Use MEF Metadata for Readers and Writers

Unsettling · Aug 27, 2019 · d7ac412 · d7ac412
1 parent 994b889
commit d7ac412
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Showing 9 changed files with 60 additions and 34 deletions.
diff --git a/src/FeatureFlagger.ConfigurationReaders/ConfigReader.cs b/src/FeatureFlagger.ConfigurationReaders/ConfigReader.cs
@@ -7,10  7,11 @@
     using System.Linq;
     using FeatureFlagger.Domain;
 
-    [ExportMetadata("Name", "CONFIG")]
-    [Export(typeof(IConfigurationReader))]
     [Export(typeof(IConfigurationReader)),
         ExportMetadata(Constants.Reader, Constants.Config)]
     public class ConfigReader : IConfigurationReader
     {
         // NOTE: this method is the same for StoreReader.
         public Feature Read(string featureName, IEnumerable<Feature> features)
         {
             return

diff --git a/src/FeatureFlagger.ConfigurationReaders/Constants.cs b/src/FeatureFlagger.ConfigurationReaders/Constants.cs
@@ -0,0  1,9 @@
 namespace FeatureFlagger.ConfigurationReaders
 {
     public static class Constants
     {
         public const string Config = "CONFIG";
         public const string Reader = "READER";
         public const string Store  = "STORE";
     }
 }
diff --git a/src/FeatureFlagger.ConfigurationReaders/IReaderMetadata.cs b/src/FeatureFlagger.ConfigurationReaders/IReaderMetadata.cs
@@ -0,0  1,7 @@
 namespace FeatureFlagger.ConfigurationReaders
 {
     public interface IReaderMetadata
     {
         string Reader { get; }
     }
 }
diff --git a/src/FeatureFlagger.ConfigurationReaders/StoreReader.cs b/src/FeatureFlagger.ConfigurationReaders/StoreReader.cs
@@ -9,9  9,11 @@ namespace FeatureFlagger.ConfigurationReaders
 
     using FeatureFlagger.Domain;
 
-    [Export(typeof(IConfigurationReader))]
     [Export(typeof(IConfigurationReader)),
         ExportMetadata(Constants.Reader, Constants.Store)]
     public class StoreReader : IConfigurationReader
     {
         // NOTE: this method is the same for ConfigReader.
         public Feature Read(string featureName, IEnumerable<Feature> features)
         {
             return

diff --git a/src/FeatureFlagger.ConfigurationWriters/Constants.cs b/src/FeatureFlagger.ConfigurationWriters/Constants.cs
@@ -0,0  1,8 @@
 namespace FeatureFlagger.ConfigurationWriters
 {
     public static class Constants
     {
         public const string Writer = "WRITER";
         public const string Store  = "STORE";
     }
 }
diff --git a/src/FeatureFlagger.ConfigurationWriters/IConfigurationWriter.cs b/src/FeatureFlagger.ConfigurationWriters/IConfigurationWriter.cs
@@ -4,11  4,6 @@
 
     public interface IConfigurationWriter
     {
-        /// <summary>
-        /// The Name of the implementation.
-        /// </summary>
-        string Name { get; }
-
         void Create(Feature feature);
 
         void Update(Feature feature);

diff --git a/src/FeatureFlagger.ConfigurationWriters/IWriterMetadata.cs b/src/FeatureFlagger.ConfigurationWriters/IWriterMetadata.cs
@@ -0,0  1,7 @@
 namespace FeatureFlagger.ConfigurationReaders
 {
     public interface IWriterMetadata
     {
         string Writer { get; }
     }
 }
diff --git a/src/FeatureFlagger.ConfigurationWriters/StoreWriter.cs b/src/FeatureFlagger.ConfigurationWriters/StoreWriter.cs
@@ -7,20  7,17 @@
 
     using Feature = Domain.Feature;
 
-    [Export(typeof(IConfigurationWriter))]
     [Export(typeof(IConfigurationWriter)),
         ExportMetadata(Constants.Writer, Constants.Store)]
     public class StoreWriter : IConfigurationWriter
     {
         private readonly string connectionString;
 
         private StoreWriter()
         {
-            this.Name = "STORE";
-
             this.connectionString = ConfigurationManager.ConnectionStrings["FeatureFlagger_DB"].ConnectionString;
         }
 
-        public string Name { get; }
-
         public void Create(Feature feature)
         {
             this.CreateFeature(feature);

diff --git a/src/FeatureFlagger/FeatureFlagger.cs b/src/FeatureFlagger/FeatureFlagger.cs
@@ -30,11  30,11 @@ private FeatureFlagger()
         [ImportMany]
         public static IEnumerable<IBehaviour> Behaviours { get; private set; }
 
-        [ImportMany(typeof(IConfigurationReader))]
-        private static IEnumerable<IConfigurationReader> Readers { get; set; }
         [ImportMany]
         private static IEnumerable<Lazy<IConfigurationReader, IReaderMetadata>> Readers { get; set; }
 
         [ImportMany]
-        private static IEnumerable<IConfigurationWriter> Writers { get; set; }
         private static IEnumerable<Lazy<IConfigurationWriter, IWriterMetadata>> Writers { get; set; }
 
         public static IEnumerable<Feature> Features { get; private set; }
 
@@ -47,34  47,36 @@ public static void SetFeatures()
             Features = Reader.ReadAll();
         }
 
-        private static void SetReader()
         private static IConfigurationReader SetReader()
         {
             // set the configuation reader based on an AppSetting.
             var source =
                 ConfigurationManager.AppSettings["FeatureFlaggerSource"]
                 ?? Constants.Config;
-            Reader =
-                Readers.ToList()
-                    .Find(
-                        f =>
-                        f.Name.Equals(
-                            source,
-                            StringComparison.OrdinalIgnoreCase));
 
             return Readers.ToList()
                 .Find(
                     f =>
                     f.Metadata.Reader.Equals(
                         source,
                         StringComparison.OrdinalIgnoreCase))
                     .Value;
         }
 
-        private static void SetWriter()
         private static IConfigurationWriter SetWriter()
         {
             // set the configuation writer based on an AppSetting.
             var source =
                 ConfigurationManager.AppSettings["FeatureFlaggerSource"]
                 ?? Constants.Config;
-            Writer =
-                Writers.ToList()
-                    .Find(
-                        f =>
-                        f.Name.Equals(
-                            source,
-                            StringComparison.OrdinalIgnoreCase));
 
             return Writers.ToList()
                 .Find(
                     f =>
                     f.Metadata.Writer.Equals(
                         source,
                         StringComparison.OrdinalIgnoreCase))
                     .Value;
         }
 
         private void SetImports()
@@ -88,8  90,6 @@ private void SetImports()
             var container = configuration.CreateContainer();
             container.SatisfyImports(this);
             Behaviours = container.GetExports<IBehaviour>();
-            Readers = container.GetExports<IConfigurationReader>();
-            Writers = container.GetExports<IConfigurationWriter>();
         }
     }
 }