## Requirements # 4. Requirements ## 4.1 Functional Requirements ### 4.1.1 Order Service - The system shall allow creation of a single order per API request. Bulk or batch order creation is not supported in the current implementation. [KB-459cbd85-fb6b-4a7e-8a36-e5f711cac6b9], [KB-4c9591c9-34d5-42b1-a0e2-1de20131159c], [KB-86e313b9-691a-4830-b560-a2097e138f34] - The system shall support paginated retrieval of order lists, with parameters `skip` (default 0) and `limit` (default 20). [KB-459cbd85-fb6b-4a7e-8a36-e5f711cac6b9], [KB-4287fde1-e2d9-4e31-8f2f-5c3f64f00add] - The system shall allow retrieval of order details by order ID, including itemized order contents. [KB-55d6e023-2c8e-49db-9409-68b9e9ed721f], [KB-4c9591c9-34d5-42b1-a0e2-1de20131159c] - The system shall support order status transitions: PENDING → PROCESSING → PAID → SHIPPED → DELIVERED. [KB-55d6e023-2c8e-49db-9409-68b9e9ed721f] - The system shall support order cancellation, updating status to CANCELLED. [KB-55d6e023-2c8e-49db-9409-68b9e9ed721f], [KB-459cbd85-fb6b-4a7e-8a36-e5f711cac6b9] - Upon order cancellation, the system shall trigger a refund request to the Payment Service and send a cancellation notification via the Notification Service. [KB-4651de1d-570d-4c49-8a65-ec5b22855797], [KB-981308db-2c30-4894-ba6b-491bf40b1d24], [KB-1a8a8c49-5d2d-4747-b2de-4e95950cdf44] - When order status is updated to SHIPPED, the system shall send a shipping notification. [KB-4287fde1-e2d9-4e31-8f2f-5c3f64f00add] - The system shall support webhook integration for payment status updates. Payment Service will call Order Service via POST /api/v1/orders/{order_id}/webhook with payment status and transaction ID. [KB-69d55b34-e506-4b4e-a043-ef842030f397], [KB-981308db-2c30-4894-ba6b-491bf40b1d24], [KB-564ae239-84b1-4ef2-bb04-b7e829eb53b6] ### 4.1.2 Payment Service - The Payment Service shall process payments for a single order per request. Bulk payment processing is not supported. [KB-8072a75f-d61d-49b1-a859-1be86806c449], [KB-8ca26148-03e1-4184-a736-624e14448df9], [KB-564ae239-84b1-4ef2-bb04-b7e829eb53b6] - Payment amount validation: minimum 100 JPY, maximum 1,000,000 JPY per transaction. [KB-8072a75f-d61d-49b1-a859-1be86806c449], [KB-299da2e5-721b-4ab1-9bb0-cd2d0f03c8c6], [KB-186b33d7-f985-455b-8117-0cd019912510] - The Payment Service shall enforce a 1:1 relationship between orders and payments (one payment per order). [KB-299da2e5-721b-4ab1-9bb0-cd2d0f03c8c6], [KB-8072a75f-d61d-49b1-a859-1be86806c449] - Duplicate payment requests for the same order_id shall be rejected. [KB-8072a75f-d61d-49b1-a859-1be86806c449], [KB-299da2e5-721b-4ab1-9bb0-cd2d0f03c8c6] - The Payment Service shall support refund processing for completed payments. [KB-8072a75f-d61d-49b1-a859-1be86806c449], [KB-36050440-5a8a-4389-8690-8e458c49f884], [KB-186b33d7-f985-455b-8117-0cd019912510] - Payment Service shall notify Order Service of payment status changes via webhook. [KB-564ae239-84b1-4ef2-bb04-b7e829eb53b6], [KB-4bd8168d-aed4-41eb-8733-2ab9d82daa22] ### 4.1.3 Notification Service - The Notification Service shall send email and SMS notifications for individual orders using