Added command-line improvements for schema exports. (#8466)

Author: michaelstaib

src/HotChocolate/AspNetCore/src/AspNetCore.CommandLine/Command/ExportCommand.cs

@@ -1,6 +1,7 @@
 using System.CommandLine;
 using System.Text;
 using HotChocolate.Execution;
+using HotChocolate.Execution.Configuration;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Hosting;
 
@@ -39,13 +40,26 @@ private static async Task ExecuteAsync(
         string? schemaName,
         CancellationToken cancellationToken)
     {
-        schemaName ??= ISchemaDefinition.DefaultName;
+        var provider = host.Services.GetRequiredService<IRequestExecutorProvider>();
 
-        var schema = await host.Services
-            .GetRequiredService<IRequestExecutorProvider>()
-            .GetExecutorAsync(schemaName, cancellationToken);
+        if (schemaName is null)
+        {
+            var schemaNames = provider.SchemaNames;
+
+            if(schemaNames.IsEmpty)
+            {
+                console.WriteLine("No schemas registered.");
+                return;
+            }
+
+            schemaName = schemaNames.Contains(ISchemaDefinition.DefaultName)
+                ? ISchemaDefinition.DefaultName
+                : schemaNames[1];
+        }
+
+        var executor = await provider.GetExecutorAsync(schemaName, cancellationToken);
 
-        var sdl = schema.Schema.ToString();
+        var sdl = executor.Schema.ToString();
 
         if (output is not null)
         {

src/HotChocolate/AspNetCore/src/AspNetCore.CommandLine/Command/ListCommand.cs

@@ -0,0 +1,47 @@
+using System.CommandLine;
+using HotChocolate.Execution;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Hosting;
+
+namespace HotChocolate.AspNetCore.CommandLine;
+
+/// <summary>
+/// The export command can be used to export the schema to a file.
+/// </summary>
+internal sealed class ListCommand : Command
+{
+    /// <summary>
+    /// Initializes a new instance of the <see cref="ExportCommand"/> class.
+    /// </summary>
+    public ListCommand() : base("list")
+    {
+        Description = "List all registered GraphQL schemas.";
+
+        this.SetHandler(
+            ExecuteAsync,
+            Bind.FromServiceProvider<IConsole>(),
+            Bind.FromServiceProvider<IHost>(),
+            Bind.FromServiceProvider<CancellationToken>());
+    }
+
+    private static Task ExecuteAsync(
+        IConsole console,
+        IHost host,
+        CancellationToken cancellationToken)
+    {
+        var schemaNames = host.Services.GetRequiredService<IRequestExecutorProvider>().SchemaNames;
+
+        if(schemaNames.IsEmpty)
+        {
+            console.WriteLine("No schemas registered.");
+            return Task.CompletedTask;
+        }
+
+        foreach (var name in schemaNames)
+        {
+            console.WriteLine(name);
+        }
+
+        return Task.CompletedTask;
+    }
+}

src/HotChocolate/AspNetCore/src/AspNetCore.CommandLine/Command/SchemaCommand.cs

@@ -15,5 +15,6 @@ public SchemaCommand() : base("schema")
         Description = "Schema management commands.";
 
         AddCommand(new ExportCommand());
+        AddCommand(new ListCommand());
     }
 }

src/HotChocolate/AspNetCore/src/AspNetCore.CommandLine/WebApplicationExtensions.cs

@@ -92,6 +92,13 @@ public static void RunWithGraphQLCommands(
         }
     }
 
-    private static bool IsGraphQLCommand(this string[] args)
+    /// <summary>
+    /// Checks if the provided arguments are a GraphQL command.
+    /// </summary>
+    /// <param name="args">The command line arguments.</param>
+    /// <returns>
+    /// Returns <see langword="true"/> if the arguments are a GraphQL command; otherwise, <see langword="false"/>.
+    /// </returns>
+    public static bool IsGraphQLCommand(this string[] args)
         => args is ["schema", ..];
 }

src/HotChocolate/AspNetCore/test/AspNetCore.CommandLine.Tests/SchemaExportCommandTests.cs

@@ -49,7 +49,7 @@ public async Task App_Should_PrintSchema_When_OutputNotSpecified()
     }
 
     [Fact]
-    public async Task App_Should_WriteSchemaToFile_When_OutputOptionIsSpecfied()
+    public async Task App_Should_WriteSchemaToFile_When_OutputOptionIsSpecified()
     {
         // arrange
         var services = new ServiceCollection();

src/HotChocolate/AspNetCore/test/AspNetCore.CommandLine.Tests/SchemaListCommandTests.cs

@@ -0,0 +1,35 @@
+using HotChocolate.Types;
+using System.CommandLine.IO;
+using System.CommandLine.Parsing;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Hosting;
+using Moq;
+
+namespace HotChocolate.AspNetCore.CommandLine;
+
+public class SchemaListCommandTests
+{
+    [Fact]
+    public async Task App_Should_List_All_SchemaNames()
+    {
+        // arrange
+        var services = new ServiceCollection();
+        services.AddGraphQL()
+            .AddQueryType(x => x.Name("Query").Field("foo").Resolve("bar"));
+
+        var hostMock = new Mock<IHost>();
+        hostMock
+            .Setup(x => x.Services)
+            .Returns(services.BuildServiceProvider());
+
+        var host = hostMock.Object;
+        var console = new TestConsole();
+        var app = new App(host).Build();
+
+        // act
+        await app.InvokeAsync("schema list", console);
+
+        // assert
+        console.Out.ToString().MatchSnapshot();
+    }
+}

src/HotChocolate/AspNetCore/test/AspNetCore.CommandLine.Tests/__snapshots__/SchemaCommandTests.App_Should_OutputCorrectHelpTest_When_HelpIsRequested.snap

@@ -9,4 +9,5 @@ Options:
 
 Commands:
   export  Export the graphql schema. If no output (--output) is specified the schema will be printed to the console.
+  list    List all registered GraphQL schemas.
 

src/HotChocolate/AspNetCore/test/AspNetCore.CommandLine.Tests/__snapshots__/SchemaExportCommandTests.App_Should_WriteSchemaToFile_When_OutputOptionIsSpecfied.snap renamed to src/HotChocolate/AspNetCore/test/AspNetCore.CommandLine.Tests/__snapshots__/SchemaExportCommandTests.App_Should_WriteSchemaToFile_When_OutputOptionIsSpecified.snap

@@ -0,0 +1 @@
+_Default

src/HotChocolate/AspNetCore/test/AspNetCore.CommandLine.Tests/__snapshots__/SchemaListCommandTests.App_Should_List_All_SchemaNames.snap

@@ -1,7 +1,29 @@
+using System.Collections.Immutable;
+
 namespace HotChocolate.Execution;
 
+/// <summary>
+/// Represents a provider for GraphQL request executors.
+/// </summary>
 public interface IRequestExecutorProvider
 {
+    /// <summary>
+    /// Gets the names of all registered schemas.
+    /// </summary>
+    ImmutableArray<string> SchemaNames { get; }
+
+    /// <summary>
+    /// Gets a GraphQL request executor for the given schema name.
+    /// </summary>
+    /// <param name="schemaName">
+    /// The name of the schema to get an executor for.
+    /// </param>
+    /// <param name="cancellationToken">
+    /// The cancellation token.
+    /// </param>
+    /// <returns>
+    /// Returns a GraphQL request executor.
+    /// </returns>
     public ValueTask<IRequestExecutor> GetExecutorAsync(
         string? schemaName = null,
         CancellationToken cancellationToken = default);