Add support for getting secrets from environment variables when running tests (#10594)

Author: etvorun

tests/NuGetGallery.FunctionalTests.Core/EnvVarWrapperSecretReader.cs

@@ -0,0 +1,60 @@
+// 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;
+using System.Threading.Tasks;
+using Microsoft.Extensions.Logging;
+using NuGet.Services.KeyVault;
+
+namespace NuGetGallery.FunctionalTests
+{
+    class EnvVarWrapperSecretReader : ISecretReader
+    {
+        private readonly Lazy<ISecretReader> _secretReader;
+
+        public EnvVarWrapperSecretReader(ISecretReaderFactory factory) => _secretReader = new Lazy<ISecretReader>(factory.CreateSecretReader);
+        public Task<string> GetSecretAsync(string secretName)=> GetSecretAsync(secretName, logger: null);
+        public Task<ISecret> GetSecretObjectAsync(string secretName) => GetSecretObjectAsync(secretName, logger: null);
+
+        public Task<string> GetSecretAsync(string secretName, ILogger logger)
+        {
+            if (TryGetFromEnvironmentVariable(secretName, logger) is string envVarValue)
+            {
+                return Task.FromResult(envVarValue);
+            }
+
+            return _secretReader.Value.GetSecretAsync(secretName, logger);
+        }
+
+        public Task<ISecret> GetSecretObjectAsync(string secretName, ILogger logger)
+        {
+            if (TryGetFromEnvironmentVariable(secretName, logger) is string envVarValue)
+            {
+                ISecret result = new KeyVaultSecret(secretName, envVarValue, null);
+                return Task.FromResult(result);
+            }
+
+            return _secretReader.Value.GetSecretObjectAsync(secretName, logger);
+        }
+
+        private string TryGetFromEnvironmentVariable(string secretName, ILogger logger)
+        {
+            var message = $"Source of secret '{secretName}': ";
+            var envVarValue = Environment.GetEnvironmentVariable(secretName);
+            if (string.IsNullOrWhiteSpace(envVarValue))
+            {
+                message += "KEY VAULT";
+                envVarValue = null;
+            }
+            else
+            {
+                message += "ENV VAR";
+            }
+
+            logger?.LogInformation(message);
+            Console.WriteLine(message);
+
+            return envVarValue;
+        }
+    }
+}

tests/NuGetGallery.FunctionalTests.Core/GalleryConfiguration.cs

@@ -1,4 +1,4 @@
-// Copyright (c) .NET Foundation. All rights reserved.
+// 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;
@@ -46,7 +46,8 @@ static GalleryConfiguration()
 
                 // Initialize KeyVault integration.
                 var secretReaderFactory = new ConfigurationRootSecretReaderFactory(uninjectedConfiguration);
-                var secretInjector = secretReaderFactory.CreateSecretInjector(secretReaderFactory.CreateSecretReader());
+                var secretReader = new EnvVarWrapperSecretReader(secretReaderFactory);
+                var secretInjector = secretReaderFactory.CreateSecretInjector(secretReader);
 
                 // Initialize the configuration with KeyVault secrets injected.
                 var builder = new ConfigurationBuilder()