Serialization/Deserialization with different media types

[pshao25]

Given a content type/accept, we need some logic like https://github.com/Azure/autorest.csharp/issues/3056#issuecomment-1429403557 to category the content type/accept into one of Binary, Form, Json, Multipart, Text, Xml. I think this logic should be at somewhere in TCGC.

In this issue, we just discuss Binary, Json, Text when there is only one content type/accept, with body type model, bytes, primitive type.

Media type: Json, body type: model

• [x] Already perfect.

Media type: Json, body type: primitive type (string, int, double, etc)

• [x] Serialization:

Actual: RequestContentHelper.FromObject(body); Expected: payload is expected, but there is boxing operation, we will optimize at https://github.com/Azure/autorest.csharp/issues/3915

• [x] Deserialization:

Actual: response.Content.ToObjectFromJson<string>()

Media type: Json, body type: bytes

• [x] Serialization:

Actual: RequestContentHelper.FromObject(body); Expected: same as above with boxing operation

• [ ] Deserialization:

Actual: response.Content Expected: response.Content.ToObjectFromJson<BinaryData>()

Media type: Binary, body type: model

• [ ] Is this a valid case?

Media type: Binary, body type: primitive type (string, int, double, etc)

• [ ] Serialization:

Actual: RequestContentHelper.FromObject(body); Expected: BinaryData.FromString(body) (only applicable to string)

• [ ] Deserialization:

Actual: response.Content.ToObjectFromJson<string>() Expected: response.Content

Media type: Binary, body type: bytes

• [x] Serialization:

Customer issue: https://github.com/Azure/autorest.csharp/issues/3793 Actual: RequestContentHelper.FromObject(body); Expected: body

• [ ] Deserialization:

Customer issue: https://github.com/Azure/autorest.csharp/issues/3963 Actual: response.Content

Media type: Text, body type: model

• [ ] Is this a valid case?

Media type: Text, body type: primitive type (string, int, double, etc)

• [ ] Serialization:

Actual: RequestContentHelper.FromObject(body) Expected: RequestContent.Create(body)

• [ ] Deserialization:

Customer issue: https://github.com/Azure/autorest.csharp/issues/3816 Actual: response.Content.ToObjectFromJson<string>() Expected: response.Content.ToString() (only applicable to string)

Media type: Text, body type: bytes

• [ ] Serialization:

Actual: RequestContentHelper.FromObject(body) Expected: ??

• [ ] Deserialization:

Actual: response.Content Expected: ??

Multiple content types

Case 1: content types come to same media type

op oneBinaryBodyTwoContentTypes(@body body: bytes, @header contentType: "application/octet-stream" | "image/jpeg"): void;

Both of the content type "application/octet-stream" and "image/jpeg" go to the media type Byte. So the conversion of body is the same as single content type. (but a new parameter content type will be added to method)

Case 2: content types come to different media types

op oneBinaryBodyTwoContentTypes(@body body: bytes, @header contentType: "application/octet-stream" | "application/json"): void;

Solution 1:

public virtual async Task<Response> OneBinaryBodyTwoContentTypesAsync(BinaryData body, ContentType contentType, CancellationToken cancellationToken = default)
{
   Argument.AssertNotNull(body, nameof(body));

  RequestContext context = FromCancellationToken(cancellationToken);
  Response response = null;
  if (contentType == ContentType.ApplicationJson)
  {
      using RequestContent content = RequestContentHelper.FromObject(body);
      response = await OneBinaryBodyTwoContentTypesAsync(content, contentType, context).ConfigureAwait(false);
  }
  else if (contentType == ContentType.ApplicationOctetStream)
  {
      using RequestContent content = body;
      response = await OneBinaryBodyTwoContentTypesAsync(content, contentType, context).ConfigureAwait(false);
  }
  return response;
}

Solution 2:

public virtual async Task<Response> OneBinaryBodyTwoContentTypesAsync(BinaryData body, ContentType contentType, CancellationToken cancellationToken = default)
{
    Argument.AssertNotNull(body, nameof(body));

    RequestContext context = FromCancellationToken(cancellationToken);
    using RequestContent content = body.ToRequestContent(contentType);
    Response response = await OneBinaryBodyTwoContentTypesAsync(content, contentType, context).ConfigureAwait(false);
    return response;
}
public static RequestContent ToRequestContent(this BinaryData binaryData, ContentType? contentType = null)
{
    if (contentType == null || contentType == ContentType.ApplicationJson)
    {
        return RequestContentHelper.FromObject(binaryData);
    }
    else if (contentType == ContentType.ApplicationOctetStream)
    {
        return binaryData;
    }

    throw new Exception();
}

Solution 3:

public virtual async Task<Response> OneBinaryBodyTwoContentTypesAsync(BinaryData body, ContentType contentType, CancellationToken cancellationToken = default)
{
    Argument.AssertNotNull(body, nameof(body));

    RequestContext context = FromCancellationToken(cancellationToken);
    RequestContent content = null;
    if (contentType == ContentType.ApplicationJson)
    {
        content = RequestContentHelper.FromObject(body);
    }
    else if (contentType == ContentType.ApplicationOctetStream)
    {
        content = body;
    }
    using (content)
    {
        return await OneBinaryBodyTwoContentTypesAsync(content, contentType, context).ConfigureAwait(false);
    }
}

Solution 4:

public virtual async Task<Response> OneBinaryBodyTwoContentTypesAsync(BinaryData body, ContentType contentType, CancellationToken cancellationToken = default)
{
    Argument.AssertNotNull(body, nameof(body));

    RequestContext context = FromCancellationToken(cancellationToken);
    RequestContent content = null;
    try
    {
        if (contentType == ContentType.ApplicationJson)
        {
            content = RequestContentHelper.FromObject(body);
        }
        else if (contentType == ContentType.ApplicationOctetStream)
        {
            content = body;
        }

        return await OneBinaryBodyTwoContentTypesAsync(content, contentType, context).ConfigureAwait(false);
    }
    finally
    {
        content.Dispose();
    }
}

[JoshLove-msft]

How will this work once azure-sdk-for-net starts consuming the new version of BinaryData with MediaType property?

[pshao25]

How will this work once azure-sdk-for-net starts consuming the new version of BinaryData with MediaType property?

@JoshLove-msft Thank you for the information! Could you help me understand how this new property is expected to be used? What is the expected value for this property?

[chunyu3]

how to model bytes: https://github.com/microsoft/typespec/issues/2703