#        "n": "y0w7BJrIJYi ... jKG27z2P3OKw",
#        "use": "sig"
#      },
#      {
#        "alg": "RS256",
#        "e": "AQAB",
#        "kid": "mos6VTJnvDwurY3ghJg6IAPUq+dMwl6CL/iThzJOkzg=",
#        "kty": "RSA",
#        "n": "qbIEH-7tg6yrT ... 3Fj94ooTd0w",
#        "use": "sig"
#      }
#    ]
#  }

#  Try the 1st key.
jsonKey1 = chilkat.CkJsonObject()
jsonKeys.ObjectOf2("keys[0]",jsonKey1)

pubKey1 = chilkat.CkPublicKey()
success = pubKey1.LoadFromString(jsonKey1.emit())
if (success == False):
    print(pubKey1.lastErrorText())
    sys.exit()

print("Success")

jwt = chilkat.CkJwt()

#  I did not include the an actual AWS Cognito token here because our test sample used customer-provided data..
token = "eyJ..asXg"

#  First verify the signature.
sigVerified = jwt.VerifyJwtPk(token,pubKey1)
print("verified: " + str(sigVerified))

#  Let's see if the time constraints, if any, are valid.
#  The above JWT was created on the afternoon of 16-May-2016, with an expiration of 1 hour.
#  If the current system time is before the "nbf" time, or after the "exp" time,
#  then IsTimeValid will return false/0.
#  Also, we'll allow a leeway of 60 seconds to account for any clock skew.
#  Note: If the token has no "nbf" or "exp" claim fields, then IsTimeValid is always true.
leeway = 60
bTimeValid = jwt.IsTimeValid(token,leeway)
print("time constraints valid: " + str(bTimeValid))

#  Now let's recover the original claims JSON (the payload).
payload = jwt.getPayload(token)
#  The payload will likely be in compact form:
print(payload)

#  We can format for human viewing by loading it into Chilkat's JSON object
#  and emit.
json = chilkat.CkJsonObject()
success = json.Load(payload)
json.put_EmitCompact(False)
print(json.emit())

#  We can recover the original JOSE header in the same way:
joseHeader = jwt.getHeader(token)
#  The payload will likely be in compact form:
print(joseHeader)

#  We can format for human viewing by loading it into Chilkat's JSON object
#  and emit.
success = json.Load(joseHeader)
json.put_EmitCompact(False)
print(json.emit())