Lambda Test Tool: LambdaAnnotations | Proper use of HttpResults and [FromBody] attribute.

^{Originally posted by **sergio-asenjo** August 20, 2023}
Hello!

I've been trying to figure out how to properly use HttpResults returning statement in the "Mock Lambda Test Tool".

As a short example, I've tried this:

```C#
[LambdaFunction()]
[HttpApi(LambdaHttpMethod.Get, "/")]
public IHttpResult Test(ILambdaContext context)
{
return HttpResults.Ok("Ok");
}
```

Doing so, and returning any type of HttpResults, from the UI of Mock Lambda Test Tool I'm getting a base64 return in response. As for this case, I'm getting:

`"eyJzdGF0dXNDb2RlIjoyMDAsImhlYWRlcnMiOnsiY29udGVudC10eXBlIjoidGV4dC9wbGFpbiJ9LCJDb29raWVzIjpudWxsLCJib2R5IjoiT2siLCJpc0Jhc2U2NEVuY29kZWQiOmZhbHNlfQ=="`

Which translate to:
```json
{
"statusCode": 200,
"headers": {
"content-type": "text/plain"
},
"Cookies": null,
"body": "Ok",
"isBase64Encoded": false
}
```

That's correct overall, but for testing purposes, having to decode the base64 to see what I got it's not what I would want to do recurrently. Is this intended or am I missing something? If I deploy it, through browsers I can get instantly a decoded response.

───

A second thing is that I'm trying to use a [FromBody] attribute to get some data passed in the body, like this:

```C#
[LambdaFunction()]
[HttpApi(LambdaHttpMethod.Post, "/")]
public IHttpResult Test([FromBody] Request request, ILambdaContext context)
{
return HttpResults.Ok("Ok");
}

public class Request
{
public string Name { get; set; }
}
```

If through the UI Mock Lambda Test Tool I try to send `{ "name": "test" }`, I get a ValidationException, so it doesn't even enter the Test Function completely.
This is the response (which is also base64 encoded in the UI).

```C#
{
"statusCode": 400,
"headers": {
"Content-Type": "application/json",
"x-amzn-ErrorType": "ValidationException"
},
"cookies": null,
"body": "{\u0022message\u0022: \u00221 validation error(s) detected: Value at \u0027body\u0027 failed to satisfy constraint: Value cannot be null. (Parameter \u0027json\u0027)\u0022}",
"isBase64Encoded": false
}
```

Am I using this correctly for this case? Before trying annotations, I was using the template that comes with Powertools, there I'd just pass the type (in this case would be Request) and I wouldn't get this error.

For both cases, I'm using the base template Serverless Annotation, and deleted what's inside the main Class, everything else is untouched.