Game8 Store – Developer Center
Home › Technology & API

Sequence Diagram

📝 This is a reference translation. In case of any discrepancy, the Japanese version prevails.

This page describes the Out-of-app paymentThis page presents the sequence as a diagram.

In-game item purchase

👤 UserGame8 StoreGame (publisherAPI）👤 UserGame8 StoreGame (publisherAPI）Select product to purchaseRegister payment information1. Send credit card informationCredit card information2. e-Scott Transaction IDIssueTransaction IDPurchase product3. In-game item purchase (sent simultaneously withcredit card information)Transaction ID, In-game user ID, item ID,points to use4. In-game item purchase eligibility check (GET /check）Transaction ID, In-game user ID, itemID5. Reserve itemTransaction ID, In-game user ID, itemID6. Return check resultPurchase eligibility7. Recalculate payment amountopt[If a point usage amount is specified]8. Execute paymentTransaction ID, Payment amount, productinformation9. Return payment resultTransaction ID, Payment statusopt[If a balance remains after settlement with points]Immediate notification after successful payment10. Register in-game item sales record (POST /register）Transaction ID, In-game user ID, itemID11. Grant item12. Return item registration resultRegistration result13. Register purchase resultTransaction ID, User ID, in-game user ID,item ID, payment amount, etcConfirm immediate reflection for the user14. Display purchase completion screenItem registration result on the purchasescreen15. Send purchase notification emailPurchase notification email
Diagram source (mermaid)
sequenceDiagram
	autonumber
	actor user as User
	participant S8 as Game8 Store
	participant pub as Game (publisherAPI）

	## Select product to purchase

	# Register payment information
	user->>+S8: Send credit card information
	note right of user: Credit card information
	S8->>-user: e-Scott Transaction IDIssue
	note left of S8: Transaction ID

	# Purchase product
	user->>S8: In-game item purchase (sent simultaneously with credit card information)
	note right of user: Transaction ID, In-game user ID, item ID, points to use
	S8->>+pub: In-game item purchase eligibility check (GET /check）
	note right of S8: Transaction ID, In-game user ID, itemID
	pub->>pub: Reserve item
	note right of pub: Transaction ID, In-game user ID, itemID
	pub->>-S8: Return check result
	note left of pub: Purchase eligibility

	opt If a point usage amount is specified
	S8->>S8: Recalculate payment amount
	end
	opt If a balance remains after settlement with points
	S8->>+S8: Execute payment
	note right of S8: Transaction ID, Payment amount, product information
	S8->>-S8: Return payment result
	note left of S8: Transaction ID, Payment status
	end

	# Immediate notification after successful payment
	S8->>+pub: Register in-game item sales record (POST /register）
	note right of S8: Transaction ID, In-game user ID, itemID
	pub->>pub: Grant item
	pub->>-S8: Return item registration result
	note left of pub: Registration result
	S8->>S8: Register purchase result
	note over S8: Transaction ID, User ID, in-game user ID, item ID, payment amount, etc

	# Confirm immediate reflection for the user
	S8->>user: Display purchase completion screen
	note left of S8: Item registration result on the purchase screen
	S8->>user: Send purchase notification email
	note left of S8: Purchase notification email