[V1 port] Record function pass/fail metrics. Fixes #3640

Author: alrod

src/WebJobs.Script/Description/FunctionInvokerBase.cs

@@ -259,6 +259,8 @@ public void End(bool success)
             _logInfo.LogFunctionResult(success, _metadata.Name, _invocationId.ToString(), _invocationStopWatch.ElapsedMilliseconds);
 
             startedEvent.Success = success;
+            string eventName = success ? MetricEventNames.FunctionInvokeSucceeded : MetricEventNames.FunctionInvokeFailed;
+            _metrics.LogEvent(eventName, startedEvent.FunctionName);
             _metrics.EndEvent(startedEvent);
 
             if (invokeLatencyEvent != null)

src/WebJobs.Script/Diagnostics/MetricEventNames.cs

@@ -21,5 +21,7 @@ public static class MetricEventNames
         public const string FunctionBindingTypeDirectionFormat = "function.binding.{0}.{1}";
         public const string FunctionCompileLatencyByLanguageFormat = "function.compile.{0}.latency";
         public const string FunctionInvokeThrottled = "function.invoke.throttled";
+        public const string FunctionInvokeSucceeded = "function.invoke.succeeded";
+        public const string FunctionInvokeFailed = "function.invoke.failed";
     }
 }

test/WebJobs.Script.Tests/Description/FunctionInvokerBaseTests.cs

@@ -115,6 +115,9 @@ public async Task Invoke_Success_EmitsExpectedEvents()
             var message = _traceWriter.GetTraces().Last().Message;
             Assert.True(Regex.IsMatch(message, $"Function completed \\(Success, Id={executionContext.InvocationId}, Duration=[0-9]*ms\\)"));
 
+            // verify invoke failed event
+            Assert.False(string.IsNullOrEmpty(_metricsLogger.LoggedEvents.FirstOrDefault(e => e == MetricEventNames.FunctionInvokeSucceeded)));
+
             // verify latency event
             var startLatencyEvent = _metricsLogger.EventsBegan[0];
             Assert.Equal($"{MetricEventNames.FunctionInvokeLatency}_testfunction", startLatencyEvent);
@@ -185,6 +188,9 @@ await Assert.ThrowsAsync<InvalidOperationException>(async () =>
             var message = _traceWriter.GetTraces().Last().Message;
             Assert.True(Regex.IsMatch(message, $"Function completed \\(Failure, Id={executionContext.InvocationId}, Duration=[0-9]*ms\\)"));
 
+            // verify invoke failed event
+            Assert.False(string.IsNullOrEmpty(_metricsLogger.LoggedEvents.FirstOrDefault(e => e == MetricEventNames.FunctionInvokeFailed)));
+
             // verify latency event
             var startLatencyEvent = _metricsLogger.EventsBegan[0];
             Assert.Equal($"{MetricEventNames.FunctionInvokeLatency}_testfunction", startLatencyEvent);