Handle listener errors

Author: Matt Mason

src/WebJobs.Script/Host/ScriptHost.cs

@@ -20,6 +20,7 @@
 using Microsoft.Azure.WebJobs.Extensions.BotFramework.Bindings;
 using Microsoft.Azure.WebJobs.Host;
 using Microsoft.Azure.WebJobs.Host.Indexers;
+using Microsoft.Azure.WebJobs.Host.Listeners;
 using Microsoft.Azure.WebJobs.Script.Binding;
 using Microsoft.Azure.WebJobs.Script.Config;
 using Microsoft.Azure.WebJobs.Script.Description;
@@ -1087,19 +1088,19 @@ private void HandleHostError(Exception exception)
                 FunctionInvocationException invocationException = exception as FunctionInvocationException;
                 NotifyInvoker(invocationException.MethodName, invocationException);
             }
-            else if (exception is FunctionIndexingException)
+            else if (exception is FunctionIndexingException || exception is FunctionListenerException)
             {
-                // For all startup time indexing errors, we accumulate them per function
-                FunctionIndexingException indexingException = exception as FunctionIndexingException;
-                string formattedError = Utility.FlattenException(indexingException);
-                AddFunctionError(FunctionErrors, indexingException.MethodName, formattedError);
+                // For all startup time indexing/listener errors, we accumulate them per function
+                FunctionException functionException = exception as FunctionException;
+                string formattedError = Utility.FlattenException(functionException);
+                AddFunctionError(FunctionErrors, functionException.MethodName, formattedError);
 
                 // Also notify the invoker so the error can also be written to the function
                 // log file
-                NotifyInvoker(indexingException.MethodName, indexingException);
+                NotifyInvoker(functionException.MethodName, functionException);
 
-                // Mark the error as handled so indexing will continue
-                indexingException.Handled = true;
+                // Mark the error as handled so execution will continue with this function disabled
+                functionException.Handled = true;
             }
             else
             {

src/WebJobs.Script/azurefunctions/functions.js

@@ -107,7 +107,7 @@ function getEntryPoint(f, context) {
             f = f[context._entryPoint];
             delete context._entryPoint;
         }
-        else if (Object.keys(f).length == 1) {
+        else if (Object.keys(f).length === 1) {
             // a single named function was exported
             var name = Object.keys(f)[0];
             f = f[name];

test/WebJobs.Script.Tests.Integration/EndToEndTestFixture.cs

@@ -51,6 +51,7 @@ protected EndToEndTestFixture(string rootPath, string testId)
             // Reset the timer logs first, since one of the tests will
             // be checking them
             TestHelpers.ClearFunctionLogs("TimerTrigger");
+            TestHelpers.ClearFunctionLogs("ListenerStartupException");
             Host = ScriptHost.Create(ScriptHostEnvironmentMock.Object, config, _settingsManager);
             Host.Start();
         }

test/WebJobs.Script.Tests.Integration/ListenerFailureTests.cs

@@ -0,0 +1,65 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the MIT License. See License.txt in the project root for license information.
+
+using System.Collections.Generic;
+using System.Threading.Tasks;
+using Xunit;
+
+namespace Microsoft.Azure.WebJobs.Script.Tests
+{
+    public class ListenerFailureTests : EndToEndTestsBase<ListenerFailureTests.TestFixture>
+    {
+        public ListenerFailureTests(TestFixture fixture) : base(fixture)
+        {
+        }
+
+        [Fact]
+        public async Task ListenerError_LogsAndDoesNotStopHost()
+        {
+            IList<string> logs = null;
+
+            await TestHelpers.Await(() =>
+            {
+                logs = TestHelpers.GetFunctionLogsAsync("ListenerStartupException", false).Result;
+                return logs.Count > 0;
+            });
+
+            // assert that listener error was captured
+            Assert.Contains(logs, (log) => log.Contains("The listener for function 'Functions.ListenerStartupException' was unable to start."));
+
+            TestHelpers.ClearFunctionLogs("TimerTrigger");
+            await TestHelpers.Await(() =>
+            {
+                logs = TestHelpers.GetFunctionLogsAsync("TimerTrigger", false).Result;
+                return logs.Count > 0;
+            });
+
+            // assert that timer function is still running
+            Assert.Contains(logs, (log) => log.Contains("Timer function ran!"));
+
+            // assert that Stop does not throw error
+            Fixture.Host.Stop();
+        }
+
+        public class TestFixture : EndToEndTestFixture
+        {
+            public TestFixture() : base(@"TestScripts\ListenerExceptions", "listeners")
+            {
+            }
+
+            public override void Dispose()
+            {
+                // host should already be stopped from test
+                try
+                {
+                    Host.Stop();
+                }
+                catch
+                {
+                }
+                Host.Dispose();
+                ServiceBusQueueClient.Close();
+            }
+        }
+    }
+}

