console log buffer PR feedback - comments and tweaks to options usage

Author: paulbatum

src/WebJobs.Script.WebHost/Diagnostics/BufferedConsoleWriter.cs

@@ -70,6 +70,7 @@ private void WriteToConsoleBuffer(string evt)
             }
         }
 
+        // internal only for testing - should only be used from the constructor, not intended for concurrent callers.
         internal void StartProcessingBuffer()
         {
             // intentional no-op if the task is already running

src/WebJobs.Script/Config/ConsoleLoggingOptions.cs

@@ -19,7 +19,8 @@ public ConsoleLoggingOptions()
 
         public bool LoggingDisabled { get; set; }
 
-        public bool BufferEnabled { get; set; }
+        // Use BufferSize = 0 to disable the buffer
+        public bool BufferEnabled { get; internal set; }
 
         public int BufferSize { get; set; }
     }

src/WebJobs.Script/Config/ConsoleLoggingOptionsSetup.cs

@@ -20,14 +20,17 @@ public void Configure(ConsoleLoggingOptions options)
         {
             options.LoggingDisabled = _configuration.GetValue<int>(EnvironmentSettingNames.ConsoleLoggingDisabled) == 1;
 
-            int bufferSize = _configuration.GetValue<int>(EnvironmentSettingNames.ConsoleLoggingBufferSize, ConsoleLoggingOptions.DefaultBufferSize);
-            if (bufferSize < 0)
+            int? bufferSize = _configuration.GetValue<int?>(EnvironmentSettingNames.ConsoleLoggingBufferSize);
+            if (bufferSize != null)
             {
-                throw new ArgumentOutOfRangeException(nameof(EnvironmentSettingNames.ConsoleLoggingBufferSize), "Console buffer size cannot be negative");
-            }
+                if (bufferSize < 0)
+                {
+                    throw new ArgumentOutOfRangeException(nameof(EnvironmentSettingNames.ConsoleLoggingBufferSize), "Console buffer size cannot be negative");
+                }
 
-            options.BufferEnabled = bufferSize > 0;
-            options.BufferSize = bufferSize;
+                options.BufferEnabled = bufferSize > 0;
+                options.BufferSize = bufferSize.Value;
+            }
         }
     }
 }

test/WebJobs.Script.Tests/Configuration/ConsoleLoggingOptionsSetupTests.cs

@@ -88,5 +88,21 @@ public void ConsoleLoggingOptionsSetup_CanSetBufferSize()
 
             Assert.Equal(100, options.BufferSize);
         }
+
+        [Fact]
+        public void ConsoleLoggingOptionsSetup_DoesNotOverwriteCustomBufferSizeIfNotSet()
+        {
+            var settings = new Dictionary<string, string>();
+
+            IConfiguration config = new ConfigurationBuilder()
+               .AddInMemoryCollection(settings)
+               .Build();
+
+            ConsoleLoggingOptionsSetup setup = new ConsoleLoggingOptionsSetup(config);
+            ConsoleLoggingOptions options = new ConsoleLoggingOptions { BufferSize = 100 };
+            setup.Configure(options);
+
+            Assert.Equal(100, options.BufferSize);
+        }
     }
 }