Move culture fallback logic to the TemplateContentProvider

framework/src/Volo.Abp.TextTemplating/Volo/Abp/TextTemplating/ITemplateContentProvider.cs

@@ -7,12 +7,14 @@ namespace Volo.Abp.TextTemplating
     {
         Task<string> GetContentOrNullAsync(
             [NotNull] string templateName,
-            [CanBeNull] string cultureName = null
+            [CanBeNull] string cultureName = null,
+            bool tryDefaults = true
         );
 
         Task<string> GetContentOrNullAsync(
             [NotNull] TemplateDefinition templateDefinition,
-            [CanBeNull] string cultureName = null
+            [CanBeNull] string cultureName = null,
+            bool tryDefaults = true
         );
     }
 }

framework/src/Volo.Abp.TextTemplating/Volo/Abp/TextTemplating/TemplateContentContributorContext.cs

@@ -11,17 +11,17 @@ namespace Volo.Abp.TextTemplating
         [NotNull]
         public IServiceProvider ServiceProvider { get; }
 
-        [CanBeNull]
+        [NotNull]
         public string Culture { get; }
 
         public TemplateContentContributorContext(
             [NotNull] TemplateDefinition templateDefinition,
             [NotNull] IServiceProvider serviceProvider, 
-            [CanBeNull] string culture)
+            [NotNull] string culture)
         {
             TemplateDefinition = Check.NotNull(templateDefinition, nameof(templateDefinition));
             ServiceProvider = Check.NotNull(serviceProvider, nameof(serviceProvider));
-            Culture = culture;
+            Culture = Check.NotNull(culture, nameof(culture));
         }
     }
 }

framework/src/Volo.Abp.TextTemplating/Volo/Abp/TextTemplating/TemplateContentProvider.cs

@@ -1,9 +1,11 @@
-using System.Linq;
+using System.Globalization;
+using System.Linq;
 using System.Threading.Tasks;
 using JetBrains.Annotations;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Options;
 using Volo.Abp.DependencyInjection;
+using Volo.Abp.Localization;
 
 namespace Volo.Abp.TextTemplating
 {
@@ -23,17 +25,19 @@ namespace Volo.Abp.TextTemplating
             _templateDefinitionManager = templateDefinitionManager;
         }
 
-        public Task<string> GetContentOrNullAsync(
+        public virtual Task<string> GetContentOrNullAsync(
             [NotNull] string templateName, 
-            [CanBeNull] string cultureName = null)
+            [CanBeNull] string cultureName = null,
+            bool tryDefaults = true)
         {
             var template = _templateDefinitionManager.Get(templateName);
             return GetContentOrNullAsync(template, cultureName);
         }
 
-        public async Task<string> GetContentOrNullAsync(
+        public virtual async Task<string> GetContentOrNullAsync(
             [NotNull] TemplateDefinition templateDefinition,
-            [CanBeNull] string cultureName = null)
+            [CanBeNull] string cultureName = null,
+            bool tryDefaults = true)
         {
             Check.NotNull(templateDefinition, nameof(templateDefinition));
 
@@ -44,30 +48,93 @@ namespace Volo.Abp.TextTemplating
                 );
             }
 
+            if (cultureName == null)
+            {
+                cultureName = CultureInfo.CurrentUICulture.Name;
+            }
+
             using (var scope = ServiceScopeFactory.CreateScope())
             {
-                var context = new TemplateContentContributorContext(
-                    templateDefinition,
-                    scope.ServiceProvider,
-                    cultureName
+                var contributors = Options.ContentContributors
+                    .Select(type => (ITemplateContentContributor) scope.ServiceProvider.GetRequiredService(type))
+                    .Reverse()
+                    .ToArray();
+
+                //Try to get from the requested culture
+                var templateString = await GetContentOrNullAsync(
+                    contributors,
+                    new TemplateContentContributorContext(
+                        templateDefinition,
+                        scope.ServiceProvider,
+                        cultureName
+                    )
                 );
 
-                foreach (var contentContributorType in Options.ContentContributors.Reverse())
+                if (templateString != null)
+                {
+                    return templateString;
+                }
+
+                if (!tryDefaults)
                 {
-                    var contributor = (ITemplateContentContributor) scope.ServiceProvider
-                            .GetRequiredService(contentContributorType);
+                    return null;
+                }
+
+                //Try to get from same culture without country code
+                if (cultureName.Contains("-")) //Example: "tr-TR"
+                {
+                    templateString = await GetContentOrNullAsync(
+                        contributors,
+                        new TemplateContentContributorContext(
+                            templateDefinition,
+                            scope.ServiceProvider,
+                            CultureHelper.GetBaseCultureName(cultureName)
+                        )
+                    );
+
+                    if (templateString != null)
+                    {
+                        return templateString;
+                    }
+                }
+
+                //Try to get from default culture
+                if (templateDefinition.DefaultCultureName != null)
+                {
+                    templateString = await GetContentOrNullAsync(
+                        contributors,
+                        new TemplateContentContributorContext(
+                            templateDefinition,
+                            scope.ServiceProvider,
+                            templateDefinition.DefaultCultureName
+                        )
+                    );
 
