Wonnit – Backend

A service to revitalize local businesses by sharing idle time in spaces

Spring Boot + Kotlin based backend

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🚀 Overview

Domain

• Space registration/update/deletion, search/recommendation, rental (request → approval → return → re-registration), image/3D model upload

Infra

• AWS S3 Presigned URL, H2 (MySQL mode) test environment

Quality

• RFC 7807-based global exception handling, structured logging, controller unit tests

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📐 Architecture (ASCII)

[ Client (iOS) ]
|
| REST API
v
+-------------------------+
|     Controller Layer    |
+-----------+-------------+
|
v
+-------------------------+      +------------------------+
|       Service Layer     |----->|   GlobalException      |
|  - SpaceQueryService    |      |   (RFC 7807 Response)  |
|  - SpaceUpdateService   |      |   + LoggingStrategy    |
|  - SpaceRentService     |      +------------------------+
|  - SpaceImageService    |
|  - Space3DModelService  |
|  - ColumnQueryService   |
+-----------+-------------+
|
v
+-------------------------+      +------------------------+
|      Infrastructure     |      |        Database        |
|  - S3PresignService     |      |   (H2/MySQL compatible)|
|  - S3Uploader           |      +------------------------+
+-------------------------+

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🗄️ Entity Model

Space
├─ id: UUID (PK, from PrimaryKeyEntity)
├─ name, description
├─ category: SpaceCategory (enum)
├─ status: SpaceStatus (enum)
├─ addressInfo: AddressInfo (Embedded)
├─ operationalInfo: OperationalInfo (Embedded)
├─ amountInfo: AmountInfo (Embedded)
└─ phoneNumber: PhoneNumber (Value Object)

Column
└─ Main screen column (Top3 display data)

Embeddables
├─ AddressInfo(city, district, detail, lat, lng ...)
├─ OperationalInfo(days/hours ...)
├─ AmountInfo(price, unit = TimeUnit{HOUR, DAY, ...})
└─ PhoneNumber

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🔑 Key Features

Space Management

• Register/update/delete: ownership validation and authorization check
• Image/3D Model: Presigned URL issuance → client directly uploads to S3

Rental Process

• Request → Approval → Return → Re-registration state transitions managed consistently by SpaceRentService
• State-specific validation and exception handling

Search/Query

• SpaceQueryService: keyword/my spaces/recent/nearby spaces
• ColumnQueryService: main columns Top3

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🛠️ Technical Highlights

Service Layer Separation

• Clear responsibilities for Query / Update(Command) / Rent / Media (image/3D)

AWS Integration

• S3Uploader: upload/delete
• S3PresignService: generate PUT/GET Presigned URLs
• DefaultCredentialsProvider chain (environment variables/IAM Role/Profile)

Exception Handling (RFC 7807)

• GlobalExceptionHandler + ProblemDetailBuilder
• ExceptionFactory/ExceptionBuilder: unify domain error codes → HTTP exceptions

Logging

• LoggingStrategy + LogLevel for structured logs
• Traceability across services and exception handlers

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✅ Testing

Controller Unit Tests (Spring Boot Test + JUnit5 + MockMvc)

• ColumnControllerTest, CategoryControllerTest, ProfileControllerTest
• RecentSpaceUpdateControllerTest, SearchControllerTest
• SpaceRentControllerTest, SpaceUpdateControllerTest

Fixture

• SpaceFixture ensures consistency of domain test data

Coverage Goals

• Validation of API contract (request/response), state transitions, and exception flow stability

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📊 Tech Stack

• Language: Kotlin
• Framework: Spring Boot 3.x, Spring Data JPA
• DB: H2 (MySQL mode) (→ MySQL compatible)
• Infra: AWS S3 (Presigned URL), Spring Cloud AWS
• Error Handling: ProblemDetail (RFC 7807)
• Logging: Custom LoggingStrategy + LogLevel
• Testing: JUnit 5, Spring Boot Test, MockMvc

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🌟 Why It Wins

• Reliability: rental logic centered on state transitions + controller tests + RFC 7807 exception handling
• Scalability: Presigned URL-based large file traffic offloading, Service Layer separation
• Operability: logging strategy and consistent responses for easier monitoring/debugging
• Data Modeling: Embedded/VO/Enum usage preserves domain semantics

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📚 API Documentation

• Swagger UI: complete API specification, request/response examples, and field descriptions
• Open this link -> http://43.201.251.218:8080/swagger-ui/index.html

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⌛️ How to Run

1. clean build
2. docker buildx build --platform linux/amd64 -t maruhan/wonnit:latest .
3. docker push maruhan/wonnit:latest
4. Connect to EC2 and run docker-compose up -d

• Requires compose.yaml and .env file

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