Use MEF v.1

Uses MEF v.1 and adds User Behaviour.
Unsettling · Dec 13, 2018 · 44dfac3 · 44dfac3
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diff --git a/EnabledBehaviour.cs b/EnabledBehaviour.cs
@@ -0,0  1,15 @@
 namespace RoyalLondon.IntermediaryManagement.Api.FeatureFlagger.Behaviours
 {
     using System;
     using System.Collections.Generic;
     using System.ComponentModel.Composition;
 
     [Export(typeof(IBehaviour))]
     public class EnabledBehaviour : IBehaviour
     {
         public Func<Dictionary<string, string>, bool> Behaviour()
         {
             return x => Convert.ToBoolean(x["enabled"]);
         }
     }
 }
diff --git a/ExampleFeatureFlagger.cs b/ExampleFeatureFlagger.cs
@@ -0,0  1,10 @@
 namespace RoyalLondon.IntermediaryManagement.Api.FeatureFlagger.Features
 {
     /*
      * SSO (Single Sign On) will gradually become available so
      * this flag is to manage the roll-out.
      */
     public class ExampleFeatureFlagger : IFeatureFlagger
     {
     }
 }
diff --git a/Feature.cs b/Feature.cs
@@ -0,0  1,31 @@
 namespace RoyalLondon.IntermediaryManagement.Api.FeatureFlagger
 {
     using System.Collections.Generic;
 
     public class Feature
     {
         public Feature(string name)
         {
             this.Flags = new List<Flag>();
             this.Name = name;
         }
 
         [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Design", "CA1002:DoNotExposeGenericLists", Justification = "Not inherited")]
         public Feature(string name, List<Flag> flags)
         {
             this.Flags = flags;
             this.Name = name;
         }
 
         public string Name { get; private set; }
 
         [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Design", "CA1002:DoNotExposeGenericLists", Justification = "Not inherited")]
         public List<Flag> Flags { get; }
 
         public Feature Add(Flag flag)
         {
             this.Flags.Add(flag);
             return this;
         }
     }
 }
diff --git a/FeatureFlagger.cs b/FeatureFlagger.cs
@@ -0,0  1,63 @@
 namespace RoyalLondon.IntermediaryManagement.Api.FeatureFlagger
 {
     using System.Collections.Generic;
     using System.ComponentModel.Composition;
     using System.ComponentModel.Composition.Hosting;
     using System.Configuration;
     using System.Reflection;
 
     using RoyalLondon.IntermediaryManagement.Api.FeatureFlagger.Behaviours;
 
     [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Naming", "CA1724:TypeNamesShouldNotMatchNamespaces", Justification = "Naming is hard")]
     public sealed class FeatureFlagger
     {
         static FeatureFlagger()
         {
             // ReSharper disable once ObjectCreationAsStatement
             new FeatureFlagger();
         }
 
         private FeatureFlagger()
         {
             SetBehaviours();
             SetFeatures();
         }
 
         [ImportMany]
         public static IEnumerable<IBehaviour> Behaviours { get; private set; }
 
         public static IEnumerable<Feature> Features { get; private set; }
 
         private static void SetFeatures()
         {
             Features =
                 (List<Feature>)ConfigurationManager.GetSection("features");
         }
 
         private void SetBehaviours()
         {
             // wouldn't it be nice if Microsoft.Composition was available?
             var catalog = new AggregateCatalog();
             try
             {
                 catalog.Catalogs.Add(
                     new AssemblyCatalog(
                         typeof(IBehaviour).GetTypeInfo().Assembly));
                 var container = new CompositionContainer(catalog);
                 try
                 {
                     container.SatisfyImportsOnce(this);
                     Behaviours = container.GetExportedValues<IBehaviour>();
                 }
                 finally
                 {
                     container.Dispose();
                 }
             }
             finally
             {
                 catalog.Dispose();
             }
         }
     }
 }
diff --git a/FeatureFlaggerExtensions.cs b/FeatureFlaggerExtensions.cs
@@ -0,0  1,45 @@
 namespace RoyalLondon.IntermediaryManagement.Api.FeatureFlagger
 {
     using System;
     using System.Collections.Generic;
     using System.Linq;
 
     public static class FeatureFlaggerExtensions
     {
         public static bool IsEnabled(this IFeatureFlagger featureFlagger)
         {
             var behaviours = FeatureFlagger.Behaviours.ToList();
             var flags = GetFlags(featureFlagger);
 
             return !(from flag in flags
                      let behaviour =
                          behaviours.FirstOrDefault(
                              b =>
                              b.GetType()
                                  .Name.ToUpperInvariant()
                                  .Contains(flag.Name.ToUpperInvariant()))
                      let func = behaviour.Behaviour()
                      where func(flag.Properties) == false
                      select flag).Any();
         }
 
         private static IEnumerable<Flag> GetFlags(IFeatureFlagger featureFlagger)
         {
             var featureName =
                 featureFlagger.GetType().Name
                 .Replace("FeatureFlagger", string.Empty);
             var feature =
                 FeatureFlagger.Features.ToList()
                     .Find(
                         f =>
                         f.Name.Equals(
                             featureName,
                             StringComparison.OrdinalIgnoreCase));
 
