From 1c40c08924b2e0bc3987d213f7405aaa9807c867 Mon Sep 17 00:00:00 2001
From: alexandre-spieser <bl4ck_dr4g0n2004@hotmail.com>
Date: Sun, 27 Aug 2017 22:07:59 +0000
Subject: [PATCH] projection functionality

---
 IntegrationTests/IntegrationTests.csproj      |   1 +
 IntegrationTests/ProjectTests.cs              | 148 ++++++++++++++++++
 MongoDbGenericRepository/MongoDbRepository.cs | 112 ++++++++++++-
 3 files changed, 256 insertions(+), 5 deletions(-)
 create mode 100644 IntegrationTests/ProjectTests.cs

diff --git a/IntegrationTests/IntegrationTests.csproj b/IntegrationTests/IntegrationTests.csproj
index a3ec14a..81ca024 100644
--- a/IntegrationTests/IntegrationTests.csproj
+++ b/IntegrationTests/IntegrationTests.csproj
@@ -63,6 +63,7 @@
     <Compile Include="Infrastructure\ITestRepository.cs" />
     <Compile Include="Infrastructure\TestRepository.cs" />
     <Compile Include="CreateTests.cs" />
+    <Compile Include="ProjectTests.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
     <Compile Include="ReadPartitionedTests.cs" />
     <Compile Include="ReadTests.cs" />
diff --git a/IntegrationTests/ProjectTests.cs b/IntegrationTests/ProjectTests.cs
new file mode 100644
index 0000000..971fd22
--- /dev/null
+++ b/IntegrationTests/ProjectTests.cs
@@ -0,0 +1,148 @@
+using IntegrationTests.Infrastructure;
+using MongoDbGenericRepository.Models;
+using NUnit.Framework;
+using System;
+using System.Linq;
+using System.Threading.Tasks;
+
+namespace IntegrationTests
+{
+    public class Nested
+    {
+        public DateTime SomeDate { get; set; }
+
+    }
+
+    public class ProjectTestsDocument : Document
+    {
+        public ProjectTestsDocument()
+        {
+            Version = 2;
+            Nested = new Nested
+            {
+                SomeDate = DateTime.UtcNow
+            };
+        }
+
+        public string SomeContent { get; set; }
+
+        public Nested Nested { get; set; }
+    }
+
+    public class ProjectTests : BaseMongoDbRepositoryTests<ProjectTestsDocument>
+    {
+        private class MyProjection
+        {
+            public DateTime SomeDate { get; set; }
+            public string SomeContent { get; set; }
+        }
+
+        [Test]
+        public async Task ProjectOneAsync()
+        {
+            // Arrange
+            const string someContent = "ProjectOneAsyncContent";
+            var someDate = DateTime.UtcNow;
+            var document = CreateTestDocument();
+            document.SomeContent = someContent;
+            document.Nested.SomeDate = someDate;
+            SUT.AddOne(document);
+            // Act
+            var result = await SUT.ProjectOneAsync<ProjectTestsDocument, MyProjection>(
+                x => x.Id == document.Id, 
+                x => new MyProjection
+                {
+                    SomeContent = x.SomeContent,
+                    SomeDate = x.Nested.SomeDate
+                });
+            // Assert
+            Assert.IsNotNull(result);
+            Assert.AreEqual(someContent, result.SomeContent);
+            Assert.AreEqual(someDate.Minute, result.SomeDate.Minute);
+            Assert.AreEqual(someDate.Second, result.SomeDate.Second);
+        }
+
+        [Test]
+        public void ProjectOne()
+        {
+            // Arrange
+            const string someContent = "ProjectOneContent";
+            var someDate = DateTime.UtcNow;
+            var document = CreateTestDocument();
+            document.SomeContent = someContent;
+            document.Nested.SomeDate = someDate;
+            SUT.AddOne(document);
+            // Act
+            var result = SUT.ProjectOne<ProjectTestsDocument, MyProjection>(
+                x => x.Id == document.Id,
+                x => new MyProjection
+                {
+                    SomeContent = x.SomeContent,
+                    SomeDate = x.Nested.SomeDate
+                });
+            // Assert
+            Assert.IsNotNull(result);
+            Assert.AreEqual(someContent, result.SomeContent);
+            Assert.AreEqual(someDate.Minute, result.SomeDate.Minute);
+            Assert.AreEqual(someDate.Second, result.SomeDate.Second);
+        }
+
+        [Test]
+        public async Task ProjectManyAsync()
+        {
+            // Arrange
+            const string someContent = "ProjectManyAsyncContent";
+            var someDate = DateTime.UtcNow;
+            var document = CreateTestDocuments(5);
+            document.ForEach(e =>
+            {
+                e.SomeContent = someContent;
+                e.Nested.SomeDate = someDate;
+            });
+
+            SUT.AddMany(document);
+            // Act
+            var result = await SUT.ProjectManyAsync<ProjectTestsDocument, MyProjection>(
+                x => x.SomeContent == someContent,
+                x => new MyProjection
+                {
+                    SomeContent = x.SomeContent,
+                    SomeDate = x.Nested.SomeDate
+                });
+            // Assert
+            Assert.AreEqual(5, result.Count);
+            Assert.AreEqual(someContent, result.First().SomeContent);
+            Assert.AreEqual(someDate.Minute, result.First().SomeDate.Minute);
+            Assert.AreEqual(someDate.Second, result.First().SomeDate.Second);
+        }
+
+        [Test]
+        public void ProjectMany()
+        {
+            // Arrange
+            const string someContent = "ProjectManyContent";
+            var someDate = DateTime.UtcNow;
+            var document = CreateTestDocuments(5);
+            document.ForEach(e =>
+            {
+                e.SomeContent = someContent;
+                e.Nested.SomeDate = someDate;
+            });
+
+            SUT.AddMany(document);
+            // Act
+            var result = SUT.ProjectMany<ProjectTestsDocument, MyProjection>(
+                x => x.SomeContent == someContent,
+                x => new MyProjection
+                {
+                    SomeContent = x.SomeContent,
+                    SomeDate = x.Nested.SomeDate
+                });
+            // Assert
+            Assert.AreEqual(5, result.Count);
+            Assert.AreEqual(someContent, result.First().SomeContent);
+            Assert.AreEqual(someDate.Minute, result.First().SomeDate.Minute);
+            Assert.AreEqual(someDate.Second, result.First().SomeDate.Second);
+        }
+    }
+}
diff --git a/MongoDbGenericRepository/MongoDbRepository.cs b/MongoDbGenericRepository/MongoDbRepository.cs
index f00ff93..ba44ee4 100644
--- a/MongoDbGenericRepository/MongoDbRepository.cs
+++ b/MongoDbGenericRepository/MongoDbRepository.cs
@@ -227,6 +227,58 @@ namespace MongoDbGenericRepository
 