templates. [KB-6155f440-0799-44eb-851f-9a5b81fbbcf8], [KB-582e7673-bd66-493e-b511-017708ae9326], [KB-1c5832cc-4e41-483e-9898-60c735170444] - The system shall support three notification templates: ORDER_CONFIRMATION, ORDER_SHIPPED, ORDER_CANCELLED. [KB-6155f440-0799-44eb-851f-9a5b81fbbcf8], [KB-1c5832cc-4e41-483e-9898-60c735170444] - Templates shall use Jinja2-style variable substitution and support Japanese language content. [KB-3133bf0e-2d7b-46bc-ae60-dac1a20281ed], [KB-6155f440-0799-44eb-851f-9a5b81fbbcf8], [KB-79cd66a7-e187-4f66-b53c-ded850690b2e] - Notification delivery status shall be tracked (PENDING, SENT, FAILED). [KB-6155f440-0799-44eb-851f-9a5b81fbbcf8], [KB-79cd66a7-e187-4f66-b53c-ded850690b2e] - The system shall allow retrieval of notification history by notification ID and retrieval of all notifications for a specific order. [KB-6155f440-0799-44eb-851f-9a5b81fbbcf8], [KB-1c5832cc-4e41-483e-9898-60c735170444], [KB-4d364408-238b-4248-925a-97d5a3446d3c] - Notification Service API rate limit: 10 requests per second for email notifications. [KB-582e7673-bd66-493e-b511-017708ae9326] ## 4.2 Constraints - Only single order creation, payment, and notification are supported per API request; bulk operations are not available. [KB-459cbd85-fb6b-4a7e-8a36-e5f711cac6b9], [KB-8072a75f-d61d-49b1-a859-1be86806c449], [KB-582e7673-bd66-493e-b511-017708ae9326], [KB-564ae239-84b1-4ef2-bb04-b7e829eb53b6] - Payment amount must be between 100 JPY and 1,000,000 JPY per transaction. [KB-8072a75f-d61d-49b1-a859-1be86806c449], [KB-299da2e5-721b-4ab1-9bb0-cd2d0f03c8c6] - Duplicate payments for the same order are prohibited. [KB-8072a75f-d61d-49b1-a859-1be86806c449], [KB-299da2e5-721b-4ab1-9bb0-cd2d0f03c8c6] - Refunds are only supported for completed payments. [KB-8072a75f-d61d-49b1-a859-1be86806c449], [KB-36050440-5a8a-4389-8690-8e458c49f884] - Notification Service rate limiting applies: 10 email notifications per second. [KB-582e7673-bd66-493e-b511-017708ae9326] ## 4.3 Interface Requirements ### 4.3.1 Order Service API | Endpoint | Description | Supported Operations | |----------------------------------------|----------------------------------------------|--------------------------| | POST /api/v1/orders/ | Create single order | Single order only | | GET /api/v1/orders/ | List orders (pagination: skip, limit) | Paginated list | | GET /api/v1/orders/{order_id} | Retrieve order details | By order ID | | PUT /api/v1/orders/{order_id}/status | Update order status | Triggers notifications | | DELETE /api/v1/orders/{order_id} | Cancel order | Triggers refund, notify | | POST /api/v1/orders/{order_id}/webhook | Payment status update (single order) | No batch webhook | [KB-459cbd85-fb6b-4a7e-8a36-e5f711cac6b9], [KB-4287fde1-e2d9-4e31-8f2f-5c3f64f00add], [KB-69d55b34-e506-4b4e-a043-ef842030f397], [KB-981308db-2c30-489e-ac30-457c4c49753b] ### 4.3.2 Payment Service API | Endpoint | Description | Supported Operations | |----------------------------------------|----------------------------------------------|--------------------------| | POST /api/v1/payments/ | Create payment for single order | Single order only | | GET /api/v1/payments/{payment_id} | Retrieve