Added fluent ComponentRenderer type - fixes #12

conficient · Apr 18, 2021 · 5ae7103 · 5ae7103
1 parent 040e8b2
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Showing 7 changed files with 530 additions and 12 deletions.
diff --git a/BlazorTemplater.Tests/ComponentRenderer_Tests.cs b/BlazorTemplater.Tests/ComponentRenderer_Tests.cs
@@ -0,0 +1,211 @@
+using BlazorTemplater.Library;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+using System;
+
+namespace BlazorTemplater.Tests
+{
+    /// <summary>
+    ///
+    /// </summary>
+    [TestClass]
+    public class ComponentRenderer_Tests
+    {
+        [TestMethod]
+        public void Ctor_Test()
+        {
+            var builder = new ComponentRenderer<Simple>();
+
+            Assert.IsNotNull(builder);
+        }
+
+        #region Simple render
+
+        /// <summary>
+        /// Render a component (no service injection or parameters)
+        /// </summary>
+        [TestMethod]
+        public void Simple_Test()
+        {
+            const string expected = @"<b>Jan 1st is 2021-01-01</b>";
+            var actual = new ComponentRenderer<Simple>()
+                .Render();
+
+            Console.WriteLine(actual);
+            Assert.AreEqual(expected, actual);
+        }
+
+        #endregion Simple render
+
+        #region Parameters
+
+        /// <summary>
+        /// Test a component with a parameter
+        /// </summary>
+        [TestMethod]
+        public void ComponentBuilder_Parameters_Test()
+        {
+            // expected output
+            const string expected = "<p>Steve Sanderson is awesome!</p>";
+
+            var model = new TestModel()
+            {
+                Name = "Steve Sanderson",
+                Description = "is awesome"
+            };
+
+            var html = new ComponentRenderer<Parameters>()
+                .Set(c => c.Model, model)
+                .Render();
+
+            // trim leading space and trailing CRLF from output
+            var actual = html.Trim();
+
+            Console.WriteLine(actual);
+            Assert.AreEqual(expected, actual);
+        }
+
+        /// <summary>
+        /// Test a component with a parameter
+        /// </summary>
+        [TestMethod]
+        public void ComponentBuilder_Parameters_TestHtmlEncoding()
+        {
+            // expected output
+            const string expected = "<p>Safia &amp; Pranav are awesome too!</p>";
+
+            var templater = new Templater();
+            var model = new TestModel()
+            {
+                Name = "Safia & Pranav",    // the text here is HTML encoded
+                Description = "are awesome too"
+            };
+            var html = new ComponentRenderer<Parameters>()
+                .Set(c => c.Model, model)
+                .Render();
+
+            // trim leading space and trailing CRLF from output
+            var actual = html.Trim();
+
+            Console.WriteLine(actual);
+            Assert.AreEqual(expected, actual);
+        }
+
+        /// <summary>
+        /// Test a component with a parameter which isn't set
+        /// </summary>
+        [TestMethod]
+        public void ComponentBuilder_Parameters_TestIfModelNotSet()
+        {
+            // expected output
+            const string expected = "<p>No model!</p>";
+
+            var html = new ComponentRenderer<Parameters>()
+                .Render();
+
+            // trim leading space and trailing CRLF from output
+            var actual = html.Trim();
+
+            Console.WriteLine(actual);
+            Assert.AreEqual(expected, actual);
+        }
+
+        #endregion Parameters
+
+        #region Errors
+
+        /// <summary>
+        /// Test rendering model with error (null reference is expected)
