Signature

To enhance the security of our API interactions, we mandate the use of a Signature header. This additional security measure ensures that all requests are authenticated and verified, safeguarding sensitive data and preventing unauthorized access.

Prerequisites

  • API_SECRET_KEY: Munify will provide this to the customer.
  • CUSTOMER_ID: Munify’s Customer Identifier.

Steps

Concatenate the values of the following request body fields in sequence, omitting spaces and quotation marks

  • customer_id
  • request_timestamp
  • customer_reference
  • amount
  • currency
  • bank_code
  • payout_type
  • receiver_identifier

Customer json

{
  "request_timestamp": "2024-08-03T12:07:22.714321",
  "customer_reference": "36786798",
  "amount": 9600.00,
  "currency": "EGP",
  "bank_code": "MIDG",
  "payout_type": "WALLET",
  "receiver_identifier": "01XXXXXXXXX",
  ...
}

Output result

message="3897102024-08-03T12:07:22.714321367867989600.00EGPMIDGWALLET01XXXXXXXXX"
  • Sign the concatenated string with the API_SECRET_KEY
    • Method: HMAC
    • Hash Function: SHA-256

Since the API_SECRET_KEY is hex-encoded, you must convert it to its binary form before using it in the HMAC algorithm.

secret_key = bytes.fromhex('695c659755a58171daa2e694db3deb6b689799cf0cb100809287122ef88695c9')
hmac_signature = hmac.new(secret_key_bytes, message_bytes, hashlib.sha256)
signature= hmac_signature.digest()
  • Convert the signature to a hexadecimal string.
signature_hex_str = signature.hex()

Complete example of signature generation (in Python)

# Step 1: Import the required libraries
import hmac
import hashlib
import base64
 
# Step 2: Define your inputs
message = "3897102024-08-03T12:07:22.714321367867989600.00EGPMIDGWALLET01XXXXXXXXX"
secret_key = "695c659755a58171daa2e694db3deb6b689799cf0cb100809287122ef88695c9"
 
# Ensure the secret_key is bytes
secret_key_bytes = bytes.fromhex(secret_key)
 
# Ensure the message is bytes
message_bytes = message.encode()
 
# Step 3: Create HMAC signature
hmac_signature = hmac.new(secret_key_bytes, message_bytes, hashlib.sha256)
 
# Step 4: Generate signature
signature = hmac_signature.digest()
 
# Convert the signature to hexadecimal string
signature_hex_str = signature.hex()
 
print("Hex Signature:", signature_hex_str)
 
 
""" Output
 
Hex Signature: abbe80001fcd9a8b2326cbab4611560b34f90b370b0e3e318f95a2955daad302
 
"""

Useful links: