Blocked countries
تفاصيل العمل
? BlockedCountries API
ASP.NET Core Web API (In-Memory System)
? Overview
BlockedCountries API is a .NET Core Web API project designed to manage blocked countries and validate IP addresses using a third-party geolocation service.
The system is fully in-memory (no database) and demonstrates clean architecture concepts such as separation of concerns, dependency injection, and background processing.
⚙️ Tech Stack
ASP.NET Core Web API (.NET 7/8)
Dependency Injection (Built-in DI Container)
HttpClient (External API Integration)
ConcurrentDictionary (Thread-safe In-Memory Storage)
Swagger (API Documentation)
Newtonsoft.Json
Hosted Services (Background Tasks)
? Key Concepts Implemented
RESTful API Design
In-Memory Data Storage
Thread Safety (ConcurrentDictionary)
External API Integration
Pagination & Filtering
Background Services
Logging System
IP Geolocation Validation
? Features
? Country Management
Block a country
Batch block multiple countries
Unblock a country
Retrieve blocked countries with pagination & search
⏳ Temporal Blocking
Block a country for a specific duration (1–1440 minutes)
Prevent duplicate temporal blocks
Automatically unblock expired countries via background service
? IP Services
Lookup IP address using external geolocation API
Auto-detect caller IP if not provided
Validate IP format
Handle API failures gracefully
? IP Block Validation
Check if IP belongs to a blocked country
Combine:
Permanent blocked list
Temporal blocked list
Log every attempt
? Logging System
Track all IP block attempts
Store:
IP Address
Country Code
Timestamp
Block Status
User Agent
Paginated log retrieval
? API Endpoints
? Countries Controller
Method Endpoint Description
POST /api/countries/block Block a single country
POST /api/countries/block/batch Block multiple countries
DELETE /api/countries/block/{countryCode} Unblock a country
GET /api/countries/blocked Get blocked countries (pagination + search)
POST /api/countries/temporal-block Temporarily block a country
? IP Controller
Method Endpoint Description
GET /api/ip/lookup Get IP geolocation info
GET /api/ip/check-block Check if IP is blocked + log attempt
? Logs Controller
Method Endpoint Description
GET /api/logs/blocked-attempts Get paginated blocked IP attempts
? Configuration
appsettings.json
{
"Logging": {
"LogLevel": {
"Default": "Information",
"Microsoft.AspNetCore": "Warning"
}
},
"AllowedHosts": "*",
"GeoLocation": {
"BaseUrl": "https://api.ipgeolocation...;,
"ApiKey": "YOUR_API_KEY_HERE"
}
}
? External API Used
This project uses:
IP Geolocation API
Provides:
Country Code
Country Name
ISP Information
Location Details
? System Architecture
Controllers
↓
Services
↓
InMemoryStore (ConcurrentDictionary)
↓
External API (IP Geolocation)
? Testing via Swagger
After running the project:
dotnet run
Open:
? Test Scenarios
1. Block Country
POST /api/countries/block
Expected: country added
2. Duplicate Block
Same request again
Expected: 409 Conflict
3. IP Lookup
GET /api/ip/lookup?ipAddress=8.8.8.8
Expected: country info returned
4. Check Block
GET /api/ip/check-block
Expected:
isBlocked = true/false
log created
5. Logs
GET /api/logs/blocked-attempts
Expected: paginated results
⏱ Temporal Block Rules
Duration must be between 1 and 1440 minutes
Duplicate temporal block → 409 Conflict
Expired blocks removed automatically via background service
? Thread Safety
All in-memory storage uses:
ConcurrentDictionary for safe concurrent access
Ensures correctness under multiple requests
?? Author
Developed as a .NET Core Backend Assignment demonstrating:
Clean Architecture
API Design Principles
External API Integration
In-Memory Data Handling
? Conclusion
This project demonstrates a production-style backend system without database dependency, focusing on:
✔ Clean Code ✔ Scalability ✔ Thread Safety ✔ Real-world API design patterns