Fixing issues with ScriptSettingsManager reset when the configuration…

… factory returned a cached configuration instance
RajeshManam · Mar 29, 2018 · e5b569e · e5b569e
1 parent 043561c
commit e5b569e
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Showing 2 changed files with 39 additions and 1 deletion.
diff --git a/src/WebJobs.Script/Config/ScriptSettingsManager.cs b/src/WebJobs.Script/Config/ScriptSettingsManager.cs
@@ -129,7 +129,8 @@ private void UpdateSettingInCache(string settingKey, string settingValue)
 
         public virtual void Reset()
         {
-            _configuration = new Lazy<IConfiguration>(_configurationFactory);
+            Lazy<IConfiguration> current = _configuration;
+            _configuration = new Lazy<IConfiguration>(() => InitializeConfiguration(current));
 
             _settingsCache.Clear();
         }
@@ -153,6 +154,24 @@ public virtual void SetSetting(string settingKey, string settingValue)
             }
         }
 
+        private IConfiguration InitializeConfiguration(Lazy<IConfiguration> currentConfiguration)
+        {
+            var configuration = _configurationFactory();
+
+            // If the factory returned a cached instance
+            // that is the same as the instance we previously had,
+            // reload the configuration on that instance.
+            if (configuration is IConfigurationRoot root &&
+                currentConfiguration != null &&
+                currentConfiguration.IsValueCreated &&
+                object.ReferenceEquals(currentConfiguration.Value, root))
+            {
+                root.Reload();
+            }
+
+            return configuration;
+        }
+
         private static IConfigurationRoot BuildConfiguration()
         {
             var configurationBuilder = new ConfigurationBuilder()

diff --git a/test/WebJobs.Script.Tests/ScriptSettingsManagerTests.cs b/test/WebJobs.Script.Tests/ScriptSettingsManagerTests.cs
@@ -7,6 +7,7 @@
 using System.Text;
 using System.Threading.Tasks;
 using Microsoft.Azure.WebJobs.Script.Config;
+using Microsoft.Extensions.Configuration;
 using Xunit;
 
 namespace Microsoft.Azure.WebJobs.Script.Tests
@@ -37,5 +38,23 @@ public void UniqueSlotName_ReturnsExpectedValue(string siteName, string slotName
                 Assert.Equal(expectedValue, ScriptSettingsManager.Instance.AzureWebsiteUniqueSlotName);
             }
         }
+
+        [Fact]
+        public void Reset_ReloadsEnvironmentChanges()
+        {
+            using (var variable = new TestScopedEnvironmentVariable(nameof(Reset_ReloadsEnvironmentChanges), "foo"))
+            {
+                var configuration = new ConfigurationBuilder()
+                    .AddEnvironmentVariables()
+                    .Build();
+
+                ScriptSettingsManager.Instance.SetConfigurationFactory(() => configuration);
+                Assert.Equal("foo", ScriptSettingsManager.Instance.GetSetting(nameof(Reset_ReloadsEnvironmentChanges)));
+
+                Environment.SetEnvironmentVariable(nameof(Reset_ReloadsEnvironmentChanges), "bar");
+                ScriptSettingsManager.Instance.Reset();
+                Assert.Equal("bar", ScriptSettingsManager.Instance.GetSetting(nameof(Reset_ReloadsEnvironmentChanges)));
+            }
+        }
     }
 }