Merchant-customized Checkout Integration

Under the Specific Payment Method integration mode, after a user places an order, they are redirected to the specified APM wallet page to make the payment. Under this integration mode, merchants need to develop their own checkout page.

1. Interaction Flow

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    'noteTextColor': '#ffffff',
    'noteBorderColor': '#004a99'
  }
}}%%
sequenceDiagram
    participant User as User
    participant Client as Merchant Client
    participant MServer as Merchant Server
    participant Checkout as PayerMax Cashier 
    participant PMServer as PayerMax Server
    participant Channel as Payment Channel
Wallet/Bank, etc.

    %% 1. Ordering Phase
    User->>Client: 1.1 Select product and place order
    Client->>MServer: 1.2 Place order
    MServer->>PMServer: 1.3 Create payment
Call Cashier checkout API
    PMServer->>PMServer: Create transaction
    PMServer-->>MServer: 1.4 Return payment creation response
Including PayerMax Cashier URL
    MServer-->>Client: 1.4 Return response
    Client->>Checkout: 2.1 Redirect to PayerMax Cashier page

    %% 2. Payment Phase
    User->>Checkout: 3.1 Select payment method
and submit payment
    Checkout->>PMServer: 3.2 Payment request
    PMServer->>Channel: 3.3 Payment request
    PMServer-->>Checkout: 3.4 Response
Including PayerMax payment result URL
    Checkout->>Checkout: 3.5 Redirect to PayerMax payment result page

    %% 3. Return to Merchant
    User->>Checkout: 4.1 User clicks [Return to Merchant]
    Checkout-->>Client: 4.2 Redirect to merchant-specified page

    %% 4. Obtain Payment Result
    rect rgb(235, 245, 255)
        Note over MServer, PMServer: Obtain Payment Result
        
        Note over MServer, PMServer: Via Payment Result Notification
        PMServer->>MServer: 5.1 Asynchronous notification of payment result
        MServer->>MServer: 5.2 Update payment status
        MServer-->>PMServer: 5.3 Return response

        Note over MServer, PMServer: Via Payment Order Query
        MServer->>PMServer: 6.1 Query payment transaction
        PMServer-->>MServer: 6.2 Transaction details, including payment result
        MServer->>MServer: 6.3 Update payment status
    end

2. API List

Associated Interaction Sequence	Call Direction	API PATH
4.1 Create payment, call checkout order creation API	Merchant -> PayerMax	/orderAndPay
4.4 Payment result asynchronous notification	PayerMax -> Merchant	/collectResultNotifyUrl
4.4 Query payment transaction	Merchant -> PayerMax	/orderQuery

3. Environment Information

• Test environment request address：https:// pay-gate-uat.payermax.com/aggregate-pay/api/gateway/ <Interface PATH>

• Production environment request address：https:// pay-gate.payermax.com/aggregate-pay/api/gateway/ <Interface PATH>

4. Integration Steps

4.1 Create Payment

Payments are created by calling the Create Payment/OrderAndPay API interface and initiating an HTTP POST request. Under the Specific Payment Method integration mode, the PayerMax checkout page will selectively display a portion of the available payment methods based on the request input parameters.

Note:

Merchants can specify the payment close time in seconds for a single payment via the interface entry expireTime, the value must be greater than 1800 (30 minutes) and less than 86400 (24 hours). If the value passed in is less than 1800, the system will reset to the minimum value of 30min; if the value passed in is greater than 86400, the system will reset to the maximum value of 86400. If the merchant does not specify it, the exact time to close the payment will be different depending on the payment method used.

4.1.1 Use non-CARD payment methods

Create Payment/orderAndPay API example of an interface request:

