Use RunOnce for jobs that maintain their own loop (#487)

Progress on NuGet/Engineering#1543

Author: joelverhagen

src/NuGet.Jobs.Common/JobRunner.cs

@@ -91,7 +91,16 @@ private static async Task Run(JobBase job, string[] commandLineArgs, bool? runCo
                 // Configure our logging again with Application Insights initialized.
                 loggerFactory = ConfigureLogging(job);
 
-                runContinuously = runContinuously ?? !JobConfigurationManager.TryGetBoolArgument(jobArgsDictionary, JobArgumentNames.Once);
+                var hasOnceArgument = JobConfigurationManager.TryGetBoolArgument(jobArgsDictionary, JobArgumentNames.Once);
+
+                if (runContinuously.HasValue && hasOnceArgument)
+                {
+                    _logger.LogWarning(
+                        $"This job is designed to {(runContinuously.Value ? "run continuously" : "run once")} so " +
+                        $"the -{JobArgumentNames.Once} argument is {(runContinuously.Value ? "ignored" : "redundant")}.");
+                }
+
+                runContinuously = runContinuously ?? !hasOnceArgument;
                 var reinitializeAfterSeconds = JobConfigurationManager.TryGetIntArgument(jobArgsDictionary, JobArgumentNames.ReinitializeAfterSeconds);
                 var sleepDuration = JobConfigurationManager.TryGetIntArgument(jobArgsDictionary, JobArgumentNames.Sleep); // sleep is in milliseconds
 
@@ -104,18 +113,34 @@ private static async Task Run(JobBase job, string[] commandLineArgs, bool? runCo
                     }
                 }
 
-                if (sleepDuration == null)
+                if (!sleepDuration.HasValue)
                 {
-                    _logger.LogInformation("SleepDuration is not provided or is not a valid integer. Unit is milliSeconds. Assuming default of 5000 ms...");
+                    if (runContinuously.Value)
+                    {
+                        _logger.LogInformation("SleepDuration is not provided or is not a valid integer. Unit is milliSeconds. Assuming default of 5000 ms...");
+                    }
+                    
                     sleepDuration = 5000;
                 }
+                else if (!runContinuously.Value)
+                {
+                    _logger.LogWarning(
+                        $"The job is designed to run once so the -{JobArgumentNames.Sleep} and " +
+                        $"-{JobArgumentNames.Interval} arguments are ignored.");
+                }
 
                 if (!reinitializeAfterSeconds.HasValue)
                 {
                     _logger.LogInformation(
                         $"{JobArgumentNames.ReinitializeAfterSeconds} command line argument is not provided or is not a valid integer. " +
                         "The job will reinitialize on every iteration");
                 }
+                else if (!runContinuously.Value)
+                {
+                    _logger.LogWarning(
+                        $"The job is designed to run once so the -{JobArgumentNames.ReinitializeAfterSeconds} " +
+                        $"argument is ignored.");
+                }
 
                 // Ensure that SSLv3 is disabled and that Tls v1.2 is enabled.
                 ServicePointManager.SecurityProtocol &= ~SecurityProtocolType.Ssl3;

src/NuGet.Services.Validation.Orchestrator/Program.cs

@@ -1,7 +1,6 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
-using System.Linq;
 using NuGet.Jobs;
 
 namespace NuGet.Services.Validation.Orchestrator
@@ -10,12 +9,8 @@ class Program
     {
         static int Main(string[] args)
         {
-            if (!args.Contains(JobArgumentNames.Once))
-            {
-                args = args.Concat(new[] { "-" + JobArgumentNames.Once }).ToArray();
-            }
             var job = new Job();
-            JobRunner.Run(job, args).GetAwaiter().GetResult();
+            JobRunner.RunOnce(job, args).GetAwaiter().GetResult();
 
             // if configuration validation failed, return non-zero status so we can detect failures in automation
             return job.ConfigurationValidated ? 0 : 1;

src/Validation.PackageSigning.ProcessSignature/Program.cs

@@ -8,7 +8,7 @@ public class Program
         public static void Main(string[] args)
         {
             var job = new Job();
-            JobRunner.Run(job, args).GetAwaiter().GetResult();
+            JobRunner.RunOnce(job, args).GetAwaiter().GetResult();
         }
     }
 }

src/Validation.PackageSigning.ValidateCertificate/Program.cs

@@ -10,7 +10,7 @@ class Program
         static void Main(string[] args)
         {
             var job = new Job();
-            JobRunner.Run(job, args).GetAwaiter().GetResult();
+            JobRunner.RunOnce(job, args).GetAwaiter().GetResult();
         }
     }
 }