+        /// </summary>
+        [TestMethod]
+        public void ComponentRenderer_Error_Test()
+        {
+            var templater = new Templater();
+
+            // we should get a NullReferenceException thrown as Model parameter is not set
+            Assert.ThrowsException<NullReferenceException>(() =>
+            {
+                _ = new ComponentRenderer<ErrorTest>().Render();
+            });
+        }
+
+        #endregion Errors
+
+        #region Dependency Injection
+
+        [TestMethod]
+        public void AddService_Test()
+        {
+            // set up
+            const int a = 2;
+            const int b = 3;
+            const int c = a + b;
+            string expected = $"<p>If you add {a} and {b} you get {c}</p>";
+
+            // fluent ComponentBuilder approach
+            var actual = new ComponentRenderer<ServiceInjection>()
+                .AddService<ITestService>(new TestService())
+                .Set(p => p.A, a)
+                .Set(p => p.B, b)
+                .Render();
+
+            Console.WriteLine(actual);
+            Assert.AreEqual(expected, actual);
+        }
+
+        #endregion
+
+        #region Nesting
+
+        /// <summary>
+        /// Test that a component containing other components render correctly
+        /// </summary>
+        [TestMethod]
+        public void ComponentRenderer_Nested_Test()
+        {
+            // expected output
+            // the spaces before the <p> come from the Parameters.razor component
+            // on Windows the string contains \r\n and on unix it's just \n
+            string expected = $"<b>Jan 1st is 2021-01-01</b>{Environment.NewLine}    <p>Dan Roth is cool!</p>";
+
+            var templater = new Templater();
+            var model = new TestModel()
+            {
+                Name = "Dan Roth",
+                Description = "is cool"
+            };
+            var html = new ComponentRenderer<NestedComponents>()
+                .Set(c => c.Model, model)
+                .Render();
+
+            // trim leading space and trailing CRLF from output
+            var actual = html.Trim();
+
+            Console.WriteLine(actual);
+            Assert.AreEqual(expected, actual);
+        }
+
+        #endregion
+
+        #region Cascading Values
+
+        [TestMethod]
+        public void ComponentRenderer_CascadingValues_Test()
+        {
+            const string expected = "<p>The name is Bill</p>";
+            var info = new CascadeInfo() { Name = "Bill" };
+
+            var html = new ComponentRenderer<CascadeParent>()
+                .Set(c => c.Info, info)
+                .Render();
+
+            // trim leading space and trailing CRLF from output
+            var actual = html.Trim();
+
+            Assert.AreEqual(expected, actual);
+
+        }
+
+        #endregion
+
+    }
+}
diff --git a/BlazorTemplater/BlazorTemplater.csproj b/BlazorTemplater/BlazorTemplater.csproj
@@ -11,6 +11,7 @@
     <PackageTags>Blazor RazorComponents HTML Email Templating</PackageTags>
     <Version>1.2.0</Version>
     <PackageReleaseNotes>Fixed issue with using library in .NET 5.0</PackageReleaseNotes>
+    <LangVersion>Latest</LangVersion>
   </PropertyGroup>
 
   <ItemGroup>

diff --git a/BlazorTemplater/ComponentRenderer.cs b/BlazorTemplater/ComponentRenderer.cs
@@ -0,0 +1,127 @@
+using Microsoft.AspNetCore.Components;
+using System;
+using System.Collections.Generic;
+using System.Linq.Expressions;
+using System.Reflection;
+
+namespace BlazorTemplater
+{
+    /*
+     * Adapted from ParameterViewBuilder.cs in Egil Hansen's Genzor
+     * https://github.com/egil/genzor/blob/main/src/genzor/ParameterViewBuilder.cs
+     * Thanks for the suggestion, Egil!
