Very simple log appender

CodexNetDownloader/Configuration.cs

@@ -15,6 +15,9 @@ namespace CodexNetDownloader
         [Uniform("kube-config", "kc", "KUBECONFIG", true, "Path to Kubeconfig file. Use 'null' (default) to use local cluster.")]
         public string KubeConfigFile { get; set; } = "null";
 
+        [Uniform("continuous", "c", "CONTINUOUS", false, "If true, will continuously download and append log files.")]
+        public bool Continuous { get; set; } = false;
+
         public CodexDeployment CodexDeployment { get; set; } = null!;
 
         public TestRunnerLocation RunnerLocation { get; set; } = TestRunnerLocation.InternalToCluster;

CodexNetDownloader/ContinuousLogDownloader.cs

@@ -0,0 +1,84 @@
+using DistTestCore;
+using KubernetesWorkflow;
+
+namespace CodexNetDownloader
+{
+    public class ContinuousLogDownloader
+    {
+        private readonly TestLifecycle lifecycle;
+        private readonly Configuration config;
+
+        public ContinuousLogDownloader(TestLifecycle lifecycle, Configuration config)
+        {
+            this.lifecycle = lifecycle;
+            this.config = config;
+        }
+
+        public void Run()
+        {
+            while (true)
+            {
+                UpdateLogs();
+
+                Thread.Sleep(TimeSpan.FromSeconds(30));
+            }
+        }
+
+        private void UpdateLogs()
+        {
+            Console.WriteLine("Updating logs...");
+            foreach (var container in config.CodexDeployment.CodexContainers)
+            {
+                UpdateLog(container);
+            }
+        }
+
+        private void UpdateLog(RunningContainer container)
+        {
+            var filepath = Path.Combine(config.OutputPath, GetLogName(container));
+            if (!File.Exists(filepath)) File.WriteAllLines(filepath, new[] { "" });
+
+            var appender = new LogAppender(filepath);
+
+            lifecycle.CodexStarter.DownloadLog(container, appender);
+        }
+
+        private static string GetLogName(RunningContainer container)
+        {
+            return container.Name
+                .Replace("<","")
+                .Replace(">", "")
+                + ".log";
+        }
+    }
+
+    public class LogAppender : ILogHandler
+    {
+        private readonly string filename;
+
+        public LogAppender(string filename)
+        {
+            this.filename = filename;
+        }
+
+        public void Log(Stream log)
+        {
+            using var reader = new StreamReader(log);
+            var currentLines = File.ReadAllLines(filename);
+            var line = reader.ReadLine();
+            while (line != null)
+            {
+                AppendLineIfNew(line, currentLines);
+                line = reader.ReadLine();
+            }
+        }
+
+        private void AppendLineIfNew(string line, string[] currentLines)
+        {
+            if (!currentLines.Contains(line))
+            {
+                File.AppendAllLines(filename, new[] { line });
+            }
+        }
+    }
+}

CodexNetDownloader/Program.cs

@@ -1,4 +1,5 @@
 using ArgsUniform;
+using CodexNetDownloader;
 using ContinuousTests;
 using DistTestCore;
 using DistTestCore.Codex;
@@ -27,6 +28,13 @@ public class Program
         var k8sFactory = new K8sFactory();
         var (_, lifecycle) = k8sFactory.CreateFacilities(config.KubeConfigFile, config.OutputPath, "dataPath", config.CodexDeployment.Metadata.KubeNamespace, new DefaultTimeSet(), new NullLog(), config.RunnerLocation);
 
+        if (config.Continuous)
+        {
+            var dl = new ContinuousLogDownloader(lifecycle, config);
+            dl.Run();
+        }
+        else
+        {
             foreach (var container in config.CodexDeployment.CodexContainers)
             {
                 lifecycle.DownloadLog(container);
@@ -34,6 +42,7 @@ public class Program
 
             Console.WriteLine("Done!");
         }
+    }
 
     private static CodexDeployment ParseCodexDeploymentJson(string filename)
     {