Consider adding Socket Send/ReceiveAsync overloads that elide SocketFlags argument

[geoffkizer]

Background and Motivation

The sync methods for Send, Receive, SendTo, and ReceiveFrom all have overloads that don't take a SocketFlags argument. This argument is rarely used.

The Task-based async methods don't have these overloads. We actually approved overloads without SocketFlags for SendTo and ReceiveFrom in #938, but these haven't been implemented yet, and it doesn't really make sense to implement them just for SendTo and ReceiveFrom.

Proposed API

Additions to existing overloads

// Existing overloads in comments
public static class SocketTaskExtensions
{
//  public static Task<int> ReceiveAsync(this Socket socket, ArraySegment<byte> buffer, SocketFlags socketFlags);
    public static Task<int> ReceiveAsync(this Socket socket, ArraySegment<byte> buffer);
    
//  public static Task<int> ReceiveAsync(this Socket socket, IList<ArraySegment<byte>> buffers, SocketFlags socketFlags);
    public static Task<int> ReceiveAsync(this Socket socket, IList<ArraySegment<byte>> buffers);
    
//  public static ValueTask<int> ReceiveAsync(this Socket socket, Memory<byte> buffer, SocketFlags socketFlags, CancellationToken cancellationToken = default(CancellationToken));
    public static ValueTask<int> ReceiveAsync(this Socket socket, Memory<byte> buffer, CancellationToken cancellationToken = default(CancellationToken));
    
//  public static Task<SocketReceiveFromResult> ReceiveFromAsync(this Socket socket, ArraySegment<byte> buffer, SocketFlags socketFlags, EndPoint remoteEndPoint);
    public static Task<SocketReceiveFromResult> ReceiveFromAsync(this Socket socket, ArraySegment<byte> buffer, EndPoint remoteEndPoint);
    
//  public static Task<SocketReceiveMessageFromResult> ReceiveMessageFromAsync(this Socket socket, ArraySegment<byte> buffer, SocketFlags socketFlags, EndPoint remoteEndPoint);
    public static Task<SocketReceiveMessageFromResult> ReceiveMessageFromAsync(this Socket socket, ArraySegment<byte> buffer, EndPoint remoteEndPoint);
    
//  public static Task<int> SendAsync(this Socket socket, ArraySegment<byte> buffer, SocketFlags socketFlags);
    public static Task<int> SendAsync(this Socket socket, ArraySegment<byte> buffer);
    
//  public static Task<int> SendAsync(this Socket socket, IList<ArraySegment<byte>> buffers, SocketFlags socketFlags);
    public static Task<int> SendAsync(this Socket socket, IList<ArraySegment<byte>> buffers);
    
//  public static ValueTask<int> SendAsync(this Socket socket, ReadOnlyMemory<byte> buffer, SocketFlags socketFlags, CancellationToken cancellationToken = default(CancellationToken));
    public static ValueTask<int> SendAsync(this Socket socket, ReadOnlyMemory<byte> buffer, CancellationToken cancellationToken = default(CancellationToken));
    
//  public static Task<int> SendToAsync(this Socket socket, ArraySegment<byte> buffer, SocketFlags socketFlags, EndPoint remoteEP);
    public static Task<int> SendToAsync(this Socket socket, ArraySegment<byte> buffer, EndPoint remoteEP);
}

Additions to #938

// #938 overloads in comments
public static class SocketTaskExtensions
{
//  public static ValueTask<int> SendToAsync(this Socket socket, ReadOnlyMemory<byte> buffer, SocketFlags socketFlags, EndPoint remoteEP, CancellationToken cancellationToken = default);
    public static ValueTask<int> SendToAsync(this Socket socket, ReadOnlyMemory<byte> buffer, EndPoint remoteEP, CancellationToken cancellationToken = default);

//  public static ValueTask<SocketReceiveFromResult> ReceiveFromAsync(this Socket socket, Memory<byte> buffer, SocketFlags socketFlags, EndPoint remoteEP, CancellationToken cancellationToken = default);
    public static ValueTask<SocketReceiveFromResult> ReceiveFromAsync(this Socket socket, Memory<byte> buffer, EndPoint remoteEP, CancellationToken cancellationToken = default);

//  public static ValueTask<SocketReceiveMessageFromResult> ReceiveMessageFromAsync(this Socket socket, Memory<byte> buffer, SocketFlags socketFlags, EndPoint remoteEP, CancellationToken cancellationToken = default);
    public static ValueTask<SocketReceiveMessageFromResult> ReceiveMessageFromAsync(this Socket socket, Memory<byte> buffer, EndPoint remoteEP, CancellationToken cancellationToken = default);
}

Consider: addition to #43933

This is not an async API but probably worth to add.

// #43933 overload in comments
public class Socket
{
//  public int ReceiveMessageFrom(Span<byte> buffer, ref SocketFlags socketFlags, ref EndPoint remoteEP, out IPPacketInformation ipPacketInformation);
    public int ReceiveMessageFrom(Span<byte> buffer, ref EndPoint remoteEP, out IPPacketInformation ipPacketInformation);
}

@scalablecory @wfurt @antonfirsov @stephentoub Thoughts?

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[antonfirsov]

This argument is rarely used.

Agreed, this will simplify call sites and improve readability. I think we should go for an API proposal. Is it just an overlook that these overloads were missing from the original proposal for SendAsync/ReceiveAsync, or was there a practical reason?

[geoffkizer]

I don't think there was a practical reason, aside from just keeping the API surface minimal.

[scalablecory]

This seems reasonable to me, especially considering we have already approved UDP APIs with these overloads.

[karelz]

Triage: Let's add them from consistency reasons.
Should be simple once the API go through API approval.

[geoffkizer]

@antonfirsov Do you want to put together the actual API proposal?

[antonfirsov]

@geoffkizer edited the opening post, hope all overloads are included.

[geoffkizer]

The new overloads for SendToAsync, ReceiveFromAsync, and ReceiveMessageFromAsync in #33418 aren't included above. I think we should include them for completeness, even though they have technically been approved already.