Set OpenApiServers object in document

src/OpenApi/src/Services/OpenApiDocumentService.cs

@@ -9,6 +9,8 @@
 using System.IO.Pipelines;
 using System.Linq;
 using System.Reflection;
+using Microsoft.AspNetCore.Hosting.Server;
+using Microsoft.AspNetCore.Hosting.Server.Features;
 using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.Http.Metadata;
 using Microsoft.AspNetCore.Mvc;
@@ -29,7 +31,8 @@ internal sealed class OpenApiDocumentService(
     IApiDescriptionGroupCollectionProvider apiDescriptionGroupCollectionProvider,
     IHostEnvironment hostEnvironment,
     IOptionsMonitor<OpenApiOptions> optionsMonitor,
-    IServiceProvider serviceProvider)
+    IServiceProvider serviceProvider,
+    IServer? server = null)
 {
     private readonly OpenApiOptions _options = optionsMonitor.Get(documentName);
     private readonly OpenApiSchemaService _componentService = serviceProvider.GetRequiredKeyedService<OpenApiSchemaService>(documentName);
@@ -58,6 +61,7 @@ public async Task<OpenApiDocument> GetOpenApiDocumentAsync(CancellationToken can
         {
             Info = GetOpenApiInfo(),
             Paths = await GetOpenApiPathsAsync(capturedTags, cancellationToken),
+            Servers = GetOpenApiServers(),
             Tags = [.. capturedTags]
         };
         await ApplyTransformersAsync(document, cancellationToken);
@@ -92,6 +96,16 @@ internal OpenApiInfo GetOpenApiInfo()
         };
     }
 
+    internal List<OpenApiServer> GetOpenApiServers()
+    {
+        if (hostEnvironment.IsDevelopment() &&
+            server?.Features.Get<IServerAddressesFeature>()?.Addresses is { Count: > 0 } addresses)
+        {
+            return addresses.Select(address => new OpenApiServer { Url = address }).ToList();
+        }
+        return [];
+    }
+
     /// <summary>
     /// Gets the OpenApiPaths for the document based on the ApiDescriptions.
     /// </summary>

src/OpenApi/test/Services/OpenApiDocumentService/OpenApiDocumentServiceTests.Info.cs

@@ -23,7 +23,8 @@ public void GetOpenApiInfo_RespectsHostEnvironmentName()
             new Mock<IApiDescriptionGroupCollectionProvider>().Object,
             hostEnvironment,
             new Mock<IOptionsMonitor<OpenApiOptions>>().Object,
-            new Mock<IKeyedServiceProvider>().Object);
+            new Mock<IKeyedServiceProvider>().Object,
+            new OpenApiTestServer());
 
         // Act
         var info = docService.GetOpenApiInfo();
@@ -45,7 +46,8 @@ public void GetOpenApiInfo_RespectsDocumentName()
             new Mock<IApiDescriptionGroupCollectionProvider>().Object,
             hostEnvironment,
             new Mock<IOptionsMonitor<OpenApiOptions>>().Object,
-            new Mock<IKeyedServiceProvider>().Object);
+            new Mock<IKeyedServiceProvider>().Object,
+            new OpenApiTestServer());
 
         // Act
         var info = docService.GetOpenApiInfo();

src/OpenApi/test/Services/OpenApiDocumentService/OpenApiDocumentServiceTests.Servers.cs

@@ -0,0 +1,109 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using Microsoft.AspNetCore.Mvc.ApiExplorer;
+using Microsoft.AspNetCore.OpenApi;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Hosting.Internal;
+using Microsoft.Extensions.Options;
+using Moq;
+
+public partial class OpenApiDocumentServiceTests
+{
+    [Fact]
+    public void GetOpenApiServers_HandlesServerAddressFeatureWithValues()
+    {
+        // Arrange
+        var hostEnvironment = new HostingEnvironment
+        {
+            ApplicationName = "TestApplication",
+            EnvironmentName = "Development"
+        };
+        var docService = new OpenApiDocumentService(
+            "v1",
+            new Mock<IApiDescriptionGroupCollectionProvider>().Object,
+            hostEnvironment,
+            new Mock<IOptionsMonitor<OpenApiOptions>>().Object,
+            new Mock<IKeyedServiceProvider>().Object,
+            new OpenApiTestServer(["http://localhost:5000"]));
+
+        // Act
+        var servers = docService.GetOpenApiServers();
+
+        // Assert
+        Assert.Contains("http://localhost:5000", servers.Select(s => s.Url));
+    }
+
+    [Fact]
+    public void GetOpenApiServers_HandlesServerAddressFeatureWithMultipleValues()
+    {
+        // Arrange
+        var hostEnvironment = new HostingEnvironment
+        {
+            ApplicationName = "TestApplication",
+            EnvironmentName = "Development"
+        };
+        var docService = new OpenApiDocumentService(
+            "v1",
+            new Mock<IApiDescriptionGroupCollectionProvider>().Object,
+            hostEnvironment,
+            new Mock<IOptionsMonitor<OpenApiOptions>>().Object,
+            new Mock<IKeyedServiceProvider>().Object,
+            new OpenApiTestServer(["http://localhost:5000", "http://localhost:5002"]));
+
+        // Act
+        var servers = docService.GetOpenApiServers();
+
+        // Assert
+        Assert.Contains("http://localhost:5000", servers.Select(s => s.Url));
+        Assert.Contains("http://localhost:5002", servers.Select(s => s.Url));
+    }
+
+    [Fact]
+    public void GetOpenApiServers_HandlesNonDevelopmentEnvironment()
+    {
+        // Arrange
+        var hostEnvironment = new HostingEnvironment
+        {
+            ApplicationName = "TestApplication",
+            EnvironmentName = "Production"
+        };
+        var docService = new OpenApiDocumentService(
+            "v1",
+            new Mock<IApiDescriptionGroupCollectionProvider>().Object,
+            hostEnvironment,
+            new Mock<IOptionsMonitor<OpenApiOptions>>().Object,
+            new Mock<IKeyedServiceProvider>().Object,
+            new OpenApiTestServer(["http://localhost:5000"]));
+
+        // Act
+        var servers = docService.GetOpenApiServers();
+
+        // Assert
+        Assert.Empty(servers);
+    }
+
+    [Fact]
+    public void GetOpenApiServers_HandlesServerAddressFeatureWithNoValues()
+    {
+        // Arrange
+        var hostEnvironment = new HostingEnvironment
+        {
+            ApplicationName = "TestApplication",
+            EnvironmentName = "Development"
+        };
+        var docService = new OpenApiDocumentService(
+            "v2",
+            new Mock<IApiDescriptionGroupCollectionProvider>().Object,
+            hostEnvironment,
+            new Mock<IOptionsMonitor<OpenApiOptions>>().Object,
+            new Mock<IKeyedServiceProvider>().Object,
+            new OpenApiTestServer());
+
+        // Act
+        var servers = docService.GetOpenApiServers();
+
+        // Assert
+        Assert.Empty(servers);
+    }
+}

