KakaoPay

Introduction

KakaoPay is a payment method which allows to process payments in South Korean wons by using the digital wallet in the Republic of Korea. This method supports purchases and refunds.

This article provides information about working with the KakaoPay method: general insights are presented in the Overview section, while information about the actions required to process payments and perform other actions is presented in the sections that follow.

General information

Interaction diagram

Payment processing by using the KakaoPay method involves the merchant's web service, one of the ecommpay interfaces, the ecommpay payment platform, and technical facilities of the KakaoPay service.

Processing scenarios

To perform a purchase by using the KakaoPay method, you need to display the payment instructions to the customer, while to make a refund, you need to receive a request from the customer and notify the customer about the result of the refund via the web service.

Figure: Purchase by using Payment Page

Figure: Purchase by using Gate

Figure: Refund by using Gate

Scenarios for performing operations via the main interfaces of the payment platform correspond to those presented in the diagrams. Similarly, when additional features (such as payment links) are used, scenarios for performing operations also correspond to the specifics of those features.

General information

To process a purchase through Payment Page by using the KakaoPay method, the merchant's web service is required to send a request with all required parameters and signature to the ecommpay URL and receive a callback with the result. The full sequence and special aspects of purchase processing are provided below.

Information about the formats of requests and callbacks used for processing payments by using the KakaoPay method via Payment Page is presented further in this section; general information about working with the Payment Page API is presented in Interaction concepts.

Request format

There are several things you need to consider when sending purchase requests by using the KakaoPay method:

1. The following parameters required for any payment must be specified:
   • project_id—project identifier obtained from ecommpay during integration
   • payment_id—payment identifier unique within the project
   • payment_currency—payment currency code in the ISO-4217 alpha-3 format
   • payment_amount—payment amount in the smallest currency unit
   • customer_id—customer identifier unique within the project
2. The following parameters required for any payment must be specified: project_id, payment_id, payment_currency, payment_amount, customer_id.
3. The currency of the payment can only be KRW.
4. If you need to have the payment form displayed with the KakaoPay method selected, set the force_payment_method parameter to kakaopay-wallet.
5. Additionally, any other parameters available for working with Payment Page can be used (details).
6. After all target parameters are specified, generate a signature (details).

Thus, a correct request for opening the payment form using the KakaoPay method must contain the project identifier, basic payment information (identifier, amount, and currency code), customer identifier and signature.

{
   "project_id": 120,
   "payment_id": "580",
   "payment_amount": 1000,
   "payment_currency": "KRW",
   "customer_id": "customer1",
   "signature": "kUi2x9dKHAVNU0FYldOcZzUCwX6R\/ekpZhkIQg=="
}

{
   "project_id": 120,
   "payment_id": "580",
   "payment_amount": 1000,
   "payment_currency": "KRW",
   "customer_id": "customer1",
   "signature": "kUi2x9dKHAVNU0FYldOcZzUCwX6R\/ekpZhkIQg=="
}

Callback format

The KakaoPay method uses the standard format for callbacks to deliver purchase results. For more information, see Callbacks.

The following is the example of a callback with information about a 1000 KRW purchase made by the customer1 customer in the 1234 project.

{
        "project_id": 1234,
        "payment": {
            "id": "ABC123",
            "type": "purchase",
            "status": "success",
            "date": "2020-12-10T10:44:49+0000",
            "method": "kakaopay",
            "sum": {
                "amount": 1000,
                "currency": "KRW"
            },
            "description": ""
        },
        "customer": {
            "id": "customer1"
        },
        "operation": {
            "id": 123,
            "type": "sale",
            "status": "success",
            "date": "2020-12-10T10:44:49+0000",
            "created_date": "2020-12-10T10:44:41+0000",
            "request_id": "46d13cf06a05f023ab53dd2d3d5c266a310001",
            "sum_initial": {
                "amount": 1000,
                "currency": "KRW"
            },
            "sum_converted": {
                "amount": 1000,
                "currency": "KRW"
            },
            "code": "0",
            "message": "Success",
            "provider": {
                "id": 12345,
                "payment_id": "ABC12345",
                "auth_code": ""
            }
        },
        "signature": "Q8ccLF2ERNK0fbnnVil8NPh8vx83gF4air3OQ=="
}

The following is the example of a callback with information about a declined purchase.

