Planning and Architecture

Why Planning Matters

A well-planned project reduces risks, saves time, and ensures a successful outcome.

Project Planning

1. Define Scope

• What is included in the project
• What is excluded
• Project boundaries and constraints

2. Create Timeline

# 3-Month Timeline
Month 1: Requirements & Design
  - Requirements gathering
  - Architecture design
  - Database schema design
  - UI/UX mockups

Month 2: Development
  - Backend development
  - Frontend development
  - API implementation
  - Database implementation

Month 3: Testing & Deployment
  - Unit testing
  - Integration testing
  - UAT
  - Deployment
  - Documentation

3. Resource Allocation

• Team members and roles
• Budget and costs
• Tools and infrastructure
• Training requirements

4. Risk Management

# Risk Register
Risk: Data breach due to security vulnerabilities
Probability: Medium
Impact: High
Mitigation: Security audit, penetration testing, encryption

System Architecture

Common Architecture Patterns

1. Layered Architecture (N-Tier)

Presentation Layer (UI)
    ↓
Business Logic Layer (Services)
    ↓
Data Access Layer (Repositories)
    ↓
Database Layer

2. Clean Architecture

Domain Layer (Entities & Interfaces)
    ↓
Application Layer (Use Cases)
    ↓
Infrastructure Layer (Data Access, External Services)
    ↓
Presentation Layer (UI)

Technology Selection

Criteria for Selection

• Project requirements
• Team expertise
• Scalability needs
• Community support
• Cost considerations

Technology Stack Example

# Full Stack Example
Frontend: ASP.NET Core Razor Pages
Backend: C# .NET 10
Database: SQL Server
ORM: Entity Framework Core
Hosting: Azure
CI/CD: GitHub Actions

Database Design

Steps in Database Design

1. Identify entities and relationships
2. Create Entity-Relationship (ER) diagram
3. Normalize tables
4. Define primary and foreign keys
5. Create indexes for performance

# Example ER Diagram
Users
  - Id (PK)
  - Name
  - Email

Orders
  - Id (PK)
  - UserId (FK → Users.Id)
  - OrderDate
  - Status

API Design

RESTful API Principles

• Use HTTP methods: GET, POST, PUT, DELETE
• Use resource-based URLs: /api/users, /api/users/{id}
• Use status codes appropriately
• Version your API

# API Endpoints Example
GET    /api/users              → Get all users
GET    /api/users/{id}         → Get user by ID
POST   /api/users              → Create a new user
PUT    /api/users/{id}         → Update an existing user
DELETE /api/users/{id}         → Delete a user