src/OpenApi/test/Services/OpenApiDocumentServiceTestsBase.cs

@@ -3,6 +3,9 @@
 
 using System.Reflection;
 using Microsoft.AspNetCore.Builder;
+using Microsoft.AspNetCore.Hosting.Server;
+using Microsoft.AspNetCore.Hosting.Server.Features;
+using Microsoft.AspNetCore.Http.Features;
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.AspNetCore.Mvc.Abstractions;
 using Microsoft.AspNetCore.Mvc.ActionConstraints;
@@ -75,7 +78,7 @@ internal static OpenApiDocumentService CreateDocumentService(ActionDescriptor ac
 
         var schemaService = new OpenApiSchemaService("Test", Options.Create(new Microsoft.AspNetCore.Http.Json.JsonOptions()), builder.ServiceProvider, openApiOptions.Object);
         ((TestServiceProvider)builder.ServiceProvider).TestSchemaService = schemaService;
-        var documentService = new OpenApiDocumentService("Test", apiDescriptionGroupCollectionProvider, hostEnvironment, openApiOptions.Object, builder.ServiceProvider);
+        var documentService = new OpenApiDocumentService("Test", apiDescriptionGroupCollectionProvider, hostEnvironment, openApiOptions.Object, builder.ServiceProvider, new OpenApiTestServer());
         ((TestServiceProvider)builder.ServiceProvider).TestDocumentService = documentService;
 
         return documentService;
@@ -101,7 +104,7 @@ internal static OpenApiDocumentService CreateDocumentService(IEndpointRouteBuild
 
         var schemaService = new OpenApiSchemaService("Test", Options.Create(new Microsoft.AspNetCore.Http.Json.JsonOptions()), builder.ServiceProvider, options.Object);
         ((TestServiceProvider)builder.ServiceProvider).TestSchemaService = schemaService;
-        var documentService = new OpenApiDocumentService("Test", apiDescriptionGroupCollectionProvider, hostEnvironment, options.Object, builder.ServiceProvider);
+        var documentService = new OpenApiDocumentService("Test", apiDescriptionGroupCollectionProvider, hostEnvironment, options.Object, builder.ServiceProvider, new OpenApiTestServer());
         ((TestServiceProvider)builder.ServiceProvider).TestDocumentService = documentService;
 
         return documentService;
@@ -276,4 +279,31 @@ public object GetService(Type serviceType)
             return _serviceProvider.GetService(serviceType);
         }
     }
+
+    internal class OpenApiTestServer(string[] addresses = null) : IServer
+    {
+        public IFeatureCollection Features => GenerateFeatures();
+
+        public void Dispose()
+        {
+            return;
+        }
+
+        internal virtual IFeatureCollection GenerateFeatures()
+        {
+            var features = new FeatureCollection();
+            features.Set<IServerAddressesFeature>(new TestServerAddressesFeature { Addresses = addresses });
+            return features;
+        }
+
+        public Task StartAsync<TContext>(IHttpApplication<TContext> application, CancellationToken cancellationToken) where TContext : notnull => Task.CompletedTask;
+
+        public Task StopAsync(CancellationToken cancellationToken) => Task.CompletedTask;
+    }
+
+    private class TestServerAddressesFeature : IServerAddressesFeature
+    {
+        public ICollection<string> Addresses { get; set; }
+        public bool PreferHostingUrls { get; set; }
+    }
 }