Parameter examples with APIWeaver

Author: Tsingis

App/Api/Api.csproj

@@ -1,5 +1,6 @@
 <Project Sdk="Microsoft.NET.Sdk.Web">
   <ItemGroup>
+    <PackageReference Include="APIWeaver.OpenApi" />
     <ProjectReference Include="..\Services\Services.csproj" />
     <PackageReference Include="Asp.Versioning.Mvc.ApiExplorer" />
     <PackageReference Include="Microsoft.AspNetCore.OpenApi" />

App/Api/Setup/ApiEndpoints.cs

@@ -8,9 +8,6 @@ namespace Api.Setup;
 
 internal static class ApiEndpoints
 {
-    private static readonly OpenApiString s_exampleFromDate = new(DateTime.Now.AddMonths(-1).ToString("yyyy-MM-dd", CultureInfo.InvariantCulture));
-    private static readonly OpenApiString s_exampleToDate = new(DateTime.Now.ToString("yyyy-MM-dd", CultureInfo.InvariantCulture));
-
     public static void ConfigureEndpoints(this WebApplication app)
     {
         var apiVersionSet = app.NewApiVersionSet()
@@ -42,8 +39,8 @@ public static void ConfigureEndpoints(this WebApplication app)
             .WithDescription("Get longest downward trend in days between given dates")
             .WithOpenApi(operation =>
             {
-                operation.Parameters[0].Example = s_exampleFromDate;
-                operation.Parameters[^1].Example = s_exampleToDate;
+                operation.Parameters[0].Example = GetExampleString(-1);
+                operation.Parameters[^1].Example = GetExampleString();
                 return operation;
             })
             .Produces<HighestTradingVolumeResponse>((int)HttpStatusCode.OK)
@@ -76,8 +73,8 @@ public static void ConfigureEndpoints(this WebApplication app)
             .WithDescription("Get the date with the highest trading volume between given dates")
             .WithOpenApi(operation =>
             {
-                operation.Parameters[0].Example = s_exampleFromDate;
-                operation.Parameters[^1].Example = s_exampleToDate;
+                operation.Parameters[0].Example = GetExampleString(-1);
+                operation.Parameters[^1].Example = GetExampleString();
                 return operation;
             })
             .Produces<HighestTradingVolumeResponse>((int)HttpStatusCode.OK)
@@ -110,8 +107,8 @@ public static void ConfigureEndpoints(this WebApplication app)
             .WithDescription("Get pair of dates when it is best to buy and sell between given dates")
             .WithOpenApi(operation =>
             {
-                operation.Parameters[0].Example = s_exampleFromDate;
-                operation.Parameters[^1].Example = s_exampleToDate;
+                operation.Parameters[0].Example = GetExampleString(-1);
+                operation.Parameters[^1].Example = GetExampleString();
                 return operation;
             })
             .Produces<BuyAndSellResponse>((int)HttpStatusCode.OK)
@@ -120,6 +117,11 @@ public static void ConfigureEndpoints(this WebApplication app)
             .ProducesProblem((int)HttpStatusCode.TooManyRequests)
             .ProducesProblem((int)HttpStatusCode.InternalServerError);
     }
+
+    private static OpenApiString GetExampleString(int addMonths = 0)
+    {
+        return new(DateOnlyExampleProvider.GetExample().AddMonths(addMonths).ToString("yyyy-MM-dd", CultureInfo.InvariantCulture));
+    }
 }
 
 public record LongestDownwardTrendResponse(int Days);

App/Api/Setup/ApiServices.cs

@@ -1,6 +1,7 @@
 using System.Text.Json;
 using System.Text.Json.Serialization;
 using System.Threading.RateLimiting;
+using APIWeaver;
 using Asp.Versioning;
 using Microsoft.AspNetCore.Http.Json;
 using Microsoft.AspNetCore.Server.Kestrel.Core;
@@ -30,6 +31,11 @@ public static void ConfigureServices(this IServiceCollection services)
 
         services.AddOpenApi();
 
+        services.AddApiWeaver(opt =>
+        {
+            opt.AddExample<DateOnly, DateOnlyExampleProvider>();
+        });
+
         services.AddSwaggerGen();
 
         services.Configure<JsonOptions>(opt =>

App/Api/Setup/DateOnlyExampleProvider.cs

@@ -0,0 +1,8 @@
+using APIWeaver;
+
+namespace Api.Setup;
+
+public sealed class DateOnlyExampleProvider : IExampleProvider<DateOnly>
+{
+    public static DateOnly GetExample() => DateOnly.FromDateTime(DateTime.UtcNow);
+}

App/Directory.Packages.props

@@ -4,6 +4,7 @@
     <CentralPackageTransitivePinningEnabled>true</CentralPackageTransitivePinningEnabled>
   </PropertyGroup>
   <ItemGroup>
+    <PackageVersion Include="APIWeaver.OpenApi" Version="2.7.0" />
     <PackageVersion Include="Asp.Versioning.Mvc.ApiExplorer" Version="8.1.0" />
     <PackageVersion Include="Microsoft.AspNetCore.OpenApi" Version="9.0.4" />
     <PackageVersion Include="Microsoft.AspNetCore.WebUtilities" Version="9.0.4" />