From e7d059ceed480020b52d4e9cecfabf467b0e271a Mon Sep 17 00:00:00 2001
From: benbierens <thatbenbierens@gmail.com>
Date: Fri, 2 Jun 2023 09:03:46 +0200
Subject: [PATCH] Makes default configuration overridable from environment
 variables.

---
 DistTestCore/Configuration.cs | 46 +++++++++++++++++++++++++++++++----
 README.md                     | 11 +++++++++
 2 files changed, 52 insertions(+), 5 deletions(-)

diff --git a/DistTestCore/Configuration.cs b/DistTestCore/Configuration.cs
index b9f21de3..f66c39db 100644
--- a/DistTestCore/Configuration.cs
+++ b/DistTestCore/Configuration.cs
@@ -5,11 +5,28 @@ namespace DistTestCore
 {
     public class Configuration
     {
+        private readonly string? kubeConfigFile;
+        private readonly string logPath;
+        private readonly bool logDebug;
+        private readonly string dataFilesPath;
+        private readonly CodexLogLevel codexLogLevel;
+        private readonly TestRunnerLocation runnerLocation;
+
+        public Configuration()
+        {
+            kubeConfigFile = GetNullableEnvVarOrDefault("KUBECONFIG", null);
+            logPath = GetEnvVarOrDefault("LOGPATH", "CodexTestLogs");
+            logDebug = GetEnvVarOrDefault("LOGDEBUG", "false").ToLowerInvariant() == "true";
+            dataFilesPath = GetEnvVarOrDefault("DATAFILEPATH", "TestDataFiles");
+            codexLogLevel = ParseEnum<CodexLogLevel>(GetEnvVarOrDefault("LOGLEVEL", nameof(CodexLogLevel.Trace)));
+            runnerLocation = ParseEnum<TestRunnerLocation>(GetEnvVarOrDefault("RUNNERLOCATION", nameof(TestRunnerLocation.ExternalToCluster)));
+        }
+
         public KubernetesWorkflow.Configuration GetK8sConfiguration(ITimeSet timeSet)
         {
             return new KubernetesWorkflow.Configuration(
                 k8sNamespacePrefix: "ct-",
-                kubeConfigFile: null,
+                kubeConfigFile: kubeConfigFile,
                 operationTimeout: timeSet.K8sOperationTimeout(),
                 retryDelay: timeSet.WaitForK8sServiceDelay(),
                 locationMap: new[]
@@ -22,22 +39,22 @@ namespace DistTestCore
 
         public Logging.LogConfig GetLogConfig()
         {
-            return new Logging.LogConfig("CodexTestLogs", debugEnabled: false);
+            return new Logging.LogConfig(logPath, debugEnabled: logDebug);
         }
 
         public string GetFileManagerFolder()
         {
-            return "TestDataFiles";
+            return dataFilesPath;
         }
 
         public CodexLogLevel GetCodexLogLevel()
         {
-            return CodexLogLevel.Trace;
+            return codexLogLevel;
         }
 
         public TestRunnerLocation GetTestRunnerLocation()
         {
-            return TestRunnerLocation.ExternalToCluster;
+            return runnerLocation;
         }
 
         public RunningContainerAddress GetAddress(RunningContainer container)
@@ -48,6 +65,25 @@ namespace DistTestCore
             }
             return container.ClusterExternalAddress;
         }
+
+        private static string GetEnvVarOrDefault(string varName, string defaultValue)
+        {
+            var v = Environment.GetEnvironmentVariable(varName);
+            if (v == null) return defaultValue;
+            return v;
+        }
+
+        private static string? GetNullableEnvVarOrDefault(string varName, string? defaultValue)
+        {
+            var v = Environment.GetEnvironmentVariable(varName);
+            if (v == null) return defaultValue;
+            return v;
+        }
+
+        private static T ParseEnum<T>(string value)
+        {
+            return (T)Enum.Parse(typeof(T), value, true);
+        }
     }
 
     public enum TestRunnerLocation
diff --git a/README.md b/README.md
index 9f5ebefd..4d4760c0 100644
--- a/README.md
+++ b/README.md
@@ -17,6 +17,17 @@ Tests are devided into two assemblies: `/Tests` and `/LongTests`.
 
 TODO: All tests will eventually be running as part of a dedicated CI pipeline and kubernetes cluster. Currently, we're developing these tests and the infra-code to support it by running the whole thing locally.
 
+## Configuration
+Test executing can be configured using the following environment variables.
+| Variable       | Description                                                                                                                                          | Default             |
+|----------------|------------------------------------------------------------------------------------------------------------------------------------------------------|---------------------|
+| KUBECONFIG     | Optional path (abs or rel) to kubeconfig YAML file. When null, uses system default (docker-desktop) kubeconfig if available.                         | (null)              |
+| LOGPATH        | Path (abs or rel) where log files will be saved.                                                                                                     | "CodexTestLogs"     |
+| LOGDEBUG       | When "true", enables additional test-runner debug log output.                                                                                                    | "false"             |
+| DATAFILEPATH   | Path (abs or rel) where temporary test data files will be saved.                                                                                     | "TestDataFiles"     |
+| LOGLEVEL       | Codex log-level. (case-insensitive)                                                                                                                  | "Trace"             |
+| RUNNERLOCATION | Use "ExternalToCluster" when test app is running outside of the k8s cluster. Use "InternalToCluster" when tests are run from inside a pod/container. | "ExternalToCluster" |
+
 ## Test logs
 Because tests potentially take a long time to run, logging is in place to help you investigate failures afterwards. Should a test fail, all Codex terminal output (as well as metrics if they have been enabled) will be downloaded and stored along with a detailed, step-by-step log of the test. If something's gone wrong and you're here to discover the details, head for the logs.