ConfigurationParser used in ParsableRetrievalStrategy now uses factory method and lives transiently during Parse call only

Author: TimurRybakov

src/ConfigurationRepository.Dapper/DependencyInjection/ConfigurationBuilderExtensions.cs

@@ -27,8 +27,6 @@ public static IConfigurationBuilder AddDapperRepository(
         configureRepository.Invoke(repository);
         configureSource?.Invoke(source);
 
-        source.RetrievalStrategy ??= DictionaryRetrievalStrategy.Instance;
-
         return builder.Add(source);
     }
 
@@ -52,8 +50,6 @@ public static IConfigurationBuilder AddDapperJsonRepository(
         configureRepository.Invoke(repository);
         configureSource?.Invoke(source);
 
-        source.ConfigurationParser ??= new JsonConfigurationParser();
-
         return builder.Add(source);
     }
 }

src/ConfigurationRepository.Dapper/README.md

@@ -16,6 +16,8 @@ Let's assume that we have a database that stores a configuration table as key-va
 
 So then in our application Program.cs file we may add a configuration provider like this:
 > ```csharp
+> using ConfigurationRepository;
+>
 > var builder = WebApplication.CreateBuilder(args);
 > 
 > var connectionString = builder.Configuration.GetConnectionString("Dapper");
@@ -37,6 +39,8 @@ So then in our application Program.cs file we may add a configuration provider l
 
 If our database source can change at any time in any way we may also add configuration reloader that with periodically reload our configuration from database:
 > ```csharp
+> using ConfigurationRepository;
+>
 > var builder = WebApplication.CreateBuilder(args);
 > 
 > var connectionString = builder.Configuration.GetConnectionString("Dapper");
@@ -78,6 +82,8 @@ What if our config in database is too heavy to reload it frequently and we want
 
 Then we make our configuration versioned by adding SelectCurrentVersionQuery to our repository:
 > ```csharp
+> using ConfigurationRepository;
+> 
 > var builder = WebApplication.CreateBuilder(args);
 > 
 > var connectionString = builder.Configuration.GetConnectionString("Dapper");

src/ConfigurationRepository.EntityFramework/DependencyInjection/ConfigurationBuilderExtensions.cs

@@ -46,7 +46,6 @@ public static IConfigurationBuilder AddEfCoreRepository(
                 new RepositoryDbContext(options));
 
         source.Repository = repository;
-        source.RetrievalStrategy = DictionaryRetrievalStrategy.Instance;
 
         configureSource?.Invoke(source);
 
@@ -98,8 +97,6 @@ public static IConfigurationBuilder AddEfCoreJsonRepository(
             };
 
         source.Repository = repository;
-        source.ConfigurationParser = new JsonConfigurationParser();
-
         configureSource?.Invoke(source);
 
         return builder.Add(source);

src/ConfigurationRepository.SqlClient/DependencyInjection/ConfigurationBuilderExtensions.cs

@@ -21,14 +21,13 @@ public static IConfigurationBuilder AddSqlClientRepository(
     {
         var source = new ConfigurationRepositorySource();
         var repository = new SqlClientDictionaryConfigurationRepository();
+        repository.TryAddConnectionString(builder);
 
         source.Repository = repository;
 
         configureRepository.Invoke(repository);
         configureSource?.Invoke(source);
 
-        source.RetrievalStrategy ??= DictionaryRetrievalStrategy.Instance;
-
         return builder.Add(source);
     }
 
@@ -46,14 +45,26 @@ public static IConfigurationBuilder AddSqlClientJsonRepository(
     {
         var source = new ParsableConfigurationRepositorySource();
         var repository = new SqlClientParsableConfigurationRepository();
+        repository.TryAddConnectionString(builder);
 
         source.Repository = repository;
 
         configureRepository.Invoke(repository);
         configureSource?.Invoke(source);
 
