add metadata module for razor pages

zero/Metadata/Metadata.cs

@@ -0,0 +1,24 @@
+namespace zero.Metadata;
+
+public class Metadata
+{
+  public string AppVersion { get; set; }
+
+  public string Title { get; set; }
+
+  public string PageName { get; set; }
+
+  public string Description { get; set; }
+
+  public string Image { get; set; }
+
+  public string Robots { get; set; }
+
+  public string Icon { get; set; }
+
+  public string Url { get; set; }
+
+  public string Author { get; set; }
+
+  //public string Schema { get; set; }
+}

zero/Metadata/MetadataModule.cs

@@ -0,0 +1,12 @@
+using Microsoft.Extensions.Configuration;
+using Microsoft.Extensions.DependencyInjection;
+
+namespace zero.Metadata;
+
+public class ZeroMetadataModule : ZeroModule
+{
+  public override void ConfigureServices(IServiceCollection services, IConfiguration configuration)
+  {
+    services.AddScoped<IMetadataService, MetadataService>();
+  }
+}

zero/Metadata/MetadataOptions.cs

@@ -0,0 +1,27 @@
+namespace zero.Metadata;
+
+public class MetadataOptions
+{
+  public List<string> TitleFragments { get; set; } = [];
+
+  public bool? NoIndex { get; set; }
+
+  public bool? NoFollow { get; set; }
+
+  public string Description { get; set; }
+
+  public string Icon { get; set; }
+
+  public string Image { get; set; }
+
+  public string Author { get; set; }
+
+  //public Schema Schema { get; set; }
+
+  public MetadataOptions() { }
+
+  public MetadataOptions(params string[] titleFragments)
+  {
+    TitleFragments.AddRange(titleFragments);
+  }
+}

zero/Metadata/MetadataService.cs

@@ -0,0 +1,59 @@
+using Microsoft.Extensions.Logging;
+using System.Reflection;
+
+namespace zero.Metadata;
+
+public class MetadataService : IMetadataService
+{
+  protected ILogger<MetadataService> Logger { get; private set; }
+
+  protected ILocalizer Localizer { get; private set; }
+
+
+  public MetadataService(ILogger<MetadataService> logger, ILocalizer localizer)
+  {
+    Logger = logger;
+    Localizer = localizer;
+  }
+
+
+  /// <inheritdoc />
+  public Metadata Generate(string pageName, MetadataOptions options)
+  {
+    Metadata model = new()
+    {
+      Description = options.Description,
+      Icon = options.Icon,
+      Image = options.Image,
+      Author = options.Author,
+      PageName = pageName,
+      AppVersion = Assembly.GetEntryAssembly().GetCustomAttribute<AssemblyInformationalVersionAttribute>().InformationalVersion
+    };
+
+    // generate robots
+    bool noIndex = options.NoIndex ?? false;
+    bool noFollow = options.NoFollow ?? false;
+    model.Robots = String.Format("{0},{1}", noIndex ? "noindex" : "index", noFollow ? "nofollow" : "follow");
+
+    // title
+    HashSet<string> fragments = options.TitleFragments.Where(x => !x.IsNullOrWhiteSpace()).Reverse().ToHashSet();
+    model.Title = !fragments.Any() ? pageName : (String.Join(" / ", fragments.Select(fragment => Localizer.Maybe(fragment))) + " / " + pageName);
+
+    // add schema
+    //if (options.Schema != null)
+    //{
+    //  model.Schema = options.Schema.ToJson();
+    //}
+
+    return model;
+  }
+}
+
+
+public interface IMetadataService
+{
+  /// <summary>
+  /// Generates metadata.
+  /// </summary>
+  Metadata Generate(string pageName, MetadataOptions options);
+}

zero/Metadata/Schema.cs

@@ -0,0 +1,53 @@
+//using Microsoft.AspNetCore.Mvc;
+//using System.Dynamic;
+
+//namespace zero.Metadata;
+
+//public class Schema
+//{
+//  public dynamic Model { get; private set; }
+
+//  static JsonOptions Settings;
+
+//  static Schema()
+//  {
+//    Settings = new JsonOptions()
+//    {
+//      Formatting = Formatting.None,
+//      TypeNameHandling = TypeNameHandling.None
+//    };
+//    Settings.Converters.Add(new SchemaConverter());
+//  }
+
+
+//  public Schema(string type, Action<dynamic> set) : this(type, false, set) { }
+
+//  public Schema(string type, bool isRoot, Action<dynamic> set)
+//  {
+//    Model = new ExpandoObject();
+//    var dict = Model as IDictionary<string, object>;
+//    if (isRoot)
+//    {
+//      dict["@context"] = "https://schema.org";
+//    }
+//    dict["@type"] = type;
+//    set(Model);
+//  }
+
+
+//  public string ToJson() => JsonConvert.SerializeObject(Model, Settings);
+
+
+//  class SchemaConverter : JsonConverter<Schema>
+//  {
+//    public override void WriteJson(JsonWriter writer, Schema value, JsonSerializer serializer)
+//    {
+//      serializer.Serialize(writer, value.Model);
+//    }
+
+//    public override Schema ReadJson(JsonReader reader, Type objectType, Schema existingValue, bool hasExistingValue, JsonSerializer serializer)
+//    {
+//      throw new NotImplementedException();
+//    }
+//  }
+//}

zero/Mvc/ZeroPageModel.cs

@@ -1,6 +1,6 @@
-using System.Net.Mime;
-using Microsoft.AspNetCore.Mvc.RazorPages;
+using Microsoft.AspNetCore.Mvc.RazorPages;
 using Microsoft.Extensions.DependencyInjection;
+using zero.Metadata;
 
 namespace zero.Mvc;
 
@@ -17,4 +17,9 @@ public abstract class ZeroPageModel : PageModel
   /// </summary>
   public ILocalizer Localizer => _localizer ?? (_localizer = HttpContext?.RequestServices?.GetService<ILocalizer>());
   ILocalizer _localizer;
+
+  /// <summary>
+  /// Set metadata for this page
+  /// </summary>
+  public MetadataOptions Metadata { get; protected set; } = new();
 }

zero/ZeroBuilder.cs

@@ -4,6 +4,7 @@ using Microsoft.AspNetCore.Hosting;
 using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.DependencyInjection;
 using zero.Mails;
+using zero.Metadata;
 using zero.Mvc;
 using zero.Numbers;
 using zero.Routing;
@@ -60,6 +61,7 @@ public class ZeroBuilder
     Modules.Add<ZeroRenderingModule>();
     Modules.Add<ZeroNumberModule>();
     Modules.Add<ZeroRoutingModule>();
+    Modules.Add<ZeroMetadataModule>();
 
     Modules.ConfigureServices(services, configuration);