curl --request POST \
  --url https://pay-gate-uat.payermax.com/aggregate-pay/api/gateway/orderAndPay \
  --header 'Accept: application/json' \
  --header 'Content-Type: application/json' \
  --header 'sign: FPFVT3o227JrFRbqu19boZCpVVTF9KznxyRawUmxpfXilHV/0yK46haPhAjNu1hPUMy7Vw/ILXhfzffNm4Fj0apWknlTY9OJxnSoQxS9BTFtc61tn5yV1q69x/kkBl82/qwg+XTJ4fOzy7Mar3VaC1E2PlDA6RkkKBUyNE6RYgsdB+Su7an4+4HVTNAnoe74WyvBgxTLMNg28igBTdqxaO3w/UBY6ObVp7vkqkQGdL1Y+HgmMYaAVwrM3+ALWGId0sJ+YqTY4WJ+0xCRGhaSnybiIjZsQEYyID68WNUfuavDLDsEhaMm/HfQvf5p0R1Ltovp3wwJnEbQcjY458iX5A==' \
  --data '{
    "version": "1.4",
    "keyVersion": "1",
    "requestTime": "2025-05-14T17:25:39.064+08:00",
    "appId": "test7e94124c208abbfc7e2792ecfa",
    "merchantNo": "TEST0114787283",
    "data": {
        "outTradeNo": "TEST39627390559111746827473769",
        "integrate": "Hosted_Checkout",
        "subject": "IDR 53,000",
        "totalAmount": "53000",
        "currency": "IDR",
        "country": "ID",
        "userId": "1177295",
        "frontCallbackUrl": "https://www.your.com",
        "notifyUrl": "https://middlepay.your.com/api_server/v2/finance/callback/order/TEST39627390559111746827473769",
        "paymentDetail": {
            "paymentMethodType": "WALLET", # Designated Payment Method
            "targetOrg": "", # Undesignated Payment Method
        }
    }
}'

If you specify only the paymentMethodType but not the targetOrg, the PayerMax Cashier page will only show all the payment organizations under that payment method, but not the other payment methods. For example, if the payment country is Indonesia and the payment method is e-wallet, PayerMax Cashier page will show supported Indonesian e-wallets, such as DANA, OVO, GOPAY and so on. If targetOrg is specified as OVO at the same time, opening the returned link will directly redirect to the OVO wallet to complete the payment.

Create Payment/orderAndPay API example of an interface request:

{
    "msg": "Success.",
    "code": "APPLY_SUCCESS",
    "data": {
        "redirectUrl": "https://cashier-n.payermax.com/v2/index.html#/payments?merchantId=TEST0114787283&merchantAppId=test7e94124c208abbfc7e2792ecfa&country=ID&tradeToken=T2019051409242877928306&paymentMode=WALLET&language=id&token=3acc37542e204765a6d11b86bf0bc930&amount=53000&currency=IDR&version=1.4&cashierId=T2019051409242877928306&frontCallbackUrl=https%3A%2F%2Fwww.your.com&pmaxLinkV=1",
        "outTradeNo": "TEST39627390559111746827473769",
        "tradeToken": "T2019051409242877928306",
        "status": "PENDING"
    }
}

4.1.2 Use CARD payment methods

Create Payment/orderAndPay API example of an interface request:

curl --request POST \
  --url https://pay-gate-uat.payermax.com/aggregate-pay/api/gateway/orderAndPay \
  --header 'Accept: application/json' \
  --header 'Content-Type: application/json' \
  --header 'sign: FPFVT3o227JrFRbqu19boZCpVVTF9KznxyRawUmxpfXilHV/0yK46haPhAjNu1hPUMy7Vw/ILXhfzffNm4Fj0apWknlTY9OJxnSoQxS9BTFtc61tn5yV1q69x/kkBl82/qwg+XTJ4fOzy7Mar3VaC1E2PlDA6RkkKBUyNE6RYgsdB+Su7an4+4HVTNAnoe74WyvBgxTLMNg28igBTdqxaO3w/UBY6ObVp7vkqkQGdL1Y+HgmMYaAVwrM3+ALWGId0sJ+YqTY4WJ+0xCRGhaSnybiIjZsQEYyID68WNUfuavDLDsEhaMm/HfQvf5p0R1Ltovp3wwJnEbQcjY458iX5A==' \
  --data '{
    "version": "1.4",
    "keyVersion": 1,
    "requestTime": "2025-05-14T16:30:27.174+08:00",
    "appId": "test516e8ab74578be8eecd8c4803fbe",
    "merchantNo": "TEST010117960578",
    "data": {
        "outTradeNo": "test5141630270627",
        "integrate": "Hosted_Checkout",
        "subject": "US $4.99 Stargem",
        "totalAmount": 4.99,
        "currency": "USD",
        "country": "US",
        "frontCallbackUrl": "https://pay.your.com/official_v2/redirect/web_payermax_web_v1",
        "userId": "test_1743900006925",
        "reference": "gp_huq_u",
        "notifyUrl": "https://pay.your.com/official_v2/notify/web_payermax_web_v1",
        "paymentDetail": {
            "paymentMethodType": "CARD", # Designated payment Methods
            "allowedCardOrg": [ # Specify the deck, which can be empty
                "MASTERCARD" 
            ]
        }
    }'