payment by payment ID | Individual payment | | GET /api/v1/payments/order/{order_id} | Retrieve payment for specific order | 1:1 order-payment | | POST /api/v1/payments/refund | Process refund for completed payment | Refund only if complete | [KB-8072a75f-d61d-49b1-a859-1be86806c449], [KB-36050440-5a8a-4389-8690-8e458c49f884], [KB-90c1a181-8f6a-4efe-be94-d7a6c0e37f5a] ### 4.3.3 Notification Service API | Endpoint | Description | Supported Operations | |---------------------------------------------|-----------------------------------------------------|--------------------------| | POST /api/v1/notifications/email | Send single email notification | Single order only | | POST /api/v1/notifications/sms | Send single SMS notification | Single order only | | GET /api/v1/notifications/{notification_id} | Retrieve notification by ID | Individual notification | | GET /api/v1/notifications/order/{order_id} | Retrieve all notifications for specific order | Multiple per order | [KB-582e7673-bd66-493e-b511-017708ae9326], [KB-1c5832cc-4e41-483e-9898-60c735170444], [KB-4d364408-238b-4248-925a-97d5a3446d3c] ## 4.4 Data Requirements - Order data must include customer name, email, itemized order details (product name, quantity, unit price), and currency. [KB-4c9591c9-34d5-42b1-a0e2-1de20131159c], [KB-1bfa4181-74da-4372-ba8f-acf6d7aa41c4] - Payment data must include order_id, amount, currency, payment status, payment method, transaction ID, and timestamps. [KB-90c1a181-8f6a-4efe-be94-d7a6c0e37f5a], [KB-36050440-5a8a-4389-8690-8e458c49f884] - Notification data must include order_id, channel (email/SMS), template name, recipient, subject, body, status, and timestamps. [KB-258b5996-5aad-4f5f-acd2-8e458c49f884], [KB-582e7673-bd66-493e-b511-017708ae9326] ## 4.5 Error Handling Requirements - All API error responses must follow RFC 7807 Problem Details for HTTP APIs standard. [KB-6353c73b-fdb1-409c-9679-739f0ab68585], [KB-4c9591c9-34d5-42b1-a0e2-1de20131159c] - Common error codes: - 400: Bad Request / Validation Error - 404: Resource Not Found - 422: Schema Validation Error - 500: Internal Server Error [KB-4bd8168d-aed4-41eb-8733-2ab9d82daa22] ## 4.6 [GAP: Missing data for Requirements] - Bulk CSV import functionality for orders is frequently requested and referenced, but is not currently implemented. [KB-155b5f4a-d232-4166-bb96-ba158f86ceb1], [KB-2183809f-cfa9-4b0b-a30d-320f78a4f161], [KB-94407aa3-d1ac-4455-a68c-265236fefec4], [KB-6ef0a78b-63b6-493a-a7b0-76398d5a2889], [KB-1603dccf-0e13-426d-a4c3-527af9e69c16], [KB-2b07b017-3e2f-47a4-9b03-d2be4a0e5644], [KB-5bd83fdc-f7d5-4953-bd1e-e9b287f0bf96], [KB-2c0207d4-673f-470e-a43e-d40dcd638bab], [KB-2b0238e6-fb8b-4c64-bbb0-73de35f73a08], [KB-5a963d29-d4ed-4859-ba71-d355620aa5bc], [KB-2708f598-e5da-4cca-91f0-fd3d267de542], [KB-25b436c5-c5b0-48c1-97de-61d50bd37e57], [KB-063a89e7-bb79-4435-993b-95ec7b9a9e4e], [KB-35c9e00d-f446-4174-be65-d214ecbff895], [KB-110bd1b1-0680-48fd-9bf9-6a5929dbbdec], [KB-0e0f1dd0-0f46-4d13-a092-e3cdc6fdd205], [KB-89dddd9a-2e13-46e7-99a4-34c3fff47435], [KB-6aa21c29-11f1-4b6b-b8e8-2c9990900522], [KB-0e28e3cb-6977-43b1-ba8e-1ed80f2de11e] --- **End of Requirements Section**