Chilkat2-Python

JWS Using HMAC SHA-256

See more JSON Web Signatures (JWS) Examples

Creates a JSON Web Signatures (JWS) using HMAC SHA-256. Chilkat2-Python

import sys
import chilkat2

success = False

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

# First create the JWS Protected Header
jwsProtHdr = chilkat2.JsonObject()
jwsProtHdr.AppendString("typ","JWT")
jwsProtHdr.AppendString("alg","HS256")
print("JWS Protected Header: " + jwsProtHdr.Emit())

# Output:
# JWS Protected Header: {"typ":"JWT","alg":"HS256"}

jws = chilkat2.Jws()

# Set the HMAC key:
hmacKey = "AyM1SysPpbyDfgZld3umj1qzKObwVMkoqQ-EstJQLr_T-1qS0gZH75aKtMN3Yj0iPS4hcgUuTwjAzZr1Z9CAow"
signatureIndex = 0
jws.SetMacKey(signatureIndex,hmacKey,"base64url")

# Set the protected header:
jws.SetProtectedHeader(signatureIndex,jwsProtHdr)

# Set the payload.
bIncludeBom = False
payloadStr = "In our village, folks say God crumbles up the old moon into stars."
jws.SetPayload(payloadStr,"utf-8",bIncludeBom)

# Create the JWS
# By default, the compact serialization is used.
jwsCompact = jws.CreateJws()
if (jws.LastMethodSuccess == False):
    print(jws.LastErrorText)
    sys.exit()

print("JWS: " + jwsCompact)

# sample output:
# JWS: eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.SW4gb3VyIHZpbGxhZ2UsIGZvbGtzIHNheSBHb2QgY3J1bWJsZXMgdXAgdGhlIG9sZCBtb29uIGludG8gc3RhcnMu.bsYsi8HJ0N6OqGI1hKQ9QQRNPxxA5qMpcHLtOvXatk8

# Now load the JWS, validate, and recover the original text.
jws2 = chilkat2.Jws()

# Load the JWS.
success = jws2.LoadJws(jwsCompact)

# Set the MAC key used for validation.
signatureIndex = 0
jws2.SetMacKey(signatureIndex,hmacKey,"base64url")

# Validate the 1st (and only) signature at index 0..
v = jws2.Validate(signatureIndex)
if (v < 0):
    # Perhaps Chilkat was not unlocked or the trial expired..
    print("Method call failed for some other reason.")
    print(jws2.LastErrorText)
    sys.exit()

if (v == 0):
    print("Invalid signature.  The MAC key was incorrect, the JWS was invalid, or both.")
    sys.exit()

# If we get here, the signature was validated..
print("Signature validated.")

# Recover the original content:
print(jws2.GetPayload("utf-8"))

# Examine the protected header:

joseHeader = chilkat2.JsonObject()
success = jws2.GetProtectedH(signatureIndex,joseHeader)
if (success == False):
    print(jws2.LastErrorText)
    sys.exit()

joseHeader.EmitCompact = False

print("Protected (JOSE) header:")
print(joseHeader.Emit())

# Output:

# 	Signature validated.
# 	In our village, folks say God crumbles up the old moon into stars.
# 	Protected (JOSE) header:
# 	{ 
# 	  "typ": "JWT",
# 	  "alg": "HS256"
# 	}