Use generic repository pattern and include tag search page

Author: linkdotnet

LinkDotNet.Blog.Web/Pages/Index.razor

@@ -17,7 +17,7 @@
     IList<BlogPost> _blogPosts = new List<BlogPost>();
     protected override async Task OnInitializedAsync()
     {
-        _blogPosts = (await _repository.GetAllAsync()).OrderByDescending(o => o.UpdatedDate).ToList();
+        _blogPosts = (await _repository.GetAllAsync(orderBy: b => b.UpdatedDate)).ToList();
     }
 
 }

LinkDotNet.Blog.Web/Pages/SearchByTag.razor

@@ -0,0 +1,22 @@
+@page "/searchByTag/{tag}"
+@using LinkDotNet.Domain
+@using LinkDotNet.Infrastructure.Persistence
+@inject IRepository _repository
+
+<h3>All posts with Tag <em>@Tag</em></h3>
+
+@for (var i = 0; i < _blogPosts.Count; i++)
+    {
+        <ShortBlogPost BlogPost="_blogPosts[i]" UseAlternativeStyle="@(i % 2 != 0)"></ShortBlogPost>
+    }
+
+@code {
+    [Parameter]
+    public string Tag { get; set; }
+    
+    IList<BlogPost> _blogPosts = new List<BlogPost>();
+    protected override async Task OnInitializedAsync()
+    {
+        _blogPosts = (await _repository.GetAllAsync(b => b.Tags.Any(t => t.Content == Tag), b => b.UpdatedDate)).ToList();
+    }
+}

LinkDotNet.Blog.Web/Shared/ShortBlogPost.razor

@@ -12,7 +12,7 @@
           <ul>
             @foreach (var tag in BlogPost.Tags.Select(t => t.Content))
             {
-              <li><a href="#">@tag</a></li>
+              <li><a href="/searchByTag/@tag">@tag</a></li>
             }
           </ul>
         </li>

LinkDotNet.Infrastructure/Persistence/IRepository.cs

@@ -1,4 +1,6 @@
-using System.Collections.Generic;
+using System;
+using System.Collections.Generic;
+using System.Linq.Expressions;
 using System.Threading.Tasks;
 using LinkDotNet.Domain;
 
@@ -8,7 +10,7 @@ public interface IRepository
     {
         Task<BlogPost> GetByIdAsync(string blogPostId);
 
-        Task<IEnumerable<BlogPost>> GetAllAsync();
+        Task<IEnumerable<BlogPost>> GetAllAsync(Expression<Func<BlogPost, bool>> filter = null, Expression<Func<BlogPost, object>> orderBy = null, bool descending = true);
 
         Task StoreAsync(BlogPost blogPost);
     }

LinkDotNet.Infrastructure/Persistence/InMemory/InMemoryRepository.cs

@@ -1,5 +1,7 @@
-using System.Collections.Generic;
+using System;
+using System.Collections.Generic;
 using System.Linq;
+using System.Linq.Expressions;
 using System.Threading.Tasks;
 using LinkDotNet.Domain;
 
@@ -15,8 +17,24 @@ public Task<BlogPost> GetByIdAsync(string blogPostId)
             return Task.FromResult(blogPost);
         }
 
-        public Task<IEnumerable<BlogPost>> GetAllAsync()
+        public Task<IEnumerable<BlogPost>> GetAllAsync(Expression<Func<BlogPost, bool>> filter = null, Expression<Func<BlogPost, object>> orderBy = null, bool descending = true)
         {
+            var result = blogPosts.AsEnumerable();
+            if (filter != null)
+            {
+                result = result.Where(filter.Compile());
+            }
+
+            if (orderBy != null)
+            {
+                if (descending)
+                {
+                    return Task.FromResult(result.OrderByDescending(orderBy.Compile()).AsEnumerable());
+                }
+
+                return Task.FromResult(result.OrderBy(orderBy.Compile()).AsEnumerable());
+            }
+
             return Task.FromResult(blogPosts.AsEnumerable());
         }
 

LinkDotNet.Infrastructure/Persistence/RavenDb/BlogPostRepository.cs

@@ -1,7 +1,10 @@
+using System;
 using System.Collections.Generic;
+using System.Linq.Expressions;
 using System.Threading.Tasks;
 using LinkDotNet.Domain;
 using Raven.Client.Documents;
+using Raven.Client.Documents.Linq;
 
 namespace LinkDotNet.Infrastructure.Persistence.RavenDb
 {
@@ -20,10 +23,27 @@ public async Task<BlogPost> GetByIdAsync(string blogPostId)
             return await session.LoadAsync<BlogPost>(blogPostId);
         }
 
-        public async Task<IEnumerable<BlogPost>> GetAllAsync()
+        public async Task<IEnumerable<BlogPost>> GetAllAsync(Expression<Func<BlogPost, bool>> filter = null, Expression<Func<BlogPost, object>> orderBy = null, bool descending = true)
         {
             using var session = documentStore.OpenAsyncSession();
-            return await session.Query<BlogPost>().ToListAsync();
+
+            var query = session.Query<BlogPost>();
+            if (filter != null)
+            {
+                query = query.Where(filter);
+            }
+
+            if (orderBy != null)
+            {
+                if (descending)
+                {
+                    return await query.OrderByDescending(orderBy).ToListAsync();
+                }
+
+                return await query.OrderBy(orderBy).ToListAsync();
+            }
+
+            return await query.ToListAsync();
         }
 
         public async Task StoreAsync(BlogPost blogPost)

LinkDotNet.Infrastructure/Persistence/Sql/BlogPostRepository.cs

@@ -1,4 +1,7 @@
-using System.Collections.Generic;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Linq.Expressions;
 using System.Threading.Tasks;
 using LinkDotNet.Domain;
 using Microsoft.EntityFrameworkCore;
@@ -16,12 +19,29 @@ public BlogPostRepository(BlogPostContext blogPostContext)
 
         public async Task<BlogPost> GetByIdAsync(string blogPostId)
         {
-            return await blogPostContext.BlogPosts.SingleAsync(b => b.Id == blogPostId);
+            return await blogPostContext.BlogPosts.Include(b => b.Tags).SingleAsync(b => b.Id == blogPostId);
         }
 
-        public async Task<IEnumerable<BlogPost>> GetAllAsync()
+        public async Task<IEnumerable<BlogPost>> GetAllAsync(Expression<Func<BlogPost, bool>> filter = null, Expression<Func<BlogPost, object>> orderBy = null, bool descending = true)
         {
-            return await blogPostContext.BlogPosts.ToListAsync();
+            var blogPosts = blogPostContext.BlogPosts.Include(b => b.Tags).AsQueryable();
+
+            if (filter != null)
+            {
+                blogPosts = blogPosts.Where(filter);
+            }
+
+            if (orderBy != null)
+            {
+                if (descending)
+                {
+                    return await blogPosts.OrderByDescending(orderBy).ToListAsync();
+                }
+
+                return await blogPosts.OrderBy(orderBy).ToListAsync();
+            }
+
+            return await blogPosts.ToListAsync();
         }
 
         public async Task StoreAsync(BlogPost blogPost)