Payment

Learn about Momen's built-in payment function. Build your native Stripe payment to boost your app's monetization.

Payment with Stripe

1. Preparation

1.1 Set Up a Stripe Account

• Sign up or log in to Stripe.

• Obtain your Publishable Key and Secret Key from the Stripe Dashboard.

1.2 Upgrade Your Project

Ensure your project is on the Pro plan or higher to enable payment features.

1.3 Create an Order Table

Before activating payment, you must create an Order Table in your project. This table will store essential order information like:

Field	Example
price	99.99
userId	user_123
status	pending

Warning: Once the order table is linked to payment features, it cannot be unlinked, replaced, or deleted.

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2. Activating Stripe Payment

2.1 Enable Payment

Navigate to Configuration → Payment, and activate the payment module.

Once activated, the system will automatically:

• Create three backend tables:

  • Payment Table: Stores one-time payment records.

  • Recurring Payment Table: Manages subscription billing.

  • Refund Table: Tracks refund transactions.

• Generate four system Actionflows:

  • StripePaymentCallback

  • StripeRefundCallback

  • StripeRecurringPaymentManagementCallback

  • StripeRecurringPaymentDeductionCallback

These system-generated flows securely handle payment event processing in the backend.

2.2 Configure Stripe Credentials

Input the following information into your project settings:

Field	Where to Find
Publishable Key	Stripe Dashboard
Secret Key	Stripe Dashboard

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3. Using Payment Actions

3.1 One-Time Payment

Use the Stripe Payment Action to charge users.

Parameter	Type	Description
orderId	Integer	The ID from the order table
currency	String	Currency code (e.g., USD)
amount	Decimal	Charge amount (in smallest currency unit, e.g., cents for USD)

Tip: To charge $10.00 USD, input 1000 because Stripe expects cents.

3.2 Refund Payment

Use the Stripe Refund Action to refund a payment.

Parameter	Type	Description
paymentId	Integer	The ID from the payment table
refundAmount	Decimal	Amount to refund (must not exceed the original payment amount)

Important: Restrict refund permissions to admin users to avoid financial risks.

3.3 Recurring (Subscription) Payments

Before initiating recurring payments:

• Create a Recurring Price object in Stripe.

• Obtain the Price ID.

Parameter	Type	Description
orderId	Integer	The ID from the order table
priceId	String	The Stripe-generated Price ID

Recurring actions allow:

• Starting a subscription

• Canceling an existing subscription

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4. Handling Payment Events via Actionflows

Stripe automatically triggers backend Actionflows for different payment events. These Actionflows allow you to parse the event data, validate results, and configure your own business logic securely.

Here are the main Actionflows provided:

4.1 Stripe Payment Callback

• Trigger: After a successful one-time payment

• System:

  • Parse payment data (e.g., orderId, paymentStatus)

  • Ensure duplicate callbacks are detected via callbackProcessed

• Custom business logic:

  • Update the order status to paid

  • Grant access to purchased services

  • Send a confirmation email or notification

4.2 Stripe Refund Callback

• Trigger: After a successful refund

• System:

  • Parse refund data

  • Detect duplicate callbacks

• Custom business logic:

  • Update the order status to refunded

  • Adjust user benefits or subscriptions

  • Notify the user about the refund

4.3 Stripe Recurring Payment Management Callback

• Trigger: Upon starting or canceling a subscription

• System:

  • Update the Recurring Payment Table

• Custom business logic:

  • Activate or deactivate subscription-based features

4.4 Stripe Recurring Payment Deduction Callback

• Trigger: When Stripe automatically charges for subscription renewal

• System:

  • Create a new order record

• Custom business logic:

  • Mark subscription as renewed

  • Notify the user about renewal success and next billing cycle

Tip: Customize each Actionflow to suit your app's logic, such as sending receipts, adjusting access rights, or linking to CRM systems.

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5. Retrieving Payment and Refund Status (Frontend)

Since payment operations are asynchronous:

• Subscribe to the Payment or Refund tables while using a list component to display results.

• Listen for real-time updates to refresh the frontend dynamically.

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6. Best Practices

• Validate input parameters before initiating payments.

• Cross-check the order amount and payment amount after a payment succeeds.

• Handle duplicate callbacks using callbackProcessed.

• Restrict sensitive operations like refunds to admins.

• Monitor your Stripe account for unusual activities.

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7. Common Issues and Troubleshooting

Problem	Cause	Solution
Incorrect charge amount	Misunderstanding Stripe's smallest unit format	Always multiply amounts by 100 for currencies like USD
Payment not reflected in order	Missing or misconfigured callback Actionflow	Ensure callback Actionflows are properly set up
Refund not updating order	Refund callback not processed	Check the refund callback subscription and flow

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8. Handling Expiration of the Pro Plan

After the Pro Plan expires, payment requests for online applications will result in errors, and the Project will not be able to be published. At this point, you can:

• Renew the Pro Plan. After renewal, the Project can be published normally, and online Payment will resume.

• Disable Payment. You can disable Payment in the Payment settings panel, which will clear the Payment configuration and Actionflow; after deploying the backend, data in the Payment, Recurring Payment, and Refund tables will also be cleared. Once Payment is disabled, the Project can be published normally.

👌 Conclusion

By following this guide, you can seamlessly integrate Stripe payments into your project, offering users a secure, scalable, and professional checkout experience.

Remember: Always rely on secure backend Actionflows rather than frontend assumptions for critical payment processes.

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Quick Payment Action Flow

flowchart LR
    A[User Initiates Payment] --> B{Payment System}
    B --> C{Stripe}
    C --> D[Payment Success/Failure Callback]
    D --> E[Update Order Table]
    E --> F[Update Frontend via Subscription]