feat: introduce FlagdProvider constructor accepting FlagdConfig as parameter (#57)

Signed-off-by: odubajDT <[email protected]>

Author: odubajDT

Diff for: src/OpenFeature.Contrib.Providers.Flagd/FlagdConfig.cs

@@ -3,7 +3,10 @@
 namespace OpenFeature.Contrib.Providers.Flagd
 
 {
-    internal class FlagdConfig
+    /// <summary>
+    ///     FlagdConfig is the configuration object for flagD.
+    /// </summary>
+    public class FlagdConfig
     {
         internal const string EnvVarHost = "FLAGD_HOST";
         internal const string EnvVarPort = "FLAGD_PORT";

Diff for: src/OpenFeature.Contrib.Providers.Flagd/FlagdProvider.cs

@@ -84,6 +84,33 @@ public FlagdProvider(Uri url)
             _client = BuildClientForPlatform(url);
         }
 
+        /// <summary>
+        ///     Constructor of the provider.
+        ///     <param name="config">The FlagdConfig object</param>
+        ///     <exception cref="ArgumentNullException">if no config object is provided.</exception>
+        /// </summary>
+        public FlagdProvider(FlagdConfig config)
+        {
+            if (config == null)
+            {
+                throw new ArgumentNullException(nameof(config));
+            }
+
+            _config = config;
+
+            _client = BuildClientForPlatform(_config.GetUri());
+
+            _mtx = new System.Threading.Mutex();
+
+            if (_config.CacheEnabled)
+            {
+                _cache = new LRUCache<string, object>(_config.MaxCacheSize);
+                Task.Run(async () =>
+                {
+                    await HandleEvents();
+                });
+            }
+        }
 
         // just for testing, internal but visible in tests
         internal FlagdProvider(Service.ServiceClient client, FlagdConfig config, ICache<string, object> cache = null)
@@ -102,6 +129,9 @@ internal FlagdProvider(Service.ServiceClient client, FlagdConfig config, ICache<
             }
         }
 
+        // just for testing, internal but visible in tests
+        internal FlagdConfig GetConfig() => _config;
+
         /// <summary>
         /// Get the provider name.
         /// </summary>

Diff for: test/OpenFeature.Contrib.Providers.Flagd.Test/FlagdProviderTest.cs

@@ -78,6 +78,45 @@ public void TestGetProviderWithDefaultConfig()
             Assert.NotNull(client);
         }
 
+        [Fact]
+        public void TestGetProviderWithConfig()
+        {
+            // Create a config with default values set
+            var config = new FlagdConfig();
+
+            // Set env variables (should be ignored by the constructor)
+            System.Environment.SetEnvironmentVariable(FlagdConfig.EnvCertPart, "path");
+            System.Environment.SetEnvironmentVariable(FlagdConfig.EnvVarHost, "localhost111");
+            System.Environment.SetEnvironmentVariable(FlagdConfig.EnvVarPort, "5001");
+            System.Environment.SetEnvironmentVariable(FlagdConfig.EnvVarTLS, "true");
+            System.Environment.SetEnvironmentVariable(FlagdConfig.EnvVarCache, "LRU");
+            System.Environment.SetEnvironmentVariable(FlagdConfig.EnvVarMaxCacheSize, "20");
+
+            // Create provider, which ignores the env vars and uses the config
+            var flagdProvider = new FlagdProvider(config);
+
+            // Client should no be nil
+            var client = flagdProvider.GetClient();
+            Assert.NotNull(client);
+
+            // Retrieve config for assertions
+            config = flagdProvider.GetConfig();
+
+            // Assert
+            Assert.Equal("", config.CertificatePath);
+            Assert.Equal(new Uri("http://localhost:8013"), config.GetUri());
+            Assert.False(config.CacheEnabled);
+            Assert.Equal(0, config.MaxCacheSize);
+
+            // Cleanup
+            System.Environment.SetEnvironmentVariable(FlagdConfig.EnvCertPart, "");
+            System.Environment.SetEnvironmentVariable(FlagdConfig.EnvVarHost, "");
+            System.Environment.SetEnvironmentVariable(FlagdConfig.EnvVarPort, "");
+            System.Environment.SetEnvironmentVariable(FlagdConfig.EnvVarTLS, "");
+            System.Environment.SetEnvironmentVariable(FlagdConfig.EnvVarCache, "");
+            System.Environment.SetEnvironmentVariable(FlagdConfig.EnvVarMaxCacheSize, "");
+        }
+
         [Fact]
         public void TestResolveBooleanValue()
         {