-        source.ConfigurationParser ??= new JsonConfigurationParser();
-
         return builder.Add(source);
     }
+
+    private static SqlClientConfigurationRepository TryAddConnectionString(
+        this SqlClientConfigurationRepository repository,
+        IConfigurationBuilder builder)
+    {
+        var connectionString = builder.GetDatabaseConnectionString();
+        if (connectionString is not null)
+        {
+            repository.ConnectionString = connectionString;
+        }
+
+        return repository;
+    }
 }

src/ConfigurationRepository/DependencyInjection/ConfigurationBuilderExtensions.cs

@@ -13,7 +13,7 @@ public static class ConfigurationBuilderExtensions
     /// <param name="builder">A configuration builder instance for adding <see cref="IRepository"/> or it`s descendant.</param>
     /// <param name="repository">An <see cref="IRepository"/> object.</param>
     /// <param name="configureSource">If set, configures <see cref="ConfigurationRepositorySource"/>.</param>
-    /// <returns>The <see cref="IConfigurationBuilder"/>.</returns>
+    /// <returns>An <see cref="IConfigurationBuilder"/>.</returns>
     public static IConfigurationBuilder AddRepository<TSource>(
         this IConfigurationBuilder builder,
         IRepository repository,
@@ -30,13 +30,67 @@ public static IConfigurationBuilder AddRepository<TSource>(
         return builder;
     }
 
+    /// <summary>
+    /// Adds an <see cref="IRepository"/> object to <paramref name="builder"/> with <see cref="DictionaryRetrievalStrategy"/>.
+    /// </summary>
+    /// <param name="builder">A configuration builder instance for adding <see cref="IRepository"/> or it`s descendant.</param>
+    /// <param name="repository">An <see cref="IRepository"/> object.</param>
+    /// <param name="configureSource">If set, configures <see cref="ConfigurationRepositorySource"/>.</param>
+    /// <returns>An <see cref="IConfigurationBuilder"/>.</returns>
+    public static IConfigurationBuilder AddDictionaryRepository<TSource>(
+        this IConfigurationBuilder builder,
+        IRepository repository,
+        Action<TSource>? configureSource = null)
+        where TSource : ConfigurationRepositorySource, new()
+    {
+        var source = new TSource
+        {
+            Repository = repository,
+            RetrievalStrategy = DictionaryRetrievalStrategy.Instance
+        };
+        configureSource?.Invoke(source);
+
+        builder.Add(source);
+        return builder;
+    }
+
+    /// <summary>
+    /// Adds an <see cref="IRepository"/> object to <paramref name="builder"/> with <see cref="ParsableRetrievalStrategy"/>.
+    /// </summary>
+    /// <param name="builder">A configuration builder instance for adding <see cref="IRepository"/> or it`s descendant.</param>
+    /// <param name="repository">An <see cref="IRepository"/> object.</param>
+    /// <param name="parserFactory">A factory method that returns an instance of
+    /// configuration parser to be used for parsing data being loaded from repository. If not specified then a factory
+    /// creating instance of <see cref="JsonConfigurationParser"/> is used by default.</param>
+    /// <param name="configureSource">If set, configures <see cref="ConfigurationRepositorySource"/>.</param>
+    /// <returns>An <see cref="IConfigurationBuilder"/>.</returns>
+    public static IConfigurationBuilder AddParsableRepository<TSource>(
+        this IConfigurationBuilder builder,
+        IRepository repository,
+        Func<IConfigurationParser>? parserFactory = null,
+        Action<TSource>? configureSource = null)
+        where TSource : ConfigurationRepositorySource, new()
+    {
+        parserFactory ??= () => new JsonConfigurationParser();
+
+        var source = new TSource
+        {
+            Repository = repository,
+            RetrievalStrategy = new ParsableRetrievalStrategy(parserFactory)
+        };
+        configureSource?.Invoke(source);
+
+        builder.Add(source);
+        return builder;
+    }
+
     /// <summary>
     /// Adds an <see cref="IRepository"/> object to <paramref name="builder"/>.
     /// </summary>
     /// <param name="builder">A configuration builder instance for adding <see cref="IRepository"/>.</param>
     /// <param name="repository">An <see cref="IRepository"/> object.</param>
     /// <param name="configureSource">If set, configures <see cref="ConfigurationRepositorySource"/>.</param>
-    /// <returns>The <see cref="IConfigurationBuilder"/>.</returns>
+    /// <returns>An <see cref="IConfigurationBuilder"/>.</returns>
     public static IConfigurationBuilder AddRepository(
         this IConfigurationBuilder builder,
         IRepository repository,
@@ -45,12 +99,46 @@ public static IConfigurationBuilder AddRepository(
         return builder.AddRepository<ConfigurationRepositorySource>(repository, configureSource);
     }
 
