OpenNordicStocks.Client 1.0.3

OpenNordicStocks.NET

OpenNordicStocks.NET is an open-source .NET service and SDK providing daily and historical stock data for Sweden, Denmark, and Finland (NASDAQ Nordic OMX). Free, cacheable, and CDN-ready — designed for developers and analysts who need reliable Nordic market data.

📦 Projects

This solution consists of four main projects:

OpenNordicStocks.Core

Core library containing models and provider interfaces for Nordic stock data.

Features:

• StockData - Model representing individual stock information
• StockSnapshot - Model representing a complete market snapshot
• IStockDataProvider - Interface for implementing data providers

OpenNordicStocks.Client

NuGet SDK for consuming stock data from the OpenNordicStocks CDN.

Installation:

dotnet add package OpenNordicStocks.Client

Usage:

using OpenNordicStocks.Client;

var services = new ServiceCollection();

services.AddHttpClient<IOpenNordicStocksClient, OpenNordicStocksClient>();
services.AddHybridCache();

var provider = services.BuildServiceProvider();
var client = provider.GetRequiredService<IOpenNordicStocksClient>();

// Get latest stock data
var latestSnapshot = await client.GetRateAsync();

Console.WriteLine(latestSnapshot);

OpenNordicStocks.Publisher

Console application that fetches stock data and publishes normalized JSON snapshots.

Usage:

export DATA_DIRECTORY=./data
dotnet run --project src/OpenNordicStocks.Publisher/OpenNordicStocks.Publisher.csproj

This project is designed to run as a GitHub Action on a daily schedule, automatically fetching and publishing stock data.

OpenNordicStocks.Tests

xUnit test project containing unit tests for all components.

Run tests:

dotnet test

🚀 Getting Started

Prerequisites

• .NET 9.0 SDK or later

Building the Solution

dotnet restore
dotnet build

Running Tests

dotnet test

📊 Data Format

Stock data is published as normalized JSON in the following format:

{
  "date": "2025-10-28T00:00:00Z",
  "stocks": [
    {
      "symbol": "VOLV-B",
      "name": "Volvo AB",
      "price": 245.50,
      "market": "OMX Stockholm",
      "currency": "SEK",
      "timestamp": "2025-10-28T17:37:44.7434313Z",
      "volume": 1500000,
      "change": 2.50,
      "changePercent": 1.03
    }
  ],
  "metadata": {
    "version": "0.1.0",
    "generatedAt": "2025-10-28T17:37:44.743672Z",
    "totalCount": 3,
    "markets": ["OMX Stockholm", "OMX Helsinki", "OMX Copenhagen"]
  }
}

🌐 CDN Access

Published data will be available via CDN at:

• Latest snapshot: https://cdn.opennordicstocks.net/data/latest.json
• Historical data: https://cdn.opennordicstocks.net/data/YYYY-MM-DD.json

🤖 Automation

Stock data is automatically updated daily via GitHub Actions:

• Scheduled to run at 6:00 PM UTC (after Nordic markets close)
• Runs Monday through Friday (weekdays only)
• Can also be manually triggered via workflow dispatch

📝 License

This project is licensed under the MIT License - see the LICENSE file for details.

🤝 Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

📧 Contact

Henrik Roschmann - @henrikroschmann

Project Link: https://github.com/henrikroschmann/OpenNordicStocks.NET