Novault-backend/internal/models/TRANSACTION_EXTENSION_IMPLEMENTATION.md

Transaction Model Extension Implementation

Overview

This document describes the implementation of Task 1.5: 扩展Transaction模型 (Extend Transaction Model) from the accounting-feature-upgrade specification.

Implementation Summary

1. Model Extensions

Extended the Transaction model in backend/internal/models/models.go with the following new fields:

Multi-Ledger Support

• LedgerID (*uint): Associates transaction with a specific ledger
• Validates: Requirements 3.10

Precise Time Recording

• TransactionTime (*time.Time): Records precise transaction time (HH:mm:ss)
• Validates: Requirements 5.2

Reimbursement Fields

• ReimbursementStatus (string): Status of reimbursement (none, pending, completed)
• ReimbursementAmount (*float64): Amount to be reimbursed
• ReimbursementIncomeID (*uint): Links to the generated reimbursement income transaction
• Validates: Requirements 8.4-8.9

Refund Fields

• RefundStatus (string): Status of refund (none, partial, full)
• RefundAmount (*float64): Amount refunded
• RefundIncomeID (*uint): Links to the generated refund income transaction
• Validates: Requirements 8.10-8.18

Original Transaction Link

• OriginalTransactionID (*uint): Links refund/reimbursement income back to original expense
• IncomeType (string): Type of income (normal, refund, reimbursement)
• Validates: Requirements 8.19-8.22

New Relationships

• Ledger: Foreign key relationship to Ledger model
• Images: One-to-many relationship with TransactionImage
• OriginalTransaction: Self-referencing relationship for refund/reimbursement tracking

2. Database Migration

Created migration file: backend/migrations/003_extend_transaction_model.sql

The migration adds the following columns to the transactions table:

• transaction_time (TIME)
• reimbursement_status (VARCHAR(20), default: 'none')
• reimbursement_amount (DECIMAL(15,2))
• reimbursement_income_id (BIGINT UNSIGNED)
• refund_status (VARCHAR(20), default: 'none')
• refund_amount (DECIMAL(15,2))
• refund_income_id (BIGINT UNSIGNED)
• original_transaction_id (BIGINT UNSIGNED)
• income_type (VARCHAR(20))

Indexes created:

• idx_transactions_reimbursement_income_id
• idx_transactions_refund_income_id
• idx_transactions_original_transaction_id

3. Test Coverage

Created comprehensive test file: backend/internal/models/transaction_extension_test.go

Test functions:

1. TestTransactionExtensionFields: Verifies all new fields are properly set
2. TestTransactionReimbursementStatuses: Validates reimbursement status values
3. TestTransactionRefundStatuses: Validates refund status values
4. TestTransactionIncomeTypes: Validates income type values
5. TestTransactionDefaultValues: Verifies default values for new fields
6. TestTransactionRelationships: Verifies new relationship fields
7. TestTransactionPreciseTime: Tests precise time recording functionality
8. TestTransactionReimbursementFlow: Tests complete reimbursement workflow
9. TestTransactionRefundFlow: Tests complete refund workflow (full and partial)
10. TestTransactionOriginalLink: Tests original transaction linking
11. TestTransactionLedgerAssociation: Tests ledger association

All tests pass successfully ✓

4. Migration Execution

The migration was successfully executed using:

go run cmd/migrate/main.go

Results:

• ✓ All existing tables updated
• ✓ New transaction_images table created
• ✓ New user_settings table created
• ✓ System categories initialized (refund, reimbursement)

Field Details

Reimbursement Status Values

• none: No reimbursement requested
• pending: Reimbursement requested, awaiting confirmation
• completed: Reimbursement confirmed and income record created

Refund Status Values

• none: No refund processed
• partial: Partial refund (amount < original amount)
• full: Full refund (amount = original amount)

Income Type Values

• normal: Regular income transaction
• refund: Income generated from a refund
• reimbursement: Income generated from a reimbursement

Usage Examples

Creating a Transaction with Precise Time

transactionTime := time.Date(2024, 1, 15, 14, 30, 0, 0, time.UTC)
tx := Transaction{
    Amount:          100.00,
    Type:            TransactionTypeExpense,
    TransactionDate: transactionTime,
    TransactionTime: &transactionTime,
    LedgerID:        &ledgerID,
}

Applying for Reimbursement

reimbursementAmount := 80.00
expense.ReimbursementStatus = "pending"
expense.ReimbursementAmount = &reimbursementAmount

Processing a Refund

refundAmount := 50.00
incomeID := uint(200)
expense.RefundStatus = "partial"
expense.RefundAmount = &refundAmount
expense.RefundIncomeID = &incomeID

Creating Linked Income Record

refundIncome := Transaction{
    Type:                  TransactionTypeIncome,
    Amount:                50.00,
    IncomeType:            "refund",
    OriginalTransactionID: &originalExpenseID,
    LedgerID:              originalExpense.LedgerID, // Same ledger as original
}

Requirements Validation

This implementation validates the following requirements:

• ✓ 3.10: Multi-ledger transaction association
• ✓ 5.2: Precise time recording
• ✓ 8.4-8.9: Reimbursement workflow
• ✓ 8.10-8.18: Refund workflow
• ✓ 8.19-8.22: Original transaction linking
• ✓ 8.28: Ledger consistency for refund/reimbursement income

Next Steps

The Transaction model is now ready for:

1. Backend API implementation for reimbursement operations (Task 5.1)
2. Backend API implementation for refund operations (Task 5.2)
3. Frontend integration with transaction forms
4. Property-based testing for transaction workflows

Notes

• All pointer fields (*uint, *float64, *time.Time) are optional and can be nil
• Default values for status fields are set by GORM on database insert
• Foreign key constraints are commented out in the migration to avoid circular reference issues
• The implementation maintains backward compatibility with existing transactions