{
        "project_id": 1234,
        "payment": {
            "id": "ABC123",
            "type": "purchase",
            "status": "decline",
            "date": "2020-12-15T11:14:03+0000",
            "method": "kakaopay",
            "sum": {
                "amount": 1000,
                "currency": "KRW"
            },
            "description": ""
        },
        "customer": {
            "id": "customer1"
        },
        "operation": {
            "id": 12345,
            "type": "sale",
            "status": "decline",
            "date": "2020-12-15T11:14:03+0000",
            "created_date": "2020-12-15T11:13:54+0000",
            "request_id": "f70a332cee48f25311ea302c334cc18999001",
            "sum_initial": {
                "amount": 1000,
                "currency": "KRW"
            },
            "sum_converted": {
                "amount": 1000,
                "currency": "KRW"
            },
            "code": "20000",
            "message": "General decline",
            "provider": {
                "id": 1234,
                "payment_id": "",
                "auth_code": ""
            }
        },
        "signature": "ZAXzfe6IG0dMypLzKledh0Glk6uDiRy1Ql56GRGEQ=="
}

Useful links

The following articles can be useful when implementing purchases via Payment Page:

• Interaction concepts—about the interaction with the payment platform by using Payment Page.
• Signature generation and verification—about the procedure of generating and verifying signatures in requests and callbacks.
• Payment models and statuses—about the types, processing models, and possible statuses of supported payments and operations.
• One-time one-step purchase—about processing of one-time one-step purchases by using Payment Page.
• Information of operations performing—about error and response codes that are used in the payment platform to record information about performing of operations.

General information

To process a purchase through Gate by using the KakaoPay method, the merchant's web service is required to do the following:

1. Send a request with all the required parameters and signature to the ecommpay URL.
2. Receive an intermediate callback with the data for displaying the payment instructions and display the instructions to the customer.
3. Receive the final callback from the payment platform.

The full sequence and special aspects of purchase processing are provided below.

Information about the formats of requests and callbacks used for processing payments by using the KakaoPay method via Gate is presented further in this section. General information about working with the Gate API is presented in Interaction concepts.

Request format

There are several things you need to consider when sending purchase requests by using the KakaoPay method:

1. To initiate each purchase, send a separate POST request to the /v2/payment/wallet/kakaopay/sale endpoint. This endpoint refers to the /v2/payment/wallet/{payment_method}/sale endpoint group.
2. Each request must include the following objects and parameters:
   • Object general—general purchase information:
     • project_id—project identifier obtained from ecommpay during integration
     • payment_id—payment identifier unique within the project
     • signature—request signature generated after all required parameters are specified (details—in the Signature generation and verification) (details)
   • Object payment—payment information:
     • amount—payment amount in the smallest currency unit
     • currency—payment currency code in the ISO-4217 alpha-3 format
   • Object customer—customer information:
     • id—customer identifier unique within the project
     • ip_address—customer IP address relevant for the initiated payment
   • Object return_url—URL for customer redirection to the web service:
     • success—URL for redirection after a processed payment
     • decline—URL for redirection after a declined payment
     • return—URL for redirection during or after the payment processing
3. The currency of the payment can only be KRW.
4. Additionally, any other parameters included in the specification can be used.

Thus, a correct purchase request by using the KakaoPay method must contain the project identifier, basic payment information (identifier, amount, and currency code), customer identifier and IP address, signature, and the URL for redirecting the customer to the web service.

{
  "general": {
    "project_id": 210,
    "payment_id": "test_payment",
    "signature": "PJkV8ej\/UG0Di8hTng6JvipTv+AWoXW\/9MTO8yJA=="
  },
  "payment": {
    "amount": 1000,
    "currency": "KRW"
  },
  "customer": {
    "id": "customer123",
    "ip_address": "192.0.2.0"
  },
  "return_url": {
    "decline": "http://example.com/decline",
    "success": "http://example.com/success",
    "return": "http://example.com/return"
  }
}

{
  "general": {
    "project_id": 210,
    "payment_id": "test_payment",
    "signature": "PJkV8ej\/UG0Di8hTng6JvipTv+AWoXW\/9MTO8yJA=="
  },
  "payment": {
    "amount": 1000,
    "currency": "KRW"
  },
  "customer": {
    "id": "customer123",
    "ip_address": "192.0.2.0"
  },
  "return_url": {
    "decline": "http://example.com/decline",
    "success": "http://example.com/success",
    "return": "http://example.com/return"
  }
}

