Add SupportedCultures and DefaultCulture (#16968)

Co-authored-by: Hisham Bin Ateya <[email protected]>
OrchardCMS · Nov 8, 2024 · dbc81b8 · dbc81b8
1 parent 64e03ce
commit dbc81b8
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Showing 4 changed files with 75 additions and 18 deletions.
diff --git a/src/OrchardCore/OrchardCore.DisplayManagement.Liquid/Filters/SupportedCulturesFilter.cs b/src/OrchardCore/OrchardCore.DisplayManagement.Liquid/Filters/SupportedCulturesFilter.cs
@@ -6,6 +6,7 @@
 
 namespace OrchardCore.DisplayManagement.Liquid.Filters;
 
+[Obsolete("This filter is obsolete and will be removed in a future version. Use 'Culture.SupportedCultures' instead.")]
 public class SupportedCulturesFilter : ILiquidFilter
 {
     private readonly ILocalizationService _localizationService;

diff --git a/src/OrchardCore/OrchardCore.DisplayManagement.Liquid/OrchardCoreBuilderExtensions.cs b/src/OrchardCore/OrchardCore.DisplayManagement.Liquid/OrchardCoreBuilderExtensions.cs
@@ -48,6 +48,7 @@ public static OrchardCoreBuilder AddLiquidViews(this OrchardCoreBuilder builder)
             services.AddScoped<IRazorViewExtensionProvider, LiquidViewExtensionProvider>();
             services.AddSingleton<LiquidTagHelperFactory>();
 
+#pragma warning disable CS0618 // Type or member is obsolete
             services.Configure<TemplateOptions>(o =>
             {
                 o.ValueConverters.Add(x =>
@@ -67,7 +68,6 @@ public static OrchardCoreBuilder AddLiquidViews(this OrchardCoreBuilder builder)
                 o.MemberAccessStrategy.Register<Shape>("*", new ShapeAccessor());
                 o.MemberAccessStrategy.Register<ZoneHolding>("*", new ShapeAccessor());
                 o.MemberAccessStrategy.Register<ShapeMetadata>();
-                o.MemberAccessStrategy.Register<CultureInfo>();
 
                 o.Scope.SetValue("Culture", new CultureValue());
 
@@ -163,7 +163,10 @@ public static OrchardCoreBuilder AddLiquidViews(this OrchardCoreBuilder builder)
             .AddLiquidFilter<AppendVersionFilter>("append_version")
             .AddLiquidFilter<ResourceUrlFilter>("resource_url")
             .AddLiquidFilter<SanitizeHtmlFilter>("sanitize_html")
+
+            // Deprecated, remove in a future version.
             .AddLiquidFilter<SupportedCulturesFilter>("supported_cultures");
+#pragma warning restore CS0618 // Type or member is obsolete
         });
 
         return builder;

diff --git a/src/OrchardCore/OrchardCore.DisplayManagement.Liquid/Values/CultureValue.cs b/src/OrchardCore/OrchardCore.DisplayManagement.Liquid/Values/CultureValue.cs
@@ -2,14 +2,39 @@
 using System.Text.Encodings.Web;
 using Fluid;
 using Fluid.Values;
+using Microsoft.Extensions.DependencyInjection;
+using OrchardCore.Liquid;
 using OrchardCore.Localization;
 
 namespace OrchardCore.DisplayManagement.Liquid.Values;
 
 internal sealed class CultureValue : FluidValue
 {
+    // When null it means this is the global "Culture" object that represents the current UI culture.
+    private readonly CultureInfo _culture;
+
+    private CultureInfo Culture => _culture ?? CultureInfo.CurrentUICulture;
+
     public override FluidValues Type => FluidValues.Object;
 
+    /// <summary>
+    /// Creates a new instance of a <see cref="CultureValue"/> that uses <see cref="CultureInfo.CurrentUICulture"/> when resolved.
+    /// </summary>
+    public CultureValue()
+    {
+        _culture = null;
+    }
+
+    /// <summary>
+    /// Creates a new instance of a <see cref="CultureValue"/> for the specified culture.
+    /// </summary>
+    public CultureValue(CultureInfo culture)
+    {
+        ArgumentNullException.ThrowIfNull(culture);
+
+        _culture = culture;
+    }
+
     public override bool Equals(FluidValue other)
     {
         if (other is null)
@@ -24,26 +49,53 @@ public override bool Equals(FluidValue other)
 
     public override decimal ToNumberValue() => 0;
 
-    public override object ToObjectValue() => ToStringValue();
+    public override object ToObjectValue() => Culture;
 
-    public override string ToStringValue() => CultureInfo.CurrentUICulture.Name;
+    public override string ToStringValue() => Culture.Name;
 
