Asymmetric Signature

Please Note

stringToSign component for Get Token and Transactional will be different!

  1. For Get Token = stringToSign = client_ID + “|” + X- TIMESTAMP

  2. For Transactional = stringToSign = HTTPMethod +":"+ EndpointUrl +":"+ Lowercase(HexEncode(SHA256(minify(RequestBody)))) + ":" + TimeStamp

Preparation

Before generating Signature, merchant need to prepare all the component required.

NameDescription

privateKey

Your privateKey

HTTPMethod

The HTTP method that client use to hit the API

endpointURL

The path of the endpoint that will be hitted e.g: /bi-snap-va/v1/transfer-va/create-va NOTE: For the HTTP Notification from DOKU to merchant server, this will be the path of merchant Notification URL. As for the Inquiry Request, this will be the path of merchant Inquiry URL

Timestamp

Same with X-TIMESTAMP

stringToSign

HTTPMethod +":"+ EndpointUrl +":"+ Lowercase(HexEncode(SHA256(minify(RequestBody)))) + ":" + TimeStamp

Set stringToSign Component

  1. Minify request Body

BeforeAfter

  1. Calculate the result of {minify-request-body} using SHA-256

The result will be like this :

3274fab8dac896837b106a16da2a974e7e65142dcecb4b768ef0294102838977
  1. Hexencode the result of {SHA-256(minify-request-body)}

The result will be like this :

3274fab8dac896837b106a16da2a974e7e65142dcecb4b768ef0294102838977

  1. Set the result of hexencode{SHA-256(minify-request-body)} to Lowercase

Generating StringtoSign

This is the formula for generating the string to Sign :

HTTPMethod +”:“+ EndpointUrl +":“+ Lowercase(HexEncode(SHA256(minify(RequestBody)))) + ":“ + TimeStamp

What is endpointURL ?

endpointURL means Request Target.

The Request-Target is depending on who is sending the request:

  1. When merchant hits DOKU endpoints: The Request-Target is the path of the DOKU API that merchant hits. For instance, if merchant wants to hit DOKU VA API: https://api.doku.com/bi-snap-va/v1/transfer-va/create-va. Therefore, the Request-Target value is /bi-snap-va/v1/transfer-va/create-va

  2. When DOKU hits merchant endpoints (HTTP Notification / Inquiry Request): The Request-Target is the path of merchant Notification URL or the Inquiry URL. For instance, if merchant set the Notification URL: https://yourdomain.com/payments/notifications. Therefore, the Request-Target value is /payments/notifications.

Generate Signature :

After all the stringToSign component has been set, merchant can now generate the signature :

  1. Calculate the result of (privateKey , stringToSign) using SHA256withRSA

    Ex : qd2m9ot+cfq48qJ68+8IYdfkNDMA2hhecM2XegsnZ1Z5Fur9zii8BVm6cI7g1gyhL5/+OFZqAO8Kp0XPMdipfg==

  2. Put the value to each API in X-Signature component in Request Header

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