-                    var templateString = await contributor.GetOrNullAsync(context);
                     if (templateString != null)
                     {
                         return templateString;
                     }
                 }
             }
-            
-            throw new AbpException(
-                $"None of the template content contributors could get the content for the template '{templateDefinition.Name}'"
-            );
+
+            //Not found
+            return null;
+        }
+
+        protected virtual async Task<string> GetContentOrNullAsync(
+            ITemplateContentContributor[] contributors,
+            TemplateContentContributorContext context)
+        {
+            foreach (var contributor in contributors)
+            {
+                var templateString = await contributor.GetOrNullAsync(context);
+                if (templateString != null)
+                {
+                    return templateString;
+                }
+            }
+
+            return null;
         }
     }
 }

framework/src/Volo.Abp.TextTemplating/Volo/Abp/TextTemplating/VirtualFiles/FileInfoLocalizedTemplateContentReader.cs

@@ -12,7 +12,7 @@ namespace Volo.Abp.TextTemplating.VirtualFiles
             _content = await fileInfo.ReadAsStringAsync();
         }
 
-        public string GetContent(string culture, string defaultCultureName)
+        public string GetContentOrNull(string culture)
         {
             return _content;
         }

framework/src/Volo.Abp.TextTemplating/Volo/Abp/TextTemplating/VirtualFiles/ILocalizedTemplateContentReader.cs

@@ -2,6 +2,6 @@
 {
     public interface ILocalizedTemplateContentReader
     {
-        public string GetContent(string culture, string defaultCultureName = null);
+        public string GetContentOrNull(string culture);
     }
 }

framework/src/Volo.Abp.TextTemplating/Volo/Abp/TextTemplating/VirtualFiles/NullLocalizedTemplateContentReader.cs

@@ -9,9 +9,7 @@
             
         }
 
-        public string GetContent(
-            string culture,
-            string defaultCultureName = null)
+        public string GetContentOrNull(string culture)
         {
             return null;
         }

framework/src/Volo.Abp.TextTemplating/Volo/Abp/TextTemplating/VirtualFiles/VirtualFileTemplateContentContributor.cs

@@ -21,9 +21,8 @@ namespace Volo.Abp.TextTemplating.VirtualFiles
             var localizedReader = await _localizedTemplateContentReaderFactory
                 .CreateAsync(context.TemplateDefinition);
 
-            return localizedReader.GetContent(
-                context.Culture ?? CultureInfo.CurrentUICulture.Name,
-                context.TemplateDefinition.DefaultCultureName
+            return localizedReader.GetContentOrNull(
+                context.Culture
             );
         }
     }

framework/src/Volo.Abp.TextTemplating/Volo/Abp/TextTemplating/VirtualFiles/VirtualFolderLocalizedTemplateContentReader.cs

@@ -2,7 +2,6 @@
 using System.Collections.Generic;
 using System.Threading.Tasks;
 using Microsoft.Extensions.FileProviders;
-using Volo.Abp.Localization;
 using Volo.Abp.VirtualFileSystem;
 
 namespace Volo.Abp.TextTemplating.VirtualFiles
@@ -34,34 +33,9 @@ namespace Volo.Abp.TextTemplating.VirtualFiles
             }
         }
 
-        public string GetContent(string cultureName, string defaultCultureName)
+        public string GetContentOrNull(string cultureName)
         {
-            var content = _dictionary.GetOrDefault(cultureName);
-            if (content != null)
-            {
-                return content;
-            }
-
-            if (cultureName.Contains("-"))
-            {
-                var baseCultureName = CultureHelper.GetBaseCultureName(cultureName);
-                content = _dictionary.GetOrDefault(baseCultureName);
-                if (content != null)
-                {
-                    return content;
-                }
-            }
-
-            if (defaultCultureName != null)
-            {
-                content = _dictionary.GetOrDefault(defaultCultureName);
-                if (content != null)
-                {
-                    return content;
-                }
-            }
-
-            return null;
+            return _dictionary.GetOrDefault(cultureName);
         }
     }
 }