Attempting to request from local unix socket with Swift 6.0 snapshot results in a "no such file or directory" error

[xtremekforever]

Consider the following sample code:

import AsyncHTTPClient
import Foundation

let client = HTTPClient()
defer {
    _ = client.shutdown()
}

let request = try HTTPClient.Request(
    url: URL(httpURLWithSocketPath: "/var/run/docker.sock", uri: "/_ping")!,
    method: .GET,
    headers: [
        "Host": "localhost"
    ]
)
print("Sending request: \(request)")
let response = try await client.execute(request: request).get()
print("Got response: \(response)")

When I run this with the latest Swift 6.0 snapshot (2024-08-22), it throws an error about "no such file or directory:

Sending request: Request(method: NIOHTTP1.HTTPMethod.GET, url: http+unix://%2Fvar%2Frun%2Fdocker.sock/_ping, headers: [("Host", "localhost")], body: nil, tlsConfiguration: nil, deconstructedURL: AsyncHTTPClient.DeconstructedURL(scheme: AsyncHTTPClient.Scheme.httpUnix, connectionTarget: AsyncHTTPClient.ConnectionTarget.unixSocket(path: "%2Fvar%2Frun%2Fdocker.sock"), uri: "/_ping"))
Swift/ErrorType.swift:253: Fatal error: Error raised at top level: connect(descriptor:addr:size:): No such file or directory (errno: 2)

This seems to be unique to Swift 6.0, because when I try to run the same code with a 5.10.1 toolchain, I get a successful result:

Sending request: Request(method: NIOHTTP1.HTTPMethod.GET, url: http+unix://%2Fvar%2Frun%2Fdocker.sock/_ping, headers: [("Host", "localhost")], body: nil, tlsConfiguration: nil, deconstructedURL: AsyncHTTPClient.DeconstructedURL(scheme: AsyncHTTPClient.Scheme.httpUnix, connectionTarget: AsyncHTTPClient.ConnectionTarget.unixSocket(path: "/var/run/docker.sock"), uri: "/_ping"))
Got response: Response(host: "", status: 200 OK, version: HTTP/1.1, headers: [("Api-Version", "1.47"), ("Builder-Version", "2"), ("Cache-Control", "no-cache, no-store, must-revalidate"), ("Docker-Experimental", "false"), ("Ostype", "linux"), ("Pragma", "no-cache"), ("Server", "Docker/27.2.0 (linux)"), ("Swarm", "inactive"), ("Date", "Fri, 30 Aug 2024 13:05:07 GMT"), ("Content-Length", "2"), ("Content-Type", "text/plain; charset=utf-8")], body: Optional(ByteBuffer { readerIndex: 0, writerIndex: 2, readableBytes: 2, capacity: 2, storageCapacity: 2048, slice: _ByteBufferSlice { 316..<318 }, storage: 0x00007fffec00f900 (2048 bytes) }
readable bytes (max 1k): [ 4f 4b ]))

What could possibly be causing this issue? Could it be the new Foundation that works differently with URL? I notice that the unixSocket path looks different in both instances in the log output:

6.0: AsyncHTTPClient.ConnectionTarget.unixSocket(path: "%2Fvar%2Frun%2Fdocker.sock")
5.10.1: AsyncHTTPClient.ConnectionTarget.unixSocket(path: "/var/run/docker.sock")

[xtremekforever]

Update: I found that if I change the .httpUnix/.httpsUnix deconstruction in Sources/AsyncHTTPClient/DeconstructedURL.swift to not use percent encoding it works:

        case .httpUnix, .httpsUnix:
            guard let socketPath = url.host(percentEncoded: false), !socketPath.isEmpty else {
                throw HTTPClientError.missingSocketPath
            }
            ...

So I'm going to venture that this has to do with some new default behavior in the new swift-foundation. Maybe it's an easy fix.

[FranzBusch]

This is potentially a dupe of swiftlang/swift-foundation#863. @xtremekforever Do you mind checking if you can reproduce this with latest top of tree of swift-foundation? cc @jrflat

[xtremekforever]

This is potentially a dupe of swiftlang/swift-foundation#863. @xtremekforever Do you mind checking if you can reproduce this with latest top of tree of swift-foundation? cc @jrflat

Looks like this is exactly the issue. I can try to see if I can get the latest foundation- is it as simple as including swift-foundation as a dependency in Package.swift?

[FranzBusch]

Looks like this is exactly the issue. I can try to see if I can get the latest foundation- is it as simple as including swift-foundation as a dependency in Package.swift?

Not sure if that works. I was thinking to just checkout swift-foundation and write a quick test for URL that mimics what you are doing here.

[xtremekforever]

Looks like including it in Package.swift worked. I used the following dependencies:

    dependencies: [
        .package(url: "https://github.com/swift-server/async-http-client.git", from: "1.9.0"),
        .package(url: "https://github.com/apple/swift-foundation.git", branch: "main"),
    ],

And now my example works exactly as it should without the behavior seen in this issue. Do you think this fix that's on main will be included in 6.0 eventually? It is slated for the next snapshot for example?

[FranzBusch]

@xtremekforever As far as I know yes that change should be included in the Swift 6.0 release. Thanks for confirming. Going to close this issue for now.

[jrflat]

@xtremekforever Thanks for bringing this to our attention! I'm requesting this be cherry-picked to 6.0 in swiftlang/swift-foundation#903