 #pragma warning disable CS0672 // Member overrides obsolete member
     public override void WriteTo(TextWriter writer, TextEncoder encoder, CultureInfo cultureInfo)
 #pragma warning restore CS0672 // Member overrides obsolete member
-        => writer.Write(ToStringValue());
+        => writer.Write(Culture.Name);
 
     public async override ValueTask WriteToAsync(TextWriter writer, TextEncoder encoder, CultureInfo cultureInfo)
-        => await writer.WriteAsync(CultureInfo.CurrentUICulture.Name);
+        => await writer.WriteAsync(Culture.Name);
 
-    protected override FluidValue GetValue(string name, TemplateContext context)
-        => name switch
+    public override ValueTask<FluidValue> GetValueAsync(string name, TemplateContext context)
+    {
+        return name switch
         {
-            nameof(CultureInfo.Name) => new StringValue(CultureInfo.CurrentUICulture.Name),
-            "Dir" => new StringValue(CultureInfo.CurrentUICulture.GetLanguageDirection()),
-            nameof(CultureInfo.NativeName) => new StringValue(CultureInfo.CurrentUICulture.NativeName),
-            nameof(CultureInfo.DisplayName) => new StringValue(CultureInfo.CurrentUICulture.DisplayName),
-            nameof(CultureInfo.TwoLetterISOLanguageName) => new StringValue(CultureInfo.CurrentUICulture.TwoLetterISOLanguageName),
-            _ => NilValue.Instance
+            nameof(CultureInfo.Name) => ValueTask.FromResult<FluidValue>(new StringValue(Culture.Name)),
+            nameof(CultureInfo.NativeName) => ValueTask.FromResult<FluidValue>(new StringValue(Culture.NativeName)),
+            nameof(CultureInfo.DisplayName) => ValueTask.FromResult<FluidValue>(new StringValue(Culture.DisplayName)),
+            nameof(CultureInfo.TwoLetterISOLanguageName) => ValueTask.FromResult<FluidValue>(new StringValue(Culture.TwoLetterISOLanguageName)),
+            "Dir" => ValueTask.FromResult<FluidValue>(new StringValue(Culture.GetLanguageDirection())),
+            "SupportedCultures" => _culture is null ? GetSupportedCulturesAsync(context) : ValueTask.FromResult<FluidValue>(NilValue.Instance),
+            "DefaultCulture" => _culture is null ? GetDefaultCultureAsync(context) : ValueTask.FromResult<FluidValue>(NilValue.Instance),
+            _ => ValueTask.FromResult<FluidValue>(NilValue.Instance)
         };
+    }
+
+    private static async ValueTask<FluidValue> GetSupportedCulturesAsync(TemplateContext context)
+    {
+        var ctx = context as LiquidTemplateContext
+            ?? throw new InvalidOperationException($"An implementation of '{nameof(LiquidTemplateContext)}' is required");
+
+        var services = ctx.Services;
+        var localizationService = services.GetRequiredService<ILocalizationService>();
+        var supportedCultures = await localizationService.GetSupportedCulturesAsync();
+
+        return new ArrayValue(supportedCultures.Select(c => new CultureValue(CultureInfo.GetCultureInfo(c))).ToArray());
+    }
+
+    private static async ValueTask<FluidValue> GetDefaultCultureAsync(TemplateContext context)
+    {
+        var ctx = context as LiquidTemplateContext
+            ?? throw new InvalidOperationException($"An implementation of '{nameof(LiquidTemplateContext)}' is required");
+
+        var services = ctx.Services;
+        var localizationService = services.GetRequiredService<ILocalizationService>();
+
+        return new CultureValue(CultureInfo.GetCultureInfo(await localizationService.GetDefaultCultureAsync()));
+    }
 }
diff --git a/src/docs/reference/modules/Liquid/README.md b/src/docs/reference/modules/Liquid/README.md
@@ -509,16 +509,17 @@ The following properties are available on the `Culture` object.
 | `DisplayName` | `English (United States)` | The display name of the current culture. |
 | `NativeName` | `English (United States)` | The native name of the current culture. |
 | `TwoLetterISOLanguageName` | `en` | The two-letter ISO language name of the current culture. |
+| `SupportedCultures` | `['en-US', 'fr' ]` | The list of the currently supported cultures in the site. Each result can be chained with other properties listed in this table. |
+| `DefaultCulture` | `en-US` | The default culture as defined in the settings. |
 
-##### supported_cultures filter
+##### Usage
 
-Returns the currently supported cultures. Here is an example of how to print the names of supported cultures using a list:
+Here is an example of how to print the names of supported cultures and find which one is currently used:
 
 ```liquid
-{% assign cultures = Culture | supported_cultures %}
 <ul>
-{% for culture in cultures %}
-    <li>{{ culture.Name }}</li>
+{% for culture in Culture.SupportedCultures %}
+    <li class="{% if culture == Culture %}active{% endif %}">{{ culture.Name }}</li>
 {% endfor %}
 </ul>
 ```