Nullable reference types (#1095)

* Renamed TryXXX resource graph lookup methods to FindXXX, throwing on incoming null (not empty). Made non-public TryXXX methods tolerant against incoming nulls.

* Added directive to disable NRT in all source files

* Turn on NRT globally

* Annotated JsonApiDotNetCore library

* Use alternate public name for attribute, to improve test coverage

* Annotated example projects

* Annotated benchmark project
- Removed LinkBuilderGetNamespaceFromPathBenchmarks, we don't have such code anymore
- Cleanup query string benchmark

* Enhanced rendering of error.source.pointer on ModelState validation errors

* Respect configured MaxModelValidationErrors in operations

* Added docs for nullable reference types

* Automated cleanup code

* Fixed: do not fail when clearing a required to-many relationship

* Annotated controllers in integration tests

* Annotated DbContexts in integration tests

* Annotated fakers in integration tests

* Annotated TestBuildingBlocks

* Use Should() replacements that flow nullability

* Re-align similar testsets

* Annotated test projects, use fakers for non-trivial models in integration tests, FluentAssertions everywhere

* Fixed: make faker dates deterministic
See https://giters.com/bchavez/Bogus/issues/247

* Enable ASP.NET ModelState validation by default
Due to recent enhancements, this produces better error messages for missing required relationships and avoids 500 errors due to foreign key constraint violations.

* Check off roadmap entry

* Documented required one-to-one relationships mapping

* Added missing HEAD routes

* Prefer IDictionary<,>.TryGetValue() over .Contains() followed by indexer lookup

* Optimized response rendering time when no sparse fieldset is requested. This relies on the fact that the resource model is frozen after building the resource graph.

|                               Method |     Mean |   Error |  StdDev |
| ------------------------------------ | -------- | ------- | ------- |
| SerializeOperationsResponse (before) | 168.6 us | 1.74 us | 1.63 us |
| SerializeOperationsResponse (after)  | 148.5 us | 1.06 us | 0.99 us |
| SerializeResourceResponse   (before) | 123.7 us | 1.12 us | 1.05 us |
| SerializeResourceResponse   (after)  | 119.6 us | 1.05 us | 0.98 us |

This makes SerializeOperationsResponse 12% faster and SerializeResourceResponse 3% faster. What the benchmark does not show is the performance improvement on subsequent requests, so in practice the gain in higher.

* Fixed: handle nulls in request body

* Workaround for crash in cibuild

* Update to latest JetBrains tools

In the past, [cibuild hung after update to the latest version](#1045).
Since then, the codebase has changed and a new minor version was released. These result in the cibuild no longer hanging.

Stats from my laptop (old=v2021.1.4, new=v2021.2.2):

```
master, inspectcode (old):  2:59
master, inspectcode (new):  2:00
nrt, inspectcode (old):     3:04
nrt, inspectcode (new):     2:33

master, cleanupcode (old): 11:06
master, cleanupcode (new):  5:39
nrt, cleanupcode (old):    11:59
nrt, cleanupcode (new):     6:34
```

So the newer versions got faster. And cleanupcode still takes the most time.

In this PR, 722 of 1020 files have changed, which is 70% of the total codebase.
Because during PR cibuild, we run cleanupcode only on changed files (in chunks), this PR takes very long and sometimes times out.
This is an exceptional case, future PRs shouldn't touch so many files. So in the end, I believe this update is the best way forward.

* Package updates

* Review non-public TryXXX methods

* Addressed review feedback

Author: Bart Koelman

.config/dotnet-tools.json

@@ -3,7 +3,7 @@
   "isRoot": true,
   "tools": {
     "jetbrains.resharper.globaltools": {
-      "version": "2021.1.4",
+      "version": "2021.2.2",
       "commands": [
         "jb"
       ]

Build.ps1

@@ -8,7 +8,7 @@ function CheckLastExitCode {
 
 function RunInspectCode {
     $outputPath = [System.IO.Path]::Combine([System.IO.Path]::GetTempPath(), 'jetbrains-inspectcode-results.xml')
-    dotnet jb inspectcode JsonApiDotNetCore.sln --output="$outputPath" --profile=WarningSeverities.DotSettings --properties:Configuration=Release --severity=WARNING --verbosity=WARN -dsl=GlobalAll -dsl=SolutionPersonal -dsl=ProjectPersonal
+    dotnet jb inspectcode JsonApiDotNetCore.sln --no-build --output="$outputPath" --profile=WarningSeverities.DotSettings --properties:Configuration=Release --severity=WARNING --verbosity=WARN -dsl=GlobalAll -dsl=SolutionPersonal -dsl=ProjectPersonal
     CheckLastExitCode
 
