[API Proposal]: Add FromFile method to BinaryData

[JoshLove-msft]

Background and motivation

Oftentimes, people want to upload local files using BinaryData. In order to do this with the current API, they must write the following code:

var bd = BinaryData.FromStream(File.OpenRead("foo"));

which is not obvious to many users.
It would be better if they could simply do:

var bd = BinaryData.FromFile("foo");

API Proposal

namespace System.Memory.Data;

public partial class BinaryData
{
    public static BinaryData FromFile(string path);
    public static Task<BinaryData> FromFileAsync(string path, CancellationToken cancellationToken = default);
    public static Task<BinaryData> FromFileAsync(string path, string? mediaType, CancellationToken cancellationToken = default);
}

API Usage

var bd = BinaryData.FromFile("foo");

Alternative Designs

No response

Risks

No response

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[terrajobst]

Makes sense.

Given that FromStream also has FromStreamAsync it seems we'll want a FromFileAsync version as well:

namespace System.Memory.Data;

public partial class BinaryData
{
    public static BinaryData FromFile(string path);
    public static Task<BinaryData> FromFileAsync(string path, CancellationToken cancellationToken = default);
    public static Task<BinaryData> FromFileAsync(string path, string? mediaType, CancellationToken cancellationToken = default);
}

[skyoxZ]

namespace System.Memory.Data;

public partial class BinaryData
{
    public static BinaryData FromFile(string path);
    public static Task<BinaryData> FromFileAsync(string path);
}

Also more overloads? For mediaType and cancellationToken.

[terrajobst]

Good call. Fixed.

[dersia]

FromFile() should probably also have an overload for mediaType. and is there a need for FromFileAsJson<T>()? this would be very handy, I can also see a FromFileAsGzip() version.

[terrajobst]

FromFile() should probably also have an overload for mediaType.

I fixed that, see original comment.

And is there a need for FromFileAsJson<T>()?

Maybe? I don't recall ever having that need but that might just be me. What's the scenario for that?

I can also see a FromFileAsGzip() version

Today there is no compression handling at all in BinaryData. I think this should be a separate feature request as it seems unrelated to support files.

[terrajobst]

Video

• We should also add mediaType to the sync overload

namespace System.Memory.Data;

public partial class BinaryData
{
    public static BinaryData FromFile(string path);
    public static BinaryData FromFile(string path, string? mediaType);
    public static Task<BinaryData> FromFileAsync(string path, CancellationToken cancellationToken = default);
    public static Task<BinaryData> FromFileAsync(string path, string? mediaType, CancellationToken cancellationToken = default);
}