Format of intermediate callbacks for displaying payment instructions

Each payment made with the KakaoPay method requires displaying payment instructions to customers. To display payment instructions, it is necessary to receive an intermediate callback from the payment platform and use the information included in the display_data array. The format of such callbacks is standard (details), and the following objects and parameters are included in the display_data array:

• type—type of data (the value is always qr_img)
• title—the name of the transferred data that needs to be displayed to the customer (the value is always QR code)
• data—a string based on which a QR code should be generated on the web service side (according to ISO/IEC 18004:2015)

"display_data": [
            {
                "type": "qr_img",
                "title": "QR code",
                "data": "data:image/png;base64,iVBORw0KGgW88NAAAAAElFTkSuQmCC"
            }
]

Final callback format

The KakaoPay method uses the standard format for callbacks to deliver purchase results. For more information, see Callbacks.

The following is the example of a callback with information about a 1000 KRW purchase made by the customer1 customer in the 1234 project.

{
        "project_id": 1234,
        "payment": {
            "id": "ABC123",
            "type": "purchase",
            "status": "success",
            "date": "2020-12-10T10:44:49+0000",
            "method": "kakaopay",
            "sum": {
                "amount": 1000,
                "currency": "KRW"
            },
            "description": ""
        },
        "customer": {
            "id": "customer1"
        },
        "operation": {
            "id": 123,
            "type": "sale",
            "status": "success",
            "date": "2020-12-10T10:44:49+0000",
            "created_date": "2020-12-10T10:44:41+0000",
            "request_id": "46d13cf06a05f023ab53dd2d3d5c266a31c5001",
            "sum_initial": {
                "amount": 1000,
                "currency": "KRW"
            },
            "sum_converted": {
                "amount": 1000,
                "currency": "KRW"
            },
            "code": "0",
            "message": "Success",
            "provider": {
                "id": 12345,
                "payment_id": "ABC12345",
                "auth_code": ""
            }
        },
        "signature": "Q8ccLF2ERNK0fbnnVil8NPh8vx83gF4aift64Zr3OQ=="
}

The following is the example of a callback with information about a declined purchase.

{
        "project_id": 1234,
        "payment": {
            "id": "ABC123",
            "type": "purchase",
            "status": "decline",
            "date": "2020-12-15T11:14:03+0000",
            "method": "kakaopay",
            "sum": {
                "amount": 1000,
                "currency": "KRW"
            },
            "description": ""
        },
        "customer": {
            "id": "customer1"
        },
        "operation": {
            "id": 12345,
            "type": "sale",
            "status": "decline",
            "date": "2020-12-15T11:14:03+0000",
            "created_date": "2020-12-15T11:13:54+0000",
            "request_id": "f70a332cee48f25311ea302c334cc189993a8d40001",
            "sum_initial": {
                "amount": 1000,
                "currency": "KRW"
            },
            "sum_converted": {
                "amount": 1000,
                "currency": "KRW"
            },
            "code": "20000",
            "message": "General decline",
            "provider": {
                "id": 1234,
                "payment_id": "",
                "auth_code": ""
            }
        },
        "signature": "ZAXzfe6IG0dMypLzKledh0Glk6uDiRy1Ql5xO+c86GRGEQ=="
}

Useful links

The following articles can be useful when implementing purchases via Gate:

• Interaction concepts—about the interaction with the payment platform by using Gate.
• Signature generation and verification—about the procedure of generating and verifying signatures in requests and callbacks.
• Payment models and statuses—about the types, processing models, and possible statuses of supported payments and operations.
• One-time one-step purchase—about processing of one-time one-step purchases by using Payment Page.
• Information of operations performing—about error and response codes that are used in the payment platform to record information about performing of operations.

General information

To perform a refund through Gate by using the KakaoPay method, send a request with all required parameters and signature to the ecommpay URL and receive a callback with the result. The full sequence and special aspects of refund performing are provided below.

Information about the formats of requests and callbacks used for performing refunds by using the KakaoPay method via Gate is presented further in this section. General information about working with the Gate API is presented in Interaction concepts.