     [xml]$xml = Get-Content "$outputPath"

CSharpGuidelinesAnalyzer.config

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
 <cSharpGuidelinesAnalyzerSettings>
   <setting rule="AV1561" name="MaxParameterCount" value="6" />
-  <setting rule="AV1561" name="MaxConstructorParameterCount" value="12" />
+  <setting rule="AV1561" name="MaxConstructorParameterCount" value="13" />
 </cSharpGuidelinesAnalyzerSettings>

Directory.Build.props

@@ -6,10 +6,11 @@
     <NpgsqlPostgreSQLVersion>5.0.*</NpgsqlPostgreSQLVersion>
     <CodeAnalysisRuleSet>$(MSBuildThisFileDirectory)CodingGuidelines.ruleset</CodeAnalysisRuleSet>
     <WarningLevel>9999</WarningLevel>
+    <Nullable>enable</Nullable>
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="JetBrains.Annotations" Version="2021.1.0" PrivateAssets="All" />
+    <PackageReference Include="JetBrains.Annotations" Version="2021.3.0" PrivateAssets="All" />
     <PackageReference Include="CSharpGuidelinesAnalyzer" Version="3.7.0" PrivateAssets="All" />
     <AdditionalFiles Include="$(MSBuildThisFileDirectory)CSharpGuidelinesAnalyzer.config" Visible="False" />
   </ItemGroup>
@@ -24,9 +25,9 @@
   <PropertyGroup>
     <BogusVersion>33.1.1</BogusVersion>
     <CoverletVersion>3.1.0</CoverletVersion>
-    <FluentAssertionsVersion>6.1.0</FluentAssertionsVersion>
+    <FluentAssertionsVersion>6.2.0</FluentAssertionsVersion>
     <MoqVersion>4.16.1</MoqVersion>
     <XUnitVersion>2.4.*</XUnitVersion>
-    <TestSdkVersion>16.11.0</TestSdkVersion>
+    <TestSdkVersion>17.0.0</TestSdkVersion>
   </PropertyGroup>
 </Project>

README.md

@@ -87,13 +87,13 @@ public class Startup
 The following chart should help you pick the best version, based on your environment.
 See also our [versioning policy](./VERSIONING_POLICY.md).
 
-| .NET version | EF Core version | JsonApiDotNetCore version |
-| ------------ | --------------- | ------------------------- |
-| Core 2.x     | 2.x             | 3.x                       |
-| Core 3.1     | 3.1             | 4.x                       |
-| Core 3.1     | 5               | 4.x                       |
-| 5            | 5               | 4.x or 5.x                |
-| 6            | 6               | 5.x                       |
+| .NET version | Entity Framework Core version | JsonApiDotNetCore version |
+| ------------ | ----------------------------- | ------------------------- |
+| Core 2.x     | 2.x                           | 3.x                       |
+| Core 3.1     | 3.1                           | 4.x                       |
+| Core 3.1     | 5                             | 4.x                       |
+| 5            | 5                             | 4.x or 5.x                |
+| 6            | 6                             | 5.x                       |
 
 ## Contributing
 

ROADMAP.md

@@ -21,7 +21,7 @@ The need for breaking changes has blocked several efforts in the v4.x release, s
 - [x] Optimized delete to-many [#1030](https://github.com/json-api-dotnet/JsonApiDotNetCore/issues/1030)
 - [x] Support System.Text.Json [#664](https://github.com/json-api-dotnet/JsonApiDotNetCore/issues/664) [#999](https://github.com/json-api-dotnet/JsonApiDotNetCore/issues/999) [1077](https://github.com/json-api-dotnet/JsonApiDotNetCore/issues/1077) [1078](https://github.com/json-api-dotnet/JsonApiDotNetCore/issues/1078)
 - [x] Optimize IIdentifiable to ResourceObject conversion [#1028](https://github.com/json-api-dotnet/JsonApiDotNetCore/issues/1028) [#1024](https://github.com/json-api-dotnet/JsonApiDotNetCore/issues/1024) [#233](https://github.com/json-api-dotnet/JsonApiDotNetCore/issues/233)
-- [ ] Nullable reference types [#1029](https://github.com/json-api-dotnet/JsonApiDotNetCore/issues/1029)
+- [x] Nullable reference types [#1029](https://github.com/json-api-dotnet/JsonApiDotNetCore/issues/1029)
 