+    /// <summary>
+    /// Adds an <see cref="IRepository"/> object to <paramref name="builder"/> with <see cref="DictionaryRetrievalStrategy"/>.
+    /// </summary>
+    /// <param name="builder">A configuration builder instance for adding <see cref="IRepository"/>.</param>
+    /// <param name="repository">An <see cref="IRepository"/> object.</param>
+    /// <param name="configureSource">If set, configures <see cref="ConfigurationRepositorySource"/>.</param>
+    /// <returns>An <see cref="IConfigurationBuilder"/>.</returns>
+    public static IConfigurationBuilder AddDictionaryRepository(
+        this IConfigurationBuilder builder,
+        IRepository repository,
+        Action<ConfigurationRepositorySource>? configureSource = null)
+    {
+        return builder.AddDictionaryRepository<ConfigurationRepositorySource>(repository, configureSource);
+    }
+
+    /// <summary>
+    /// Adds an <see cref="IRepository"/> object to <paramref name="builder"/> with <see cref="DictionaryRetrievalStrategy"/>.
+    /// </summary>
+    /// <param name="builder">A configuration builder instance for adding <see cref="IRepository"/>.</param>
+    /// <param name="repository">An <see cref="IRepository"/> object.</param>
+    /// <param name="parserFactory">A factory method that returns an instance of
+    /// configuration parser to be used for parsing data being loaded from repository. If not specified then a factory
+    /// creating instance of <see cref="JsonConfigurationParser"/> is used by default.</param>
+    /// <param name="configureSource">If set, configures <see cref="ConfigurationRepositorySource"/>.</param>
+    /// <returns>An <see cref="IConfigurationBuilder"/>.</returns>
+    public static IConfigurationBuilder AddParsableRepository(
+        this IConfigurationBuilder builder,
+        IRepository repository,
+        Func<IConfigurationParser>? parserFactory = null,
+        Action<ConfigurationRepositorySource>? configureSource = null)
+    {
+        return builder.AddParsableRepository<ConfigurationRepositorySource>(repository, parserFactory, configureSource);
+    }
+
     /// <summary>
     /// Sets a default action to be invoked for repository providers when an error occurs.
     /// </summary>
     /// <param name="builder">A configuration builder instance for adding property with handler.</param>
-    /// <param name="handler">The Action to be invoked on a database load exception.</param>
-    /// <returns>The <see cref="IConfigurationBuilder"/>.</returns>
+    /// <param name="handler">An Action to be invoked on a database load exception.</param>
+    /// <returns>An <see cref="IConfigurationBuilder"/>.</returns>
     public static IConfigurationBuilder SetRepositoryLoadExceptionHandler(this IConfigurationBuilder builder,
         Action<RepositoryLoadExceptionContext> handler)
     {
@@ -63,8 +151,8 @@ public static IConfigurationBuilder SetRepositoryLoadExceptionHandler(this IConf
     /// <summary>
     /// Gets a default action to be invoked for repository providers when an error occurs.
     /// </summary>
-    /// <param name="builder">The <see cref="IConfigurationBuilder"/>.</param>
-    /// <returns>The Action to be invoked on a database load exception, if set.</returns>
+    /// <param name="builder">An <see cref="IConfigurationBuilder"/>.</param>
+    /// <returns>An <see cref="Action{RepositoryLoadExceptionContext}"/> to be invoked on a database load exception, if set.</returns>
     public static Action<RepositoryLoadExceptionContext>? GetRepositoryLoadExceptionHandler(this IConfigurationBuilder builder)
     {
         _ = builder ?? throw new ArgumentNullException(nameof(builder));
@@ -75,40 +163,45 @@ public static IConfigurationBuilder SetRepositoryLoadExceptionHandler(this IConf
     }
 
