feat: allow head method for MapQuery()

src/Cnblogs.Architecture.Ddd.Cqrs.AspNetCore/CqrsRouteMapper.cs

@@ -18,13 +18,16 @@ public static class CqrsRouteMapper
 
     private static readonly List<Type> CommandTypes = new() { typeof(ICommand<>), typeof(ICommand<,>) };
 
+    private static readonly string[] GetAndHeadMethods = { "GET", "HEAD" };
+
     /// <summary>
     ///     Map a query API, using GET method. <typeparamref name="T"/> would been constructed from route and query string.
     /// </summary>
     /// <param name="app"><see cref="IApplicationBuilder"/></param>
     /// <param name="route">The route template for API.</param>
     /// <param name="mapNullableRouteParameters">Multiple routes should be mapped when for nullable route parameters.</param>
     /// <param name="nullRouteParameterPattern">Replace route parameter with given string to represent null.</param>
+    /// <param name="enableHead">Map HEAD method for the same routes.</param>
     /// <typeparam name="T">The type of the query.</typeparam>
     /// <returns></returns>
     /// <example>
@@ -44,13 +47,15 @@ public static IEndpointConventionBuilder MapQuery<T>(
         this IEndpointRouteBuilder app,
         [StringSyntax("Route")] string route,
         MapNullableRouteParameter mapNullableRouteParameters = MapNullableRouteParameter.Disable,
-        string nullRouteParameterPattern = "-")
+        string nullRouteParameterPattern = "-",
+        bool enableHead = false)
     {
         return app.MapQuery(
             route,
             ([AsParameters] T query) => query,
             mapNullableRouteParameters,
-            nullRouteParameterPattern);
+            nullRouteParameterPattern,
+            enableHead);
     }
 
     /// <summary>
@@ -61,6 +66,7 @@ public static IEndpointConventionBuilder MapQuery<T>(
     /// <param name="handler">The delegate that returns a <see cref="IQuery{TView}"/> instance.</param>
     /// <param name="mapNullableRouteParameters">Multiple routes should be mapped when for nullable route parameters.</param>
     /// <param name="nullRouteParameterPattern">Replace route parameter with given string to represent null.</param>
+    /// <param name="enableHead">Allow HEAD for the same routes.</param>
     /// <returns></returns>
     /// <example>
     /// The following code:
@@ -80,7 +86,8 @@ public static IEndpointConventionBuilder MapQuery(
         [StringSyntax("Route")] string route,
         Delegate handler,
         MapNullableRouteParameter mapNullableRouteParameters = MapNullableRouteParameter.Disable,
-        string nullRouteParameterPattern = "-")
+        string nullRouteParameterPattern = "-",
+        bool enableHead = false)
     {
         var isQuery = handler.Method.ReturnType.GetInterfaces().Where(x => x.IsGenericType)
             .Any(x => QueryTypes.Contains(x.GetGenericTypeDefinition()));
@@ -92,7 +99,7 @@ public static IEndpointConventionBuilder MapQuery(
 
         if (mapNullableRouteParameters is MapNullableRouteParameter.Disable)
         {
-            return app.MapGet(route, handler).AddEndpointFilter<QueryEndpointHandler>();
+            return MapRoutes(route);
         }
 
         if (string.IsNullOrWhiteSpace(nullRouteParameterPattern))
@@ -125,10 +132,16 @@ public static IEndpointConventionBuilder MapQuery(
                     var regex = new Regex("{" + x.Name + "[^}]*?}", RegexOptions.IgnoreCase);
                     return regex.Replace(r, nullRouteParameterPattern);
                 });
-            app.MapGet(newRoute, handler).AddEndpointFilter<QueryEndpointHandler>();
+            MapRoutes(newRoute);
         }
 
-        return app.MapGet(route, handler).AddEndpointFilter<QueryEndpointHandler>();
+        return MapRoutes(route);
+
+        IEndpointConventionBuilder MapRoutes(string r)
+        {
+            var endpoint = enableHead ? app.MapMethods(r, GetAndHeadMethods, handler) : app.MapGet(r, handler);
+            return endpoint.AddEndpointFilter<QueryEndpointHandler>();
+        }
     }
 
     /// <summary>

src/Cnblogs.Architecture.Ddd.Cqrs.ServiceAgent/CqrsServiceAgent.cs

@@ -146,6 +146,29 @@ public async Task<CommandResponse<TResponse, ServiceAgentError>> PutCommandAsync
         }
     }
 
+    /// <summary>
+    ///     Query item with HEAD method.
+    /// </summary>
+    /// <param name="url">The route of the API.</param>
+    /// <returns>True if status code is 2xx, False if status code is 404.</returns>
+    public async Task<bool> HasItemAsync(string url)
+    {
+        var request = new HttpRequestMessage(HttpMethod.Head, url);
+        var response = await HttpClient.SendAsync(request);
+        if (response.IsSuccessStatusCode)
+        {
+            return true;
+        }
+
+        if (response.StatusCode == HttpStatusCode.NotFound)
+        {
+            return false;
+        }
+
+        response.EnsureSuccessStatusCode(); // throw for other status code
+        return false;
+    }
+
     /// <summary>
     ///     Batch get items with GET method.
     /// </summary>

test/Cnblogs.Architecture.IntegrationTestProject/Program.cs

@@ -35,7 +35,7 @@
 
 var apis = app.NewVersionedApi();
 var v1 = apis.MapGroup("/api/v{version:apiVersion}").HasApiVersion(1);
-v1.MapQuery<GetStringQuery>("apps/{appId}/strings/{stringId:int}/value", MapNullableRouteParameter.Enable);
+v1.MapQuery<GetStringQuery>("apps/{appId}/strings/{stringId:int}/value", MapNullableRouteParameter.Enable, enableHead: true);
 v1.MapQuery<GetStringQuery>("strings/{id:int}");
 v1.MapQuery<ListStringsQuery>("strings");
 v1.MapCommand("strings", (CreatePayload payload) => new CreateCommand(payload.NeedError));

test/Cnblogs.Architecture.IntegrationTests/CqrsRouteMapperTests.cs

@@ -96,4 +96,26 @@ await builder.CreateClient().GetAsync("/api/v1/apps/someApp/strings/1/value")
         // Assert
         responses.Should().Match(x => x.All(y => y.IsSuccessStatusCode));
     }
+
+    [Fact]
+    public async Task GetItem_MapHeadAndGet_SuccessAsync()
+    {
+        // Arrange
+        var builder = new WebApplicationFactory<Program>();
+
+        // Act
+        var uris = new[]
+        {
+            "/api/v1/apps/-/strings/-/value", "/api/v1/apps/-/strings/1/value",
+            "/api/v1/apps/someApp/strings/-/value", "/api/v1/apps/someApp/strings/1/value"
+        }.Select(x => new HttpRequestMessage(HttpMethod.Head, x));
+        var responses = new List<HttpResponseMessage>();
+        foreach (var uri in uris)
+        {
+            responses.Add(await builder.CreateClient().SendAsync(uri, HttpCompletionOption.ResponseHeadersRead));
+        }
+
+        // Assert
+        responses.Should().Match(x => x.All(y => y.IsSuccessStatusCode));
+    }
 }