[API Proposal]: make ZipArchive implement IAsyncDisposable

[madelson]

Background and motivation

Disposing of a ZipArchive writes content to the underlying Stream. It would be nice to be able to do this as an async operation.

In particular, #1560 (20 upvotes) describes how not being async in this case will throw errors when writing to a ZipArchive which is an ASP.NET Core response body stream (since those streams do not allow sync IO by default). Streaming directly into a ZipArchive is a nice way to dynamically generate large file exports (e.g. streaming from a database); it's a shame that this doesn't work out of the box without enabling sync IO.

This change would also make partial progress towards supporting #1541 (95 upvotes).

API Proposal

namespace System.IO.Compression;

public class ZipArchive : IDisposable, IAsyncDisposable
{
    public ValueTask DisposeAsync();
}

API Usage

await using ZipArchive zip = new(Response.Body, ZipArchiveMode.Create, leaveOpen: true);
// generate entries here

Alternative Designs

n/a

Risks

No response

[ghost]

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Issue Details

---

Background and motivation

Disposing of a ZipArchive writes content to the underlying Stream. It would be nice to be able to do this as an async operation.

In particular, #1560 (20 upvotes) describes how not being async in this case will throw errors when writing to a ZipArchive which is an ASP.NET Core response body stream (since those streams do not allow sync IO by default). Streaming directly into a ZipArchive is a nice way to dynamically generate large file exports (e.g. streaming from a database); it's a shame that this doesn't work out of the box without enabling sync IO.

This change would also make partial progress towards supporting #1541 (95 upvotes).

API Proposal

namespace System.IO.Compression;

public class ZipArchive : IDisposable, IAsyncDisposable
{
    public ValueTask DisposeAsync();
}

API Usage

await using ZipArchive zip = new(Response.Body, ZipArchiveMode.Create, leaveOpen: true);
// generate entries here

Alternative Designs

n/a

Risks

No response

Author:	madelson
Assignees:	-
Labels:	api-suggestion, area-System.IO.Compression, untriaged
Milestone:	-

[carlossanlop]

Duplicate of #1560