     /// <summary>
-    /// Sets a configuration parser to be used parsing data being loaded from repository.
+    /// Sets a <see cref="IConfigurationParser"/> factory that returns an instance
+    /// of configuration parser to be used for parsing data being loaded from repository.
     /// </summary>
-    /// <param name="builder">The <see cref="IConfigurationBuilder"/> to add to.</param>
-    /// <param name="parser">The configuration parser to be used parsing load data from repository.</param>
-    /// <returns>The <see cref="IConfigurationBuilder"/>.</returns>
-    public static IConfigurationBuilder SetParsableConfigurationParser(this IConfigurationBuilder builder,
-        IConfigurationParser parser)
+    /// <param name="builder">An <see cref="IConfigurationBuilder"/> to add to.</param>
+    /// <param name="parserFactory">A factory method that returns an instance of
+    /// configuration parser to be used for parsing data being loaded from repository.</param>
+    /// <returns>An <see cref="IConfigurationBuilder"/>.</returns>
+    public static IConfigurationBuilder SetConfigurationParserFactory(this IConfigurationBuilder builder,
+        Func<IConfigurationParser> parserFactory)
     {
         _ = builder ?? throw new ArgumentNullException(nameof(builder));
 
-        builder.Properties[ParsableConfigurationParserKey] = parser;
+        builder.Properties[ConfigurationParserFactoryKey] = parserFactory;
         return builder;
     }
 
     /// <summary>
-    /// Gets a configuration parser to be used when parsing configuration data being loaded from database.
-    /// If no parser is set then JsonConfigurationParser is used by default.
+    /// Gets a <see cref="IConfigurationParser"/> factory from <paramref name="builder"/>
+    /// properties. That factory returns an instanceof configuration parser to be used
+    /// for parsing data being loaded from repository. If no one is found then a factory
+    /// creating instance of <see cref="JsonConfigurationParser"/> is used by default.
     /// </summary>
-    /// <param name="builder">The <see cref="IConfigurationBuilder"/>.</param>
-    /// <returns>The configuration parser to be used parsing load data from database.</returns>
-    public static IConfigurationParser GetParsableConfigurationParser(this IConfigurationBuilder builder)
+    /// <param name="builder">An <see cref="IConfigurationBuilder"/>.</param>
+    /// <returns>A factory method that returns an instance of
+    /// configuration parser to be used for parsing data being loaded from repository.</returns>
+    public static Func<IConfigurationParser>? GetConfigurationParserFactory(this IConfigurationBuilder builder)
     {
         _ = builder ?? throw new ArgumentNullException(nameof(builder));
 
-        return (builder.Properties.TryGetValue(ParsableConfigurationParserKey, out object? parser)
-            ? (IConfigurationParser)parser : null) ?? new JsonConfigurationParser();
+        return (builder.Properties.TryGetValue(ConfigurationParserFactoryKey, out object? parserFactory)
+            ? (Func<IConfigurationParser>)parserFactory : null) ?? (() => new JsonConfigurationParser());
     }
 