test/WebJobs.Script.Tests.Integration/TestScripts/ListenerExceptions/ListenerStartupException/function.json

@@ -0,0 +1,11 @@
+{
+    "bindings": [
+        {
+            "type": "serviceBusTrigger",
+            "name": "inMessage",
+            "direction": "in",
+            "queueName": "samples-input-nonexistent",
+            "accessRights": "listen"
+        }
+    ]
+}

test/WebJobs.Script.Tests.Integration/TestScripts/ListenerExceptions/ListenerStartupException/index.js

@@ -0,0 +1,5 @@
+var util = require('util');
+
+module.exports = function (context, inMessage) {
+    // we don't expect this to execute, as the queue cannot be created with listen rights
+}

test/WebJobs.Script.Tests.Integration/TestScripts/ListenerExceptions/TimerTrigger/function.json

@@ -0,0 +1,11 @@
+{
+    "bindings": [
+        {
+            "type": "timerTrigger",
+            "name": "timerInfo",
+            "direction": "in",
+            "runOnStartup": true,
+            "schedule": "*/2 * * * * *"
+        }
+    ]
+}

test/WebJobs.Script.Tests.Integration/TestScripts/ListenerExceptions/TimerTrigger/index.js

@@ -0,0 +1,5 @@
+module.exports = function (context, timerInfo) {
+    var timeStamp = new Date().toISOString();
+    context.log('Timer function ran! ', timeStamp);
+    context.done();
+}

test/WebJobs.Script.Tests.Integration/TestScripts/ListenerExceptions/host.json

@@ -0,0 +1,3 @@
+{
+    "id": "function-listener-failues"
+}

test/WebJobs.Script.Tests.Integration/WebJobs.Script.Tests.Integration.csproj

@@ -443,12 +443,19 @@
     <Compile Include="Host\ScriptHostManagerTests.cs" />
     <Compile Include="Host\StandbyModeTests.cs" />
     <Compile Include="Host\WebScriptHostManagerTests.cs" />
+    <Compile Include="ListenerFailureTests.cs" />
     <Compile Include="WindowsBatchEndToEndTests.cs" />
   </ItemGroup>
   <ItemGroup Condition="'$(OS)'!='Unix'">
     <Compile Include="PowerShellEndToEndTests.cs" />
   </ItemGroup>
   <ItemGroup>
+    <Content Include="TestScripts\ListenerExceptions\ListenerStartupException\index.js">
+      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
+    </Content>
+    <Content Include="TestScripts\ListenerExceptions\TimerTrigger\index.js">
+      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
+    </Content>
     <Content Include="TestScripts\Node\ApiHubTableEntityIn\index.js">
       <CopyToOutputDirectory>Always</CopyToOutputDirectory>
     </Content>
@@ -566,6 +573,15 @@
     <None Include="TestScripts\DotNet\host.json">
       <CopyToOutputDirectory>Always</CopyToOutputDirectory>
     </None>
+    <Content Include="TestScripts\ListenerExceptions\host.json">
+      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
+    </Content>
+    <Content Include="TestScripts\ListenerExceptions\ListenerStartupException\function.json">
+      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
+    </Content>
+    <Content Include="TestScripts\ListenerExceptions\TimerTrigger\function.json">
+      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
+    </Content>
     <None Include="TestScripts\Node\HttpTriggerShared\function.json">
       <CopyToOutputDirectory>Always</CopyToOutputDirectory>
     </None>