Do not render defaults in paging links (#827)

Author: Bart Koelman

src/JsonApiDotNetCore/Serialization/Building/LinkBuilder.cs

@@ -117,8 +117,23 @@ private string GetPageLink(ResourceContext resourceContext, int pageOffset, Page
         {
             string queryString = BuildQueryString(parameters =>
             {
-                parameters["page[size]"] = pageSize.ToString();
-                parameters["page[number]"] = pageOffset.ToString();
+                if (pageSize == null || pageSize.Equals(_options.DefaultPageSize))
+                {
+                    parameters.Remove("page[size]");
+                }
+                else
+                {
+                    parameters["page[size]"] = pageSize.ToString();
+                }
+
+                if (pageOffset == 1)
+                {
+                    parameters.Remove("page[number]");
+                }
+                else
+                {
+                    parameters["page[number]"] = pageOffset.ToString();
+                }
             });
 
             return $"{_request.BasePath}/{resourceContext.PublicName}" + queryString;

test/JsonApiDotNetCoreExampleTests/Acceptance/Spec/PaginationLinkTests.cs

@@ -56,7 +56,7 @@ public async Task When_page_number_is_specified_it_must_display_correct_top_leve
                                  "&fields[owner]=firstName&include=owner&sort=ordinal&foo=bar,baz";
             string route = pageNumber != 1
                 ? routePrefix + $"&page[size]={_defaultPageSize}&page[number]={pageNumber}"
-                : routePrefix;
+                : routePrefix + $"&page[size]={_defaultPageSize}";
 
             // Act
             var response = await _client.GetAsync(route);
@@ -67,12 +67,12 @@ public async Task When_page_number_is_specified_it_must_display_correct_top_leve
             var body = await response.Content.ReadAsStringAsync();
             var links = JsonConvert.DeserializeObject<Document>(body).Links;
 
-            Assert.EndsWith($"{routePrefix}&page[size]={_defaultPageSize}&page[number]={selfLink}", links.Self);
+            Assert.EndsWith($"{routePrefix}{GetPageNumberInQueryString(selfLink)}", links.Self);
 
             if (firstLink.HasValue)
             {
-                Assert.EndsWith($"{routePrefix}&page[size]={_defaultPageSize}&page[number]={firstLink.Value}",
-                    links.First);
+                var expected = $"{routePrefix}{GetPageNumberInQueryString(firstLink.Value)}";
+                Assert.EndsWith(expected, links.First);
             }
             else
             {
@@ -81,7 +81,8 @@ public async Task When_page_number_is_specified_it_must_display_correct_top_leve
 
             if (prevLink.HasValue)
             {
-                Assert.EndsWith($"{routePrefix}&page[size]={_defaultPageSize}&page[number]={prevLink}", links.Prev);
+                var expected = $"{routePrefix}{GetPageNumberInQueryString(prevLink.Value)}";
+                Assert.EndsWith(expected, links.Prev);
             }
             else
             {
@@ -90,7 +91,8 @@ public async Task When_page_number_is_specified_it_must_display_correct_top_leve
 
             if (nextLink.HasValue)
             {
-                Assert.EndsWith($"{routePrefix}&page[size]={_defaultPageSize}&page[number]={nextLink}", links.Next);
+                var expected = $"{routePrefix}{GetPageNumberInQueryString(nextLink.Value)}";
+                Assert.EndsWith(expected, links.Next);
             }
             else
             {
@@ -99,12 +101,18 @@ public async Task When_page_number_is_specified_it_must_display_correct_top_leve
 
             if (lastLink.HasValue)
             {
-                Assert.EndsWith($"{routePrefix}&page[size]={_defaultPageSize}&page[number]={lastLink}", links.Last);
+                var expected = $"{routePrefix}{GetPageNumberInQueryString(lastLink.Value)}";
+                Assert.EndsWith(expected, links.Last);
             }
             else
             {
                 Assert.Null(links.Last);
             }
         }
+
+        private static string GetPageNumberInQueryString(int offset)
+        {
+            return offset == 1 ? string.Empty : $"&page[number]={offset}";
+        }
     }
 }

test/UnitTests/Builders/LinkBuilderTests.cs

@@ -14,7 +14,7 @@ namespace UnitTests
 {
     public sealed class LinkBuilderTests
     {
-        private readonly IPaginationContext _paginationContext;
+        private readonly IPaginationContext _paginationContext = GetPaginationContext();
         private readonly Mock<IResourceGraph> _provider = new Mock<IResourceGraph>();
         private readonly IRequestQueryStringAccessor _queryStringAccessor = new FakeRequestQueryStringAccessor("?foo=bar");
         private const string _host = "http://www.example.com";
@@ -27,11 +27,6 @@ public sealed class LinkBuilderTests
         private const string _relSelf = "http://www.example.com/articles/123/relationships/author";
         private const string _relRelated = "http://www.example.com/articles/123/author";
 
-        public LinkBuilderTests()
-        {
-            _paginationContext = GetPaginationContext();
-        }
-
         [Theory]
         [InlineData(LinkTypes.All, LinkTypes.NotConfigured, _resourceSelf)]
         [InlineData(LinkTypes.Self, LinkTypes.NotConfigured, _resourceSelf)]
@@ -167,8 +162,8 @@ public void BuildTopLevelLinks_GlobalAndResourceConfiguration_ExpectedLinks(
                 if (pages)
                 {
                     Assert.Equal($"{_host}/articles?foo=bar&page[size]=10&page[number]=2", links.Self);
-                    Assert.Equal($"{_host}/articles?foo=bar&page[size]=10&page[number]=1", links.First);
-                    Assert.Equal($"{_host}/articles?foo=bar&page[size]=10&page[number]=1", links.Prev);
+                    Assert.Equal($"{_host}/articles?foo=bar&page[size]=10", links.First);
+                    Assert.Equal($"{_host}/articles?foo=bar&page[size]=10", links.Prev);
                     Assert.Equal($"{_host}/articles?foo=bar&page[size]=10&page[number]=3", links.Next);
                     Assert.Equal($"{_host}/articles?foo=bar&page[size]=10&page[number]=3", links.Last);
                 }
@@ -203,7 +198,7 @@ private IJsonApiOptions GetConfiguration(LinkTypes resourceLinks = LinkTypes.All
             return config.Object;
         }
 
-        private IPaginationContext GetPaginationContext()
+        private static IPaginationContext GetPaginationContext()
         {
             var mock = new Mock<IPaginationContext>();
             mock.Setup(x => x.PageNumber).Returns(new PageNumber(2));