FYI:We made this API to fit the needs of our cooperated partner to transfer funds to our user wallet with secure transactions.

Before you can access our API gateway you need to use the generated access token from our OAuth2 API. Make sure before you use our API gateway the access token does not expire.

API Introduction

Request url (sandbox): https://clientdev.kesspay.io/partnerapi/v1/token

We designed the easy way for our partners to integrate all API services in just one route. What you need to do is know the API service name and use its parameters dynamically based on its service name.

API Introduction

Request url (sandbox): https://clientdev.kesspay.io/partnerapi/v1/gateway

Headers

Field	Type	Required	Description
Authorization	String(1200)	YES	Bearer {access_token}

Sample Parameters

Field	Type	Required	Description
service	String(64)	YES	API gateway service name
sign_type	String(10)	NO	The signature algorithm default RSA2
...	...	...	...
sign	String	Yes	Generated signature based on sign_type and request parameters from your server.

Sample success response

Field	Type	Description
success	Boolean	The API response status (true).
code	Number	Http response code.
message	Text	Response code description.
data	Object	Response data.
sign_type	String(10)	The signature algorithm default RSA2
sign	String	Use it to verify the incoming response from the API.

Sample fail response

Field	Type	Description
success	Boolean	The API response status (false).
error_code	String(32)	The API response error code.
error_desc	Text	Error description.
sign_type	String(10)	Signature type. No for UNAUTHENTICATED
sign	String	Use it to verify the incoming response from the API. No for UNAUTHENTICATED

• Fund transfer is an option that our partners use to transfer funds from their user account’s wallet to our user’s wallet in real time. We have two different steps to complete the fund transfer process.
• Firstly, you need to request to create a unified fund transfer (pre-fund transfer) and you will get the pre-transfer ID and our user’s name to show your customer to make a confirmation.
• After that, you just need to DEBIT your customer wallet and request the confirmation fund transfer to the API server to finalize the process.

Headers

Field	Type	Required	Description
Authorization	String(1200)	YES	Bearer {access_token}

Sample Parameters

Field	Type	Required	Description
service	String(64)	YES	Value: create.unified.fundTransfer
sign_type	String(10)	NO	The signature algorithm default RSA2
out_trade_no	Alpha(64)	Yes	Your transfert unique reference number.
receiver_id	Alpha(25)	Yes	KESS user ID or phone number.
sender_name	String(96)	YES	Partner’s customer (sender) name.
amount	Double	YES	Transfer amount. Ex: 0.50
currency	Char(3)	Yes	Only USD allowed.
sign	String	Yes	Generated signature based on sign_type and request parameters.

Response success data

Field	Type	Description
out_trade_no	Alpha(64)	Your unique reference ID.
receiver_id	Alpha(25)	KESS user ID or phone number.
amount	Double	Transfer amount. Ex: 0.50
currency	Char(3)	Value: KHR/USD
pre_transfer_id	Alpha(64)	Unified unique ID - use it for transfer confirmation.
receiver_name	String(96)	Receiver name - show this name to sender for making a confirmation.
expire_in	Integer	The expiration time of created unified fund transfer in second.

Response fail

Field	Type	Description
success	Boolean	False
sign_type	String(10)	The signature algorithm default RSA2
error_code	String(32	NOTELIGIBLE/VALIDATIONERROR/SYSTEMERROR
error_desc	Text	The reason for the error.
sign	String	Generated signature based on sign_type and response body.

Error code review

HttpCode: 400, NOTELIGIBLE: Receiver is not eligible for the fund.

HttpCode: 400, VALIDATIONERROR: Parameters validation incorrect.

HttpCode: 500, SYSTEMERROR: Server error or busy.

Headers

Field	Type	Required	Description
Authorization	String(1200)	YES	Bearer {access_token}

Sample Parameters

Pre transfer ID got from created unified fund transfer.

Field	Type	Required	Description
service	String(64)	YES	Value: confirm.fundTransfer
sign_type	String(10)	NO	The signature algorithm default RSA2
partner_transaction_id	Alpha(64)	Yes	Your unique transaction ID of SUCCEED transaction between your customer and KESS bank account.
pre_transfer_id	Alpha(64)	Yes	KESS user ID or phone number.
sign	String	Yes	Generated signature based on sign_type and request parameters.