If the merchant wants to limit the card brand that the user pays with, this can be done by setting the request entry paymentDetail.allowedCardOrg. As in the above example, if you specify the card brand as MASTERCARD, then when PayerMax renders the checkout page, it will only display payment organizations that support MASTERCARD. If allowedCardOrg is not specified, all contracted card brands will be displayed.

Create Payment/orderAndPay API example of an interface request:

{
    "msg": "Success.",
    "code": "APPLY_SUCCESS",
    "data": {
        "redirectUrl": "https://cashier-n.payermax.com/v2/index.html#/payments?merchantId=TEST010117960578&merchantAppId=test516e8ab74578be8eecd8c4803fbe&orderNo=test5141630270627&country=US&tradeToken=T2019051408217377899667&paymentMode=CARD&targetOrg=*&token=acd8b556379140ee9a6ea067d6e68e35&amount=4.99&currency=USD&version=1.4&cashierId=T2019051408217377899667&frontCallbackUrl=https%3A%2F%2Fpay.your.com%2Fofficial_v2%2Fredirect%2Fweb_payermax_web_v1&pmaxLinkV=1",
        "outTradeNo": "test5141630270627", # Merchant trade order number, consistent with outTradeNo in the request
        "tradeToken": "T2019051408217377899667", # PayermMax Transaction Number
    }
}

5.2 Jump to PayerMax checkout page

Create Payment/orderAndPay API The interface response redirectUrl represents the PayerMax checkout page URL, and after receiving the response, the merchant can redirect to jump to the PayerMax checkout page, where the user completes the payment.

5.3 Jump to payment result page

After the user completes the payment, the PayerMax Cashier page redirects to jump to the PayerMax Payment Results page.The PayerMax Payment Results page displays the results of the payment (as shown in the image below), and the page contains Close or Back button, when the user clicks on it, it jumps to the page frontCallBackUrl specified by the merchant.

Merchants should ensure that the frontCallBackUrl they pass in is available to external browsers. The differences between the different frontCallBackUrl forms of the jump are as follows:

frontCallBackUrl form	Jump flow after payment completion	Recommended or Not	Advantages	Disadvantages
Ordinaryh5 (http/https)	Stay in the system browser and display the H5 page	No	/	Does not have the ability to evoke an app
Built-in active evoke APP logic h5 (http/https)	Display this H5 page, and at the same time, the logic within the page actively recognizes the scenario for merchant app evocation action, or stays on this page	Yes	Flexible logic and controlled processes	Complex development, to evoke the APP still need to use URL Scheme or AppLink/Universal Link
URL Scheme (Customized scheme://)	The system automatically tries to evoke the APP specified by Scheme. If the APP exists and has permission, it can open the corresponding APP; If the APP does not exist or has no permission, it stays in the system browser and displays a blank page;	No	Easy to develop	No degradation logic, will show a blank page when APP is not evoked
AppLink/Universal Link (http/https)	The system automatically tries to evoke the APP specified by Scheme. If the APP exists and has permission, it can open the corresponding APP; If the APP doesn't exist or doesn't have permission, it stays in the system browser and displays the content of the degraded H5 page	Yes	Development logic is relatively simple, can be downgraded to use H5 to deal with business logic

The URL back to Merchant consists of two parts, the first part is theCreate Payment/orderAndPay API frontCallbackUrlof the interface request,the second part is the extra parameters attached to PayerMax. Below is a complete example of a jump URL:

The additional parameters attached to PayerMax include:

• outTradeNo：Merchant Order Number;

• tradeToken：PayerMax order number;

• status：Order Status. In particular, please do not use this value to update the merchant order status directly, you should follow Step 4: Get Payment Result as the basis for processing as a way to ensure the accuracy of the transaction status.