         #endregion
 
+        #region Project
+
+        /// <summary>
+        /// Asynchronously returns a projected document matching the filter condition.
+        /// </summary>
+        /// <typeparam name="TDocument"></typeparam>
+        /// <typeparam name="TProjection"></typeparam>
+        /// <param name="filter"></param>
+        /// <param name="projection">The projection expression.</param>
+        /// <param name="partitionKey">An optional partition key.</param>
+        Task<TProjection> ProjectOneAsync<TDocument, TProjection>(Expression<Func<TDocument, bool>> filter, Expression<Func<TDocument, TProjection>> projection, string partitionKey = null)
+                                        where TDocument : IDocument
+                                        where TProjection : class;
+
+        /// <summary>
+        /// Returns a projected document matching the filter condition.
+        /// </summary>
+        /// <typeparam name="TDocument"></typeparam>
+        /// <typeparam name="TProjection"></typeparam>
+        /// <param name="filter"></param>
+        /// <param name="projection">The projection expression.</param>
+        /// <param name="partitionKey">An optional partition key.</param>
+        TProjection ProjectOne<TDocument, TProjection>(Expression<Func<TDocument, bool>> filter, Expression<Func<TDocument, TProjection>> projection, string partitionKey = null)
+                                        where TDocument : IDocument
+                                        where TProjection : class;
+
+        /// <summary>
+        /// Asynchronously returns a list of projected documents matching the filter condition.
+        /// </summary>
+        /// <typeparam name="TDocument"></typeparam>
+        /// <typeparam name="TProjection"></typeparam>
+        /// <param name="filter"></param>
+        /// <param name="projection">The projection expression.</param>
+        /// <param name="partitionKey">An optional partition key.</param>
+        Task<List<TProjection>> ProjectManyAsync<TDocument, TProjection>(Expression<Func<TDocument, bool>> filter, Expression<Func<TDocument, TProjection>> projection, string partitionKey = null)
+                                        where TDocument : IDocument
+                                        where TProjection : class;
+
+        /// <summary>
+        /// Asynchronously returns a list of projected documents matching the filter condition.
+        /// </summary>
+        /// <typeparam name="TDocument"></typeparam>
+        /// <typeparam name="TProjection"></typeparam>
+        /// <param name="filter"></param>
+        /// <param name="projection">The projection expression.</param>
+        /// <param name="partitionKey">An optional partition key.</param>
+        List<TProjection> ProjectMany<TDocument, TProjection>(Expression<Func<TDocument, bool>> filter, Expression<Func<TDocument, TProjection>> projection, string partitionKey = null)
+                                        where TDocument : IDocument
+                                        where TProjection : class;
+
+        #endregion
+
     }
 