     /// <summary>
     /// Sets connection string that will be used to connect to the database.
     /// </summary>
-    /// <param name="builder">The <see cref="IConfigurationBuilder"/> to add to.</param>
-    /// <param name="connectionString">The connection string to connect to the database.</param>
-    /// <returns>The <see cref="IConfigurationBuilder"/>.</returns>
+    /// <param name="builder">An <see cref="IConfigurationBuilder"/> to add to.</param>
+    /// <param name="connectionString">A connection string to connect to the database.</param>
+    /// <returns>An <see cref="IConfigurationBuilder"/>.</returns>
     public static IConfigurationBuilder SetDatabaseConnectionString(this IConfigurationBuilder builder,
         string connectionString)
     {
@@ -121,8 +214,8 @@ public static IConfigurationBuilder SetDatabaseConnectionString(this IConfigurat
     /// <summary>
     /// Gets connection string that will be used to connect to the database.
     /// </summary>
-    /// <param name="builder">The <see cref="IConfigurationBuilder"/>.</param>
-    /// <returns>The connection string to connect to the database.</returns>
+    /// <param name="builder">An <see cref="IConfigurationBuilder"/>.</param>
+    /// <returns>A connection string to connect to the database.</returns>
     public static string? GetDatabaseConnectionString(this IConfigurationBuilder builder)
     {
         _ = builder ?? throw new ArgumentNullException(nameof(builder));
@@ -134,8 +227,8 @@ public static IConfigurationBuilder SetDatabaseConnectionString(this IConfigurat
     /// <summary>
     /// Gets the <see cref="IRepository"/> that will be used to store configurations.
     /// </summary>
-    /// <param name="builder">The <see cref="IConfigurationBuilder"/>.</param>
-    /// <returns>The <see cref="IRepository"/>.</returns>
+    /// <param name="builder">An <see cref="IConfigurationBuilder"/>.</param>
+    /// <returns>An <see cref="IRepository"/>.</returns>
     public static IRepository? GetConfigurationRepository(this IConfigurationBuilder builder)
     {
         _ = builder ?? throw new ArgumentNullException(nameof(builder));
@@ -144,8 +237,8 @@ public static IConfigurationBuilder SetDatabaseConnectionString(this IConfigurat
             ? (IRepository)repository : null;
     }
 
-    private const string RepositoryKey = "ConfigurationRepository:Repository";
-    private const string RepositoryLoadExceptionHandlerKey = "ConfigurationRepository:Repository:LoadExceptionHandler";
-    private const string ParsableConfigurationParserKey = "ConfigurationRepository:ParsableConfiguration:Parser";
-    private const string RepositoryDatabaseConnectionStringKey = "ConfigurationRepository:Repository:DatabaseConnectionString";
+    private const string RepositoryKey = "ConfigurationRepository:Key";
+    private const string RepositoryLoadExceptionHandlerKey = "ConfigurationRepository:LoadExceptionHandler";
+    private const string ConfigurationParserFactoryKey = "ConfigurationRepository:ParserFactory";
+    private const string RepositoryDatabaseConnectionStringKey = "ConfigurationRepository:DatabaseConnectionString";
 }

src/ConfigurationRepository/README.md

@@ -15,6 +15,40 @@ Install-Package ConfigurationRepository
 ```
 dotnet add package ConfigurationRepository
 ```
+```csharp
+using ConfigurationRepository;
+
+var builder = WebApplication.CreateBuilder(args);
+
+var configDictData = new Dictionary<string, string?>(StringComparer.OrdinalIgnoreCase)
+{ { "DICT KEY", "DICT VALUE" } };
+
+builder.Configuration.AddDictionaryRepository(new InMemoryDictionaryRepository(configDictData));
+
+var configJsonData = """{"JSON KEY":"JSON VALUE"}""";
+
+builder.Configuration.AddParsableRepository(new InMemoryJsonRepository(configJsonData));
+
+var app = builder.Build();
+
+app.Run();
+
+class InMemoryDictionaryRepository(IDictionary<string, string?> configData) : IRepository
+{
+    public TData GetConfiguration<TData>()
+    {
+        return (TData)configData;
+    }
+}
+
+class InMemoryJsonRepository(string jsonConfig) : IRepository
+{
+    public TData GetConfiguration<TData>()
+    {
+        return (TData)Convert.ChangeType(jsonConfig, typeof(TData));
+    }
+}
+```
 
 # [Dapper configuration repository](/src/ConfigurationRepository.Dapper/README.md)