partial class HttpClient
{
    public Task<byte[]> GetByteArrayAsync(string requestUri, CancellationToken cancellationToken);
    public Task<byte[]> GetByteArrayAsync(Uri requestUri, CancellationToken cancellationToken);

    public Task<Stream> GetStreamAsync(string requestUri, CancellationToken cancellationToken);
    public Task<Stream> GetStreamAsync(Uri requestUri, CancellationToken cancellationToken);

    public Task<string> GetStringAsync(string requestUri, CancellationToken cancellationToken);
    public Task<string> GetStringAsync(Uri requestUri, CancellationToken cancellationToken);
}

partial class HttpContent
{
    public Task<byte[]> ReadAsByteArrayAsync(CancellationToken cancellationToken);
    public Task<Stream> ReadAsStreamAsync(CancellationToken cancellationToken);
    public Task<string> ReadAsStringAsync(CancellationToken cancellationToken);

    protected virtual Task<Stream> CreateContentReadStreamAsync(CancellationToken cancellationToken);

    protected virtual Task SerializeToStreamAsync(Stream stream, TransportContext context, CancellationToken cancellationToken);

    public Task CopyToAsync(Stream stream, CancellationToken cancellationToken);
    public Task CopyToAsync(Stream stream, TransportContext context, CancellationToken cancellationToken);
}