Response success data

Field	Type	Description
result_code	String(32)	SUCCESS.
fund_transfer_id	Alpha(64)	Fund transferred ID after CREDIT the receiver SUCCEED.
out_trade_no	Alpha(64)	Your unique reference ID.
receiver_id	Alpha(25)	KESS user ID or phone number.
pre_transfer_id	Alpha(64)	Unified unique ID - use it for transfer confirmation.
amount	Double	Transfer amount. Ex: 0.50
currency	Char(3)	Value: KHR/USD
receiver_name	String(96)	Receiver name - show this name to sender for making a confirmation.

Response fail

Field	Type	Description
success	Boolean	False
sign_type	String(10)	The signature algorithm default RSA2
error_code	String(32	USED/NOTEXIST/EXPIRED/VALIDATIONERROR/SYSTEMERROR
error_desc	String	The reason for the error.
sign	String	Generated signature based on sign_type and response body.

Error code review

HttpCode: 400, USED: Pre fund transfer ID is used.

HttpCode: 400, NOTEXIST: Wrong pre transfer ID, or invalid string.

HttpCode: 400, EXPIRED: Unified fund transfer is expired.

HttpCode: 400, VALIDATIONERROR: Validation error field value is invalid.

HttpCode: 500, SYSTEMERROR: Server error or busy.

Headers

Field	Type	Required	Description
Authorization	String(1200)	YES	Bearer {access_token}

Parameters

Field	Type	Required	Description
service	String(64)	YES	Value: query.fundTransfer
sign_type	String(10)	NO	The signature algorithm default RSA2
out_trade_no	Alpha(64)	Yes	Your unique reference ID that used to create unified fund transfer.
sign	String	Yes	Generated signature based on sign_type and request parameters.

Response success data

Field	Type	Description
result_code	String(32)	SUCCESS.
fund_transfer_id	Alpha(64)	Fund transferred ID after CREDIT the receiver SUCCEED. *Note: available for the result_code = SUCCESS only.
out_trade_no	Alpha(64)	Your unique reference ID.
amount	Double	Transfer amount. Ex: 0.50
currency	Char(3)	Value: KHR/USD
receiver_id	Alpha(25)	KESS user ID or phone number.
receiver_name	String(96)	Receiver name - show this name to sender for making a confirmation.

Response fail

Field	Type	Description
success	Boolean	False
sign_type	String(10)	The signature algorithm default RSA2
error_code	String(32	USED/NOTEXIST/EXPIRED/VALIDATIONERROR/SYSTEMERROR
error_desc	String	The reason for the error.
sign	String	Generated signature based on sign_type and response body.

Error code review

HttpCode: 400, NOTEXIST: Wrong pre transfer ID, or invalid string.

HttpCode: 400, EXPIRED: Unified fund transfer is expired.

HttpCode: 400, VALIDATIONERROR: Validation error field value is invalid.

HttpCode: 500, SYSTEMERROR: Server error or busy.

<?php

class RSA2

{

private static $PRIVATE_KEY = '{private key path}';

private static $PUBLIC_KEY = '{public key path}';

/**

* Get private key

* @return bool|resource

*/

private static function getPrivateKey()

{

return file_get_contents(self: : $PRIVATE_KEY);

}

/**

* Get public key

* @return bool|resource

*/

private static function getPublicKey()

{

return file_get_contents(self: : $PUBLIC_KEY);

}

/**

* Parse array to string

* @param array $data data

* @return string

*/

private static function toString(array $data)

{

ksort($data);

unset($data['sign_type'], $data['sign']);

return json_encode($data);

}

/**

* Create signature

* @param array $data data

* @return null|string

*/

public function createSign(array $data = [])

{

return openssl_sign(

self:: toString($data),

$sign,

self:: getPrivateKey(),

OPENSSL_ALGO_SHA256

) ? base64_encode($sign) : null;

}

/**

* Verifying signature

* @param array $data data

* @param string $sign autograph

* @return bool

*/

public function verifySign(array $data = [], string $sign = '')

{

return (bool) openssl_verify(

self: : toString($data),

base64_decode($sign),

self: : getPublicKey(),

OPENSSL_ALGO_SHA256

);

}

}

Make signature

$rsa2 = new RSA2();

$params['sign'] = $rsa2->createSign($params);

Verify signature

$rsa2 = new RSA2();

$isValidResponse = $rsa2->verifySign($response, $response['sign']);