Require HttpContext only where needed instead of throwing on ctor

CHANGELOG.md

@@ -5,6 +5,14 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/)
 and this project adheres to [Semantic Versioning](http://semver.org/).
 
+## Unreleased
+
+### Changed
+
+- Require HttpContext in default `PaginationService` only where needed instead of throwing on ctor ([#11](https://github.com/mrahhal/MR.AspNetCore.Pagination/pull/11))
+
+[**Full diff**](https://github.com/mrahhal/MR.EntityFrameworkCore.KeysetPagination/compare/v2.2.0...HEAD)
+
 ## 2.2.0 - 2023-10-23
 
 ### Other

src/MR.AspNetCore.Pagination/PaginationService.cs

@@ -302,18 +302,18 @@ public static OffsetPaginationResult<T> OffsetPaginate<T>(
 /// </summary>
 public class PaginationService : IPaginationService
 {
-	private readonly HttpContext _httpContext;
 	private readonly PaginationOptions _options;
+	private readonly HttpContext? _httpContext;
 
 	/// <summary>
 	/// Creates a new instance of <see cref="PaginationService"/>.
 	/// </summary>
 	public PaginationService(
-		IHttpContextAccessor httpContextAccessor,
-		IOptions<PaginationOptions> options)
+		IOptions<PaginationOptions> options,
+		IHttpContextAccessor? httpContextAccessor = null)
 	{
-		_httpContext = httpContextAccessor?.HttpContext ?? throw new InvalidOperationException("HttpContext is required.");
 		_options = options.Value;
+		_httpContext = httpContextAccessor?.HttpContext;
 	}
 
 	/// <inheritdoc/>
@@ -429,7 +429,7 @@ public Task<KeysetPaginationResult<TOut>> KeysetPaginateAsync<T, TOut>(
 		where TOut : class
 	{
 		var queryModel = ParseKeysetQueryModel(
-			_httpContext.Request.Query,
+			GetHttpContextRequestQueryOrThrow(),
 			pageSize);
 		return KeysetPaginateAsync(source, keysetQueryDefinition, getReferenceAsync, map, queryModel);
 	}
@@ -445,7 +445,7 @@ public Task<KeysetPaginationResult<TOut>> KeysetPaginateAsync<T, TOut>(
 		where TOut : class
 	{
 		var queryModel = ParseKeysetQueryModel(
-			_httpContext.Request.Query,
+			GetHttpContextRequestQueryOrThrow(),
 			pageSize);
 		return KeysetPaginateAsync(source, builderAction, getReferenceAsync, map, queryModel);
 	}
@@ -487,7 +487,7 @@ public Task<OffsetPaginationResult<TOut>> OffsetPaginateAsync<T, TOut>(
 		where TOut : class
 	{
 		var queryModel = ParseOffsetQueryModel(
-			_httpContext.Request.Query,
+			GetHttpContextRequestQueryOrThrow(),
 			pageSize);
 		return OffsetPaginateAsync(source, map, queryModel);
 	}
@@ -529,7 +529,7 @@ public OffsetPaginationResult<TOut> OffsetPaginate<T, TOut>(
 		where TOut : class
 	{
 		var queryModel = ParseOffsetQueryModel(
-			_httpContext.Request.Query,
+			GetHttpContextRequestQueryOrThrow(),
 			pageSize);
 		return OffsetPaginate(source, map, queryModel);
 	}
@@ -660,4 +660,10 @@ private OffsetQueryModel ParseOffsetQueryModel(
 
 		return model;
 	}
+
+	private IQueryCollection GetHttpContextRequestQueryOrThrow()
+	{
+		var context = _httpContext ?? throw new InvalidOperationException("HttpContext is required to parse the pagination model from the request query.");
+		return context.Request.Query;
+	}
 }

test/MR.AspNetCore.Pagination.Tests/PaginationServiceTest.cs

@@ -311,3 +311,17 @@ public async Task KeysetPaginateAsync()
 		}
 	}
 }
+
+public class PaginationServiceQuickTest
+{
+	[Fact]
+	public void DoesNotThrowInCtorForNoHttpContext()
+	{
+		var services = new ServiceCollection();
+		services.AddTransient<PaginationService>();
+		services.Configure<PaginationOptions>(o => { });
+		var provider = services.BuildServiceProvider();
+
+		var _ = provider.GetRequiredService<PaginationService>();
+	}
+}