 Aside from the list above, we have interest in the following topics. It's too soon yet to decide whether they'll make it into v5.x or in a later major version.
 

benchmarks/BenchmarkResource.cs

@@ -9,7 +9,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="BenchmarkDotNet" Version="0.13.0" />
+    <PackageReference Include="BenchmarkDotNet" Version="0.13.1" />
     <PackageReference Include="Moq" Version="$(MoqVersion)" />
   </ItemGroup>
 </Project>

benchmarks/BenchmarkResourcePublicNames.cs

@@ -21,7 +21,7 @@ public abstract class DeserializationBenchmarkBase
         protected DeserializationBenchmarkBase()
         {
             var options = new JsonApiOptions();
-            IResourceGraph resourceGraph = new ResourceGraphBuilder(options, NullLoggerFactory.Instance).Add<ResourceA>().Build();
+            IResourceGraph resourceGraph = new ResourceGraphBuilder(options, NullLoggerFactory.Instance).Add<IncomingResource>().Build();
             options.SerializerOptions.Converters.Add(new ResourceObjectConverter(resourceGraph));
             SerializerReadOptions = ((IJsonApiOptions)options).SerializerReadOptions;
 
@@ -30,7 +30,9 @@ protected DeserializationBenchmarkBase()
             var resourceDefinitionAccessor = new ResourceDefinitionAccessor(resourceGraph, serviceContainer);
 
             serviceContainer.AddService(typeof(IResourceDefinitionAccessor), resourceDefinitionAccessor);
-            serviceContainer.AddService(typeof(IResourceDefinition<ResourceA, int>), new JsonApiResourceDefinition<ResourceA, int>(resourceGraph));
+
+            serviceContainer.AddService(typeof(IResourceDefinition<IncomingResource, int>),
+                new JsonApiResourceDefinition<IncomingResource, int>(resourceGraph));
 
             // ReSharper disable once VirtualMemberCallInConstructor
             JsonApiRequest request = CreateJsonApiRequest(resourceGraph);
@@ -56,7 +58,7 @@ protected DeserializationBenchmarkBase()
         protected abstract JsonApiRequest CreateJsonApiRequest(IResourceGraph resourceGraph);
 
         [UsedImplicitly(ImplicitUseTargetFlags.Members)]
-        public sealed class ResourceA : Identifiable<int>
+        public sealed class IncomingResource : Identifiable<int>
         {
             [Attr]
             public bool Attribute01 { get; set; }
@@ -74,7 +76,7 @@ public sealed class ResourceA : Identifiable<int>
             public float? Attribute05 { get; set; }
 
             [Attr]
-            public string Attribute06 { get; set; }
+            public string Attribute06 { get; set; } = null!;
 
             [Attr]
             public DateTime? Attribute07 { get; set; }
@@ -89,34 +91,34 @@ public sealed class ResourceA : Identifiable<int>
             public DayOfWeek Attribute10 { get; set; }
 
             [HasOne]
-            public ResourceA Single1 { get; set; }
+            public IncomingResource Single1 { get; set; } = null!;
 
             [HasOne]
-            public ResourceA Single2 { get; set; }
+            public IncomingResource Single2 { get; set; } = null!;
 
             [HasOne]
-            public ResourceA Single3 { get; set; }
+            public IncomingResource Single3 { get; set; } = null!;
 
             [HasOne]
-            public ResourceA Single4 { get; set; }
+            public IncomingResource Single4 { get; set; } = null!;
 
             [HasOne]
-            public ResourceA Single5 { get; set; }
+            public IncomingResource Single5 { get; set; } = null!;
 
             [HasMany]
-            public ISet<ResourceA> Multi1 { get; set; }
+            public ISet<IncomingResource> Multi1 { get; set; } = null!;
 
             [HasMany]
-            public ISet<ResourceA> Multi2 { get; set; }
+            public ISet<IncomingResource> Multi2 { get; set; } = null!;
 
             [HasMany]
-            public ISet<ResourceA> Multi3 { get; set; }
+            public ISet<IncomingResource> Multi3 { get; set; } = null!;
 
             [HasMany]
-            public ISet<ResourceA> Multi4 { get; set; }
+            public ISet<IncomingResource> Multi4 { get; set; } = null!;
 
             [HasMany]
-            public ISet<ResourceA> Multi5 { get; set; }
+            public ISet<IncomingResource> Multi5 { get; set; } = null!;
         }
     }
 }