     /// <summary>
@@ -577,27 +629,77 @@ namespace MongoDbGenericRepository
 
         #endregion Delete
 
-        #region Projection
+        #region Project
 
         /// <summary>
-        /// Asynchronously returns a list of projected document matching the filter condition.
+        /// Asynchronously returns a projected document matching the filter condition.
         /// </summary>
         /// <typeparam name="TDocument"></typeparam>
         /// <typeparam name="TProjection"></typeparam>
         /// <param name="filter"></param>
         /// <param name="projection">The projection expression.</param>
         /// <param name="partitionKey">An optional partition key.</param>
-        public async Task<TProjection> GetProjectedAsync<TDocument, TProjection>(Expression<Func<TDocument, bool>> filter, Expression<Func<TDocument, TProjection>> projection, string partitionKey = null)
+        public async Task<TProjection> ProjectOneAsync<TDocument, TProjection>(Expression<Func<TDocument, bool>> filter, Expression<Func<TDocument, TProjection>> projection, string partitionKey = null)
             where TDocument : IDocument
-            where TProjection : class, new()
+            where TProjection : class
         {
             return await HandlePartitioned<TDocument>(partitionKey).Find(filter)
                                                                    .Project(projection)
                                                                    .FirstOrDefaultAsync();
         }
 
-        #endregion
+        /// <summary>
+        /// Returns a projected document matching the filter condition.
+        /// </summary>
+        /// <typeparam name="TDocument"></typeparam>
+        /// <typeparam name="TProjection"></typeparam>
+        /// <param name="filter"></param>
+        /// <param name="projection">The projection expression.</param>
+        /// <param name="partitionKey">An optional partition key.</param>
+        public TProjection ProjectOne<TDocument, TProjection>(Expression<Func<TDocument, bool>> filter, Expression<Func<TDocument, TProjection>> projection, string partitionKey = null)
+            where TDocument : IDocument
+            where TProjection : class
+        {
+            return HandlePartitioned<TDocument>(partitionKey).Find(filter)
+                                                             .Project(projection)
+                                                             .FirstOrDefault();
+        }
 
+        /// <summary>
+        /// Asynchronously returns a list of projected documents matching the filter condition.
+        /// </summary>
+        /// <typeparam name="TDocument"></typeparam>
+        /// <typeparam name="TProjection"></typeparam>
+        /// <param name="filter"></param>
+        /// <param name="projection">The projection expression.</param>
+        /// <param name="partitionKey">An optional partition key.</param>
+        public async Task<List<TProjection>> ProjectManyAsync<TDocument, TProjection>(Expression<Func<TDocument, bool>> filter, Expression<Func<TDocument, TProjection>> projection, string partitionKey = null)
+            where TDocument : IDocument
+            where TProjection : class
+        {
+            return await HandlePartitioned<TDocument>(partitionKey).Find(filter)
+                                                                   .Project(projection)
+                                                                   .ToListAsync();
+        }
+
+        /// <summary>
+        /// Asynchronously returns a list of projected documents matching the filter condition.
+        /// </summary>
+        /// <typeparam name="TDocument"></typeparam>
+        /// <typeparam name="TProjection"></typeparam>
+        /// <param name="filter"></param>
+        /// <param name="projection">The projection expression.</param>
+        /// <param name="partitionKey">An optional partition key.</param>
+        public List<TProjection> ProjectMany<TDocument, TProjection>(Expression<Func<TDocument, bool>> filter, Expression<Func<TDocument, TProjection>> projection, string partitionKey = null)
+            where TDocument : IDocument
+            where TProjection : class
+        {
+            return HandlePartitioned<TDocument>(partitionKey).Find(filter)
+                                                             .Project(projection)
+                                                             .ToList();
+        }
+
+        #endregion
 
         /// <summary>
         /// Asynchronously returns a paginated list of the documents matching the filter condition.