ashishdhingra
commented
1 year ago Reproducible using below code in test tool (code is ported to Lambda project type for easy debugging): .csproj
<Project Sdk="Microsoft.NET.Sdk">
<PropertyGroup>
<TargetFramework>net6.0</TargetFramework>
<ImplicitUsings>enable</ImplicitUsings>
<Nullable>enable</Nullable>
<GenerateRuntimeConfigurationFiles>true</GenerateRuntimeConfigurationFiles>
<AWSProjectType>Lambda</AWSProjectType>
<!-- This property makes the build directory similar to a publish directory and helps the AWS .NET Lambda Mock Test Tool find project dependencies. -->
<CopyLocalLockFileAssemblies>true</CopyLocalLockFileAssemblies>
<!-- Generate ready to run images during publishing to improve cold start time. -->
<PublishReadyToRun>true</PublishReadyToRun>
</PropertyGroup>
<ItemGroup>
<PackageReference Include="Amazon.Lambda.Core" Version="2.1.0" />
<PackageReference Include="Amazon.Lambda.Serialization.SystemTextJson" Version="2.3.1" />
<PackageReference Include="Amazon.Lambda.SQSEvents" Version="2.1.0" />
<PackageReference Include="JetBrains.Annotations" Version="2022.3.1" />
</ItemGroup>
</Project>Function.cs
using System.ComponentModel;
using System.Diagnostics.CodeAnalysis;
using System.Globalization;
using System.Text.Json;
using Amazon.Lambda.Core;
using Amazon.Lambda.SQSEvents;
using JetBrains.Annotations;
// Assembly attribute to enable the Lambda function's JSON input to be converted into a .NET class.
[assembly: LambdaSerializer(typeof(Amazon.Lambda.Serialization.SystemTextJson.DefaultLambdaJsonSerializer))]
namespace LambdaNet6Test;
public static class JsonOptions
{
public static readonly JsonSerializerOptions JsonSerializerOptions = new()
{
PropertyNamingPolicy = JsonNamingPolicy.CamelCase
};
}
internal class JsonTypeConverterAdapter<T> : TypeConverter
{
public override object? ConvertFrom(ITypeDescriptorContext? context, CultureInfo? culture, object value)
=> value is string stringValue
? JsonSerializer.Deserialize<T>(stringValue, JsonOptions.JsonSerializerOptions)
: base.ConvertFrom(context, culture, value);
public override object? ConvertTo(ITypeDescriptorContext? context, CultureInfo? culture, object? value,
Type destinationType)
=> value is T tValue && destinationType == typeof(string)
? JsonSerializer.Serialize(tValue)
: base.ConvertTo(context, culture, value, destinationType);
public override bool CanConvertFrom(ITypeDescriptorContext? context, Type sourceType)
=> sourceType == typeof(string) || base.CanConvertFrom(context, sourceType);
public override bool CanConvertTo(ITypeDescriptorContext? context, Type? destinationType)
=> destinationType == typeof(T) || base.CanConvertTo(context, destinationType);
}
[TypeConverter(typeof(JsonTypeConverterAdapter<S3Bucket>))]
[Serializable]
internal class S3Bucket
{
public string Bucket { get; set; } = string.Empty;
}
public class Function
{
[PublicAPI]
[SuppressMessage("Performance", "CA1822", Justification = "Lambda API")]
[SuppressMessage("Style", "IDE0060", Justification = "Lambda API")]
public string FunctionHandler(SQSEvent sqsEvent, ILambdaContext lambdaContext)
{
const string json = "{\"bucket\":\"test\"}";
var s3BucketWorks = JsonSerializer.Deserialize<S3Bucket>(json, JsonOptions.JsonSerializerOptions);
if (s3BucketWorks == null)
{
return string.Empty;
}
Console.WriteLine(s3BucketWorks.Bucket);
Console.WriteLine((s3BucketWorks.GetType() == typeof(S3Bucket)).ToString());
var s3BucketFails = TypeDescriptor.GetConverter(typeof(S3Bucket)).ConvertFrom(json);
if (s3BucketFails == null)
{
return string.Empty;
}
Console.WriteLine(s3BucketFails.GetType());
Console.WriteLine(typeof(S3Bucket));
Console.WriteLine((s3BucketFails is S3Bucket).ToString());
return string.Empty;
}
}While executing under Lambda Test tool, the statement (s3BucketFails is S3Bucket).ToString() returns False. Executing the same statement in immediate window when breakpoint is hit during debugging using Lambda Test tool returns correct value of True.
Describe the bug
When I'm running some code in the test tool, I come across an issue, when System.Text.Json.JsonSerializer.Deserialize returns different results depending on whether it's being called from the top level or from a System.ComponentModel.TypeConverter method.
This is best illustrated with code (see attachment)
lambda-test-tool.zip
Run:
Output:
This issue seems to be specific to the test tool (when I run this code in an actual Lambda, or in a console app, it works as expected).
Expected Behavior
TypeDescriptor.GetConverter(typeof T).ConvertFromandJsonSerializer.Deserialize<T>both return objects of the same typeT.Current Behavior
TypeDescriptor.GetConverter(typeof T).ConvertFromandJsonSerializer.Deserialize<T>return objects of different types.Reproduction Steps
Run:
Output:
Possible Solution
There is something weird in the way the test tool calles the framework methods. The actual lambda runtime works fine.
Additional Information/Context
No response
AWS .NET SDK and/or Package version used
Targeted .NET Platform
.NET 6
Operating System and version
Amazon Linux