Yimaru Backend

Yimaru Backend is the server-side application that powers the Yimaru online learning system. It manages courses, lessons, quizzes, student progress, instructor content, and administrative operations for institutions and users on the platform.

Table of Contents

• Installation
• Environment Configuration
• Running the Application
• Database Management
• Testing and Code Quality
• API Documentation
• Project Structure
• Core Services Overview
• Roles and Access Control
• Code Organization Guidelines
• Further Details

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Installation

Before running the application, ensure you have the following installed:

• Go (1.20+ recommended)
• Docker
• Air — for live reloading during development
• SQLC
• Migrate
• Swag

Clone the repository:

git clone https://github.com/your-org/Yimaru-backend.git
cd Yimaru-backend

├── cmd/
│   └── main.go                  # Application entry point
├── internal/
│   ├── config/                  # Configuration and environment loading
│   │   └── config.go
│   ├── domain/                  # Domain models, constants, and roles
│   │   ├── course.go            # Course and lesson structures
│   │   └── roles.go             # Role definitions (e.g., RoleAdmin, RoleInstructor)
│   ├── repository/              # Database interaction layer
│   │   ├── course.go            # Course-related queries
│   │   ├── lesson.go            # Lesson-related database functions
│   │   ├── user.go              # User repository methods
│   │   └── ...                  # Other repository files
│   ├── services/                # Business logic and core services
│   │   ├── course/
│   │   │   └── service.go       # Course management logic
│   │   └── quiz/
│   │       ├── service.go       # Quiz management and evaluation logic
│   │       └── eval.go          # Evaluation logic for student progress
│   └── web_server/              # HTTP handlers, routes, middleware, and cron jobs
│       ├── cron.go              # Scheduled background tasks
│       └── handlers/
│           ├── course_handler.go   # Course-related API endpoints
│           ├── user_handler.go     # User-related endpoints
│           └── ...                 # Additional handlers
├── db/
│   └── migrations/              # SQL migration files
├── docs/
│   ├── swagger/                 # Swagger/OpenAPI documentation files
│   └── docs.go                  # Swaggo-generated docs
├── gen/
│   └── db/                      # SQLC-generated Go code for database access
├── makefile                     # Development and operations commands
├── .env                         # Environment configuration file
└── README.md                    # Project documentation


1. Course Category (Top-Level Classification)

Table: course_categories

Purpose:
Logical grouping of courses (e.g., Learning English, Other Courses).

Key Fields:

id – Primary identifier

name – Category name

is_active – Soft enable/disable

created_at – Audit timestamp

Relationships:

One Course Category → Many Course Sub-categories

Course Category
└── Course Sub-categories[]

2. Course Sub-category

Table: course_sub_categories

Purpose:
A grouping within a category (e.g., Speaking, Listening under Learning English).

Key Fields:

category_id – FK → course_categories.id

title, description

is_active

Relationships:

Belongs to one Course Category

Has many Courses

Course Category
└── Course Sub-category
    └── Courses[]

3. Course

Table: courses

Purpose:
A learning unit within a sub-category representing different skill levels
(e.g., Beginner, Intermediate, Advanced).

Key Fields:

sub_category_id – FK → course_sub_categories.id

title, description

thumbnail

display_order

level – BEGINNER | INTERMEDIATE | ADVANCED

is_active

Relationships:

Belongs to one Course Sub-category

Has many Course Videos

Has many Practices

Course Sub-category
└── Course
    ├── Course Videos[]
    └── Practices[]

4. Course Video

Table: course_videos

Purpose:
Video learning content attached to a course.

Key Fields:

course_id – FK → courses.id

title, description

video_url

duration, resolution

Publishing controls:

is_published

publish_date

visibility

instructor_id

thumbnail

display_order

is_active

Relationships:

Belongs to one Course

Course
└── Course Video

5. Practice

Table: practices

Purpose:
Exercises or assessments that belong to a course.

Key Fields:

course_id – FK → courses.id

title, description

banner_image

persona

is_active

Relationships:

Belongs to one Course

One Practice → Many Practice Questions

Course
└── Practice
    └── Practice Questions[]

6. Practice Question

Table: practice_questions

Purpose:
Individual questions within a practice session.

Key Fields:

practice_id – FK → practices.id

question

Voice support:

question_voice_prompt

sample_answer_voice_prompt

sample_answer

tips

type – MCQ | TRUE_FALSE | SHORT

Relationships:

Belongs to one Practice

Practice
└── Practice Question

Complete Hierarchical Flow (Compact View)
Course Category
└── Course Sub-category
    └── Course (with levels: BEGINNER, INTERMEDIATE, ADVANCED)
        ├── Course Video
        └── Practice
            └── Practice Question

Architectural Observations

Simple three-level hierarchy: Category → Sub-category → Course

Level is now a property of Course, not a separate entity

Cascade deletes ensure referential integrity

Schema is well-suited for:

LMS platforms

Progressive learning apps

Video + assessment-based education systems