             // always add the feature name to each flag as a property.
             feature.Flags.ForEach(f => f.Add("feature", feature.Name));
 
             return feature.Flags;
         }
     }
 }
diff --git a/FeaturesSection.cs b/FeaturesSection.cs
@@ -0,0  1,75 @@
 namespace RoyalLondon.IntermediaryManagement.Api.FeatureFlagger
 {
     using System;
     using System.Collections.Generic;
     using System.Configuration;
     using System.Globalization;
     using System.Linq;
     using System.Xml;
 
     public class FeaturesSection : IConfigurationSectionHandler
     {
         [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Design", "CA1059:MembersShouldNotExposeCertainConcreteTypes", MessageId = "System.Xml.XmlNode", Justification = "Standard method")]
         public object Create(
             object parent,
             object configContext,
             XmlNode section)
         {
             var features = new List<Feature>();
 
             foreach (XmlNode childNode in section.ChildNodes)
             {
                 var flag = EnabledFlag(childNode.Attributes);
                 var feature =
                     new Feature(
                         childNode.Attributes?.GetNamedItem("name").InnerText);
                 feature.Flags.Add(flag);
 
                 foreach (XmlNode node in childNode.ChildNodes)
                 {
                     if (node.Attributes == null)
                     {
                         continue;
                     }
 
                     var attrs =
                         node.Attributes.Cast<XmlAttribute>()
                             .ToDictionary(
                                 attr => attr.Name,
                                 attr => attr.InnerText);
 
                     // title case is required when looking up Behaviours.
                     var info = new CultureInfo("en-US").TextInfo;
                     var name = info.ToLower(node.Name);
 
                     feature.Flags.Add(new Flag(name, attrs));
                 }
 
                 features.Add(feature);
             }
 
             return features;
         }
 
         private static Flag EnabledFlag(XmlAttributeCollection attributes)
         {
             string enabled = null;
             if (attributes != null)
             {
                 enabled = attributes.GetNamedItem("enabled").InnerText;
             }
 
             if (string.IsNullOrWhiteSpace(enabled))
             {
                 throw new ArgumentException("enabled attribute is required");
             }
 
             var flag =
                 new Flag(
                     "Enabled",
                     new Dictionary<string, string> { { "enabled", enabled } });
 
             return flag;
         }
     }
 }
diff --git a/Flag.cs b/Flag.cs
@@ -0,0  1,29 @@
 namespace RoyalLondon.IntermediaryManagement.Api.FeatureFlagger
 {
     using System.Collections.Generic;
 
     public class Flag
     {
         public Flag(string name)
         {
             this.Properties = new Dictionary<string, string>();
             this.Name = name;
         }
 
         public Flag(string name, Dictionary<string, string> properties)
         {
             this.Properties = properties;
             this.Name = name;
         }
 
         public string Name { get; private set; }
 
         public Dictionary<string, string> Properties { get; }
 
         public Flag Add(string key, string value)
         {
             this.Properties.Add(key, value);
             return this;
         }
     }
 }
diff --git a/FromBehaviour.cs b/FromBehaviour.cs
@@ -0,0  1,15 @@
 namespace RoyalLondon.IntermediaryManagement.Api.FeatureFlagger.Behaviours
 {
     using System;
     using System.Collections.Generic;
     using System.ComponentModel.Composition;
 
     [Export(typeof(IBehaviour))]
     public class FromBehaviour : IBehaviour
     {
         public Func<Dictionary<string, string>, bool> Behaviour()
         {
             return x => DateTime.UtcNow.Date >= DateTime.Parse(x["date"]).Date;
         }
     }
 }
diff --git a/IBehaviour.cs b/IBehaviour.cs
@@ -0,0  1,10 @@
 namespace RoyalLondon.IntermediaryManagement.Api.FeatureFlagger.Behaviours
 {
     using System;
     using System.Collections.Generic;
 
     public interface IBehaviour
     {
         Func<Dictionary<string, string>, bool> Behaviour();
     }
 }
diff --git a/IFeatureFlagger.cs b/IFeatureFlagger.cs
@@ -0,0  1,6 @@
 namespace RoyalLondon.IntermediaryManagement.Api.FeatureFlagger
 {
     public interface IFeatureFlagger
     {
     }
 }
diff --git a/IUser.cs b/IUser.cs
@@ -0,0  1,9 @@
 namespace RoyalLondon.IntermediaryManagement.Api.FeatureFlagger.Behaviours
 {
     public interface IUser
     {
         string UserName();
 
         bool UserHasFeature(string userName, string featureName);
     }
 }
diff --git a/README.md b/README.md
@@ -1,4  1,4 @@
-# FeatureFlagger
 # FeatureFlagger
 ![Image of Flag](https://github.com/Boggin/FeatureFlagger/raw/master/assets/flag-64x64.png) Yet Another Feature Flag (Feature Toggle / Feature Switch) implementation.
 
 [![Build status](https://ci.appveyor.com/api/projects/status/f3ov0d8fqfy46yuu/branch/master?svg=true)](https://ci.appveyor.com/project/Boggin/featureflagger/branch/master)

diff --git a/User.cs b/User.cs
@@ -0,0  1,45 @@
 namespace RoyalLondon.IntermediaryManagement.Api.FeatureFlagger.Behaviours
 {
     using System;
     using System.ComponentModel.Composition;
     using System.Linq;
 
     using RoyalLondon.IntermediaryManagement.Api.Entities;
 
     [Export(typeof(IUser))]
     public class User : IUser
     {
         public bool UserHasFeature(string userName, string featureName)
         {
             IntermediaryManagement_DB context = null;
             try
             {
                 context = IntermediariesContainerFactory.Create();
                 var user =
                     context.Users.FirstOrDefault(
                         u =>
                         u.Name.Equals(
                             userName,
                             StringComparison.OrdinalIgnoreCase));
                 var hasFeature =
                     user?.Features.Any(
                         f =>
                         f.Name.Equals(
                             featureName,
                             StringComparison.OrdinalIgnoreCase));
 
                 return hasFeature == true;
             }
             finally
             {
                 context?.Dispose();
             }
         }
 
         public string UserName()
         {
             // TODO: get the authorised user from SSO.
             return "dummy";
         }
     }
 }