+     */
+
+    /// <summary>
+    /// Fluent component renderer
+    /// </summary>
+    /// <typeparam name="TComponent">Type of component to render</typeparam>
+    public class ComponentRenderer<TComponent> where TComponent : IComponent
+    {
+        private const string ChildContent = nameof(ChildContent);
+        private static readonly Type TComponentType = typeof(TComponent);
+
+        private readonly Dictionary<string, object> parameters = new(StringComparer.Ordinal);
+        private readonly Templater templater;
+
+        #region Ctor
+
+        /// <summary>
+        /// Create a new renderer
+        /// </summary>
+        public ComponentRenderer()
+        {
+            templater = new Templater();
+        }
+
+        #endregion Ctor
+
+        #region Services
+
+        /// <summary>
+        /// Fluent add-service with contract and implementation
+        /// </summary>
+        /// <typeparam name="TContract"></typeparam>
+        /// <typeparam name="TImplementation"></typeparam>
+        /// <param name="implementation"></param>
+        /// <returns></returns>
+        public ComponentRenderer<TComponent> AddService<TContract, TImplementation>(TImplementation implementation) where TImplementation : TContract
+
+        {
+            templater.AddService<TContract, TImplementation>(implementation);
+            return this;
+        }
+
+        /// <summary>
+        /// Fluent add-service with implemention
+        /// </summary>
+        /// <typeparam name="TImplementation"></typeparam>
+        /// <param name="implementation"></param>
+        /// <returns></returns>
+        public ComponentRenderer<TComponent> AddService<TImplementation>(TImplementation implementation)
+
+        {
+            templater.AddService<TImplementation>(implementation);
+            return this;
+        }
+
+        #endregion Services
+
+        #region Set Parameters
+
+        /// <summary>
+        /// Sets the <paramref name="value"/> to the parameter selected with the <paramref name="parameterSelector"/>.
+        /// </summary>
+        /// <typeparam name="TValue">Type of <paramref name="value"/>.</typeparam>
+        /// <param name="parameterSelector">A lambda function that selects the parameter.</param>
+        /// <param name="value">The value to pass to <typeparamref name="TComponent"/>.</param>
+        /// <returns>This <see cref="ComponentRenderer{TComponent}"/> so that additional calls can be chained.</returns>
+        public ComponentRenderer<TComponent> Set<TValue>(Expression<Func<TComponent, TValue>> parameterSelector, TValue value)
+        {
+            if (value is null)
+                throw new ArgumentNullException(nameof(value));
+
+            parameters.Add(GetParameterName(parameterSelector), value);
+            return this;
+        }
+
+        private static string GetParameterName<TValue>(Expression<Func<TComponent, TValue>> parameterSelector)
+        {
+            if (parameterSelector is null)
+                throw new ArgumentNullException(nameof(parameterSelector));
+
+            if (parameterSelector.Body is not MemberExpression memberExpression ||
+                memberExpression.Member is not PropertyInfo propInfoCandidate)
+                throw new ArgumentException($"The parameter selector '{parameterSelector}' does not resolve to a public property on the component '{typeof(TComponent)}'.", nameof(parameterSelector));
+
+            var propertyInfo = propInfoCandidate.DeclaringType != TComponentType
+                ? TComponentType.GetProperty(propInfoCandidate.Name, propInfoCandidate.PropertyType)
+                : propInfoCandidate;
+
+            var paramAttr = propertyInfo?.GetCustomAttribute<ParameterAttribute>(inherit: true);
+
+            if (propertyInfo is null || paramAttr is null)
+                throw new ArgumentException($"The parameter selector '{parameterSelector}' does not resolve to a public property on the component '{typeof(TComponent)}' with a [Parameter] or [CascadingParameter] attribute.", nameof(parameterSelector));
+
+            return propertyInfo.Name;
+        }
+
+        #endregion Set Parameters
+
+        /// <summary>
+        /// Builds the <see cref="ParameterView"/> with the parameters added to the builder.
+        /// </summary>
+        /// <returns>The created <see cref="ParameterView"/>.</returns>
+        private ParameterView Build() => ParameterView.FromDictionary(parameters);
+
+        /// <summary>
+        /// Render the component to HTML
+        /// </summary>
+        /// <returns></returns>
+        public string Render()
+        {
+            // renders the component and returns the markup HTML
+            return templater.RenderComponent<TComponent>(Build());
+        }
+    }
+}