Schema Registry — Integration Guide

Files to add to your project

Models/SchemaRegistryModels.cs        — Model classes + internal REST response shapes
Services/SchemaRegistryService.cs     — HttpClient wrapper for Confluent Schema Registry API
ViewModels/SchemaRegistryViewModel.cs — Full MVVM ViewModel
Views/SchemaRegistryView.xaml         — WPF UI (dark-themed, matches your DarkTheme.xaml)
Views/SchemaRegistryView.xaml.cs      — Code-behind (trivial)

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1. Models/KafkaCluster.cs

Ensure your cluster model has these properties:

public string? SchemaRegistryUrl { get; set; }
public string? SchemaRegistryUsername { get; set; }
public string? SchemaRegistryPassword { get; set; }

If you already have SchemaRegistryUrl but named differently, update the Initialise() call in SchemaRegistryViewModel.

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2. AddClusterDialog — add Schema Registry fields

In your AddClusterDialog.xaml, add input fields for the three properties above, e.g.:

<TextBlock Text="Schema Registry URL" .../>
<TextBox Text="{Binding SchemaRegistryUrl}" .../>

<TextBlock Text="Username (optional)" .../>
<TextBox Text="{Binding SchemaRegistryUsername}" .../>

<TextBlock Text="Password (optional)" .../>
<PasswordBox .../>   <!-- bind via converter or code-behind -->

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3. MainViewModel — wire up SchemaRegistryViewModel

public SchemaRegistryViewModel SchemaRegistryViewModel { get; } = new();

// Call this whenever SelectedCluster changes:
private void OnSelectedClusterChanged(KafkaCluster cluster)
{
    // existing wiring for brokers/topics/consumers...
    SchemaRegistryViewModel.Initialise(cluster);
}

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4. MainWindow.xaml — bind the view

Find the TabItem or content area where SchemaRegistryView is hosted and set its DataContext:

<TabItem Header="Schema Registry">
    <views:SchemaRegistryView
        DataContext="{Binding SchemaRegistryViewModel}"/>
</TabItem>

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5. Converters needed in App.xaml / DarkTheme.xaml

The XAML uses these converters (you likely already have them):

Key	Type	Description
BoolToVisibilityConverter	BooleanToVisibilityConverter	true → Visible
BoolToVisibilityInverter	custom	true → Collapsed
BoolInverter	custom	negates a bool

If BoolToVisibilityInverter or BoolInverter are missing, add them to your Converters/ folder:

// BoolToVisibilityInverter
public class BoolToVisibilityInverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
        => (bool)value ? Visibility.Collapsed : Visibility.Visible;
    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
        => throw new NotImplementedException();
}

// BoolInverter
public class BoolInverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
        => !(bool)value;
    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
        => !(bool)value;
}

And register in App.xaml or DarkTheme.xaml:

<converters:BoolToVisibilityInverter x:Key="BoolToVisibilityInverter"/>
<converters:BoolInverter x:Key="BoolInverter"/>

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Features implemented

• ✅ List all subjects with schema type, latest version, compatibility level
• ✅ Search/filter subjects
• ✅ View latest schema content (syntax-highlighted Consolas font)
• ✅ Version history with per-version delete
• ✅ Register new schema (Avro / JSON Schema / Protobuf) with template
• ✅ Add new version to existing subject
• ✅ Format JSON schema (pretty-print)
• ✅ Copy schema to clipboard
• ✅ Delete subject (all versions)
• ✅ View and update per-subject compatibility level
• ✅ Basic Auth support (username/password per cluster)
• ✅ Graceful "not configured" state when URL is empty
• ✅ Loading indicator + status bar messages

Not yet implemented (future work)

• Schema content syntax highlighting (requires AvalonEdit or similar)
• Schema compatibility pre-check before registering
• Protobuf-aware display
• Permanent hard-delete (?permanent=true)