# 🚀 GeoVLogSvc - Windows Service Deployment Guide

This README provides comprehensive instructions for installing, configuring, and managing the **GeoVLogSvc** Windows Service using the provided PowerShell installer. This service logs flight sensor data to HDF5 and ensures clean encryption and shutdown via Windows Service lifecycle integration.

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## 📦 Contents

- [Overview](#overview)
- [Prerequisites](#prerequisites)
- [Installation Instructions](#installation-instructions)
- [Script Details](#script-details)
- [Service Behavior](#service-behavior)
- [Uninstallation](#uninstallation)
- [Troubleshooting](#troubleshooting)
- [Security and Permissions](#security-and-permissions)
- [Support](#support)

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## 🧭 Overview

`GeoVLogSvc` is a .NET-based Windows Service that:

- Logs GPS and sensor data to `.h5` (HDF5) files in real time.
- Maintains a manifest describing each flight session.
- Automatically encrypts the manifest and securely deletes plaintext `.h5` on shutdown.
- Supports Windows 10+ shutdown lifecycle events, including `PreShutdown`.

This repository includes a PowerShell script (`Install-GeoVLogSvc.ps1`) to automate deployment without needing a dedicated installer (e.g., MSI) — ideal for development, testing, or field installs.

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## ✅ Prerequisites

Before installing the service, ensure the following:

- You are running **Windows 10 or newer**.
- You have **Administrator rights** (needed to create services and modify the registry).
- .NET Runtime matching the build target of `GeoVLogSvc.exe` is installed.

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## 🛠️ Installation Instructions

### Step 1: Build the Service
Ensure you have built the service using `Release` configuration:

```bash
# From Visual Studio or using CLI
dotnet build -c Release
```

### Step 2: Run the Installer
Run the PowerShell script **as Administrator**:

```powershell
Set-ExecutionPolicy Bypass -Scope Process -Force
.\Deployment\Install-GeoVLogSvc.ps1
```

You may optionally specify custom parameters:

```powershell
.\Deployment\Install-GeoVLogSvc.ps1 -ExePath "C:\GeoVLog\GeoVLogSvc.exe" -PreShutdownTimeoutMS 60000
```

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## 📋 Script Details

The PowerShell script performs the following:

1. **Creates the service**:
   - Internal name: `GeoVLogSvc`
   - Display name: `GeoVLog Sensor Logger`
   - Startup type: `Delayed Automatic` (starts shortly after boot)

2. **Sets recovery actions**:
   - Restart after 5s (1st failure), 10s (2nd), 60s (3rd)

3. **Configures PreShutdown timeout**:
   - Sets a registry value for `PreshutdownTimeout` (default: 60 seconds)

4. **Registers the EventLog source**:
   - Ensures `GeoVLogSvc` can write logs to the Windows Event Log

5. **Starts the service immediately**

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## ⚙️ Service Behavior

After installation:

- The service runs in the background — no console or window is visible.
- It starts automatically at system boot (after system-critical services complete).
- It creates a `Logs/` folder in its install directory.
- It writes `.h5` sensor logs and a binary flight manifest.
- At shutdown (including Windows shutdown), it:
  - Disposes the HDF5 logger
  - Finalizes and timestamps the manifest
  - Encrypts it using AES
  - Deletes the plaintext `.h5` file if configured to do so

All status and error messages are logged to the **Windows Event Viewer** under the **Application log** with source `GeoVLogSvc`.

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## 🧹 Uninstallation

To remove the service manually:

```powershell
Stop-Service GeoVLogSvc
sc.exe delete GeoVLogSvc
```

If you'd like a dedicated uninstall script, let us know.

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## 🛠 Troubleshooting

| Problem | Solution |
|--------|----------|
| `Access Denied` error | Make sure PowerShell is run as **Administrator** |
| Service not appearing in Services | Run `sc query GeoVLogSvc` to check registration |
| EventLog source error | Re-run the script to register source, or run `New-EventLog` manually |
| Cleanup not triggered on shutdown | Make sure PreShutdownTimeout is set and service is not forcibly killed too early |

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## 🔐 Security and Permissions

- The service runs by default as **LocalSystem**. If you require more isolation:
  - Consider creating a dedicated service user
  - Adjust permissions on the `Logs/` directory and network access as needed

The script sets the service SID type to `unrestricted` for compatibility with custom firewall or access rules.

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## 📞 Support / Next Steps

- For integration into a proper MSI installer: consider using WiX Toolset.
- For audit and traceability: ensure Event Logs are centralized or monitored.
- Questions or issues? Please document environment, Windows version, and full logs.

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© GeoVLog Project — All rights reserved.