Request format

There are several things you need to consider when sending refund requests by using the KakaoPay method:

1. To initiate each refund, send a separate POST request to the /v2/payment/wallet/kakaopay/refund endpoint. This endpoint refers to the /v2/payment/wallet/{payment_method}/refund endpoint group.
2. Each request must include the following objects and parameters:
   • Object general—general refund information:
     • project_id—project identifier obtained from ecommpay during integration
     • payment_id—identifier of the payment that needs to be refundedpayment identifier
     • signature—request signature generated after all required parameters are specified (details—in the Signature generation and verification)
   • Object payment—refund information:
     • description—refund description or comment
     • amount—refund amount in the smallest currency unit (required for a partial refund)
     • currency—refund currency code in the ISO-4217 alpha-3 format (required for a partial refund)
3. The currency of the refund can only be KRW.
4. Additionally, any other parameters included in the specification can be used.

Thus, a correct refund request by using the KakaoPay method must contain the project and payment identifiers, description of the refund, signature, and, if necessary, currency code and refund amount.

{
  "general": {
    "project_id": 210,
    "payment_id": "test_payment",
    "signature": "PJkV8ej\/UG0Di8hTng6JvipTv+AWoXW\/9MTO8yJA=="
  },
  "payment": {
    "description": "test refund",
    "amount": 1000,
    "currency": "KRW"
  },
  "customer": {
    "ip_address": "192.0.2.0"
  }
}

{
  "general": {
    "project_id": 210,
    "payment_id": "test_payment",
    "signature": "PJkV8ej\/UG0Di8hTng6JvipTv+AWoXW\/9MTO8yJA=="
  },
  "payment": {
    "description": "test refund",
    "amount": 1000,
    "currency": "KRW"
  },
  "customer": {
    "ip_address": "192.0.2.0"
  }
}

Callback format

The KakaoPay method uses the standard format for callbacks to deliver refund results. For more information, see Callbacks.

The following is the example of a callback with information about a 1000 KRW refund made for the customer1 customer in the 1234 project.

{
        "project_id": 1234,
        "payment": {
            "id": "ABC123",
            "type": "purchase",
            "status": "refunded",
            "date": "2020-12-15T11:15:58+0000",
            "method": "kakaopay",
            "sum": {
                "amount": 0,
                "currency": "KRW"
            },
            "description": "refund"
        },
        "customer": {
            "id": "customer1"
        },
        "operation": {
            "id": 12345,
            "type": "refund",
            "status": "success",
            "date": "2020-12-15T11:15:58+0000",
            "created_date": "2020-12-15T11:15:54+0000",
            "request_id": "74e1b0af0242c7d562f991b2203794fe48d0001",
            "sum_initial": {
                "amount": 1000,
                "currency": "KRW"
            },
            "sum_converted": {
                "amount": 1000,
                "currency": "KRW"
            },
            "code": "0",
            "message": "Success",
            "provider": {
                "id": 3456,
                "payment_id": "",
                "auth_code": ""
            }
        },
        "signature": "sfDbm8f+3edPKxf10/0K5btjGDOeOToXxg8xg=="
}

The following is the example of a callback with information about a declined refund.

{
        "project_id": 1234,
        "payment": {
            "id": "customer1",
            "type": "purchase",
            "status": "success",
            "date": "2020-12-15T11:17:19+0000",
            "method": "kakaopay",
            "sum": {
                "amount": 1000,
                "currency": "KRW"
            },
            "description": "refund"
        },
        "customer": {
            "id": "customer1"
        },
        "operation": {
            "id": 2345,
            "type": "refund",
            "status": "decline",
            "date": "2020-12-15T11:17:19+0000",
            "created_date": "2020-12-15T11:17:17+0000",
            "request_id": "1d098669df63438f1a4079193218543f22c40160-4a9e0001",
            "sum_initial": {
                "amount": 1000,
                "currency": "KRW"
            },
            "sum_converted": {
                "amount": 1000,
                "currency": "KRW"
            },
            "code": "20000",
            "message": "General decline",
            "provider": {
                "id": 3456,
                "payment_id": "",
                "auth_code": ""
            }
        },
        "signature": "04fZ8UZhuCXotsbI+8sqk98hegbVEYc3iAfFOYx8XmBUWkHf/HIA=="
}

Useful links

The following articles can be useful when implementing refunds via Gate:

• Interaction concepts—about the interaction with the payment platform by using Gate.
• Signature generation and verification—about the procedure of generating and verifying signatures in requests and callbacks.
• Payment models and statuses—about the types, processing models, and possible statuses of supported payments and operations.
• Purchase refunds—about performing of refunds by using Gate.
• Information of operations performing—about error and response codes that are used in the payment platform to record information about performing of operations.