Replaces all the foundation imports.
One issue is that `HTTPClient.init?(httpsURLWithSocketPath socketPath:
String, uri: String = "/")` uses `addingPercentEncoding()` from
Foundation. So instead, we use a pure Swift impl. that does the same.
We also need to disable default traits from `swift-configuration` to
prevent linking Foundation, because the `JSON` trait does that.
This also adds a linkage test to prevent regressions to CI.
> ## Note:
> This is a long LLM generated PR description. However it captures very
well, what has been changed and has already been reduced for brevity.
The PR is sadly quite complex but I think the description captures the
changes quite well.
This is foundational work needed to properly support HTTP trailers and
scenarios where the server sends a complete response before the client
finishes uploading (e.g., early rejection, 100-continue flows, or
bidirectional streaming protocols).
## Changes
### State Machine Improvements
- **Added `endForwarded` state** to
`Transaction.StateMachine.RequestStreamState`
- This new state distinguishes between "request data forwarded to the
channel" and "request data written to the network"
- Properly handles the race condition where response completes before
the request write completes
- **Renamed `succeedRequest` → `forwardResponseEnd`** in both
`HTTPRequestStateMachine.Action` and
`HTTP1ConnectionStateMachine.Action`
- Better reflects the semantic meaning: we're forwarding the end of the
response stream, not necessarily succeeding the entire request yet
- More accurate naming for bidirectional streaming scenarios
### Protocol Changes
- **Added `requestBodyStreamSent()` to `HTTPExecutableRequest`
protocol**
- Called by the channel handler when the request body stream has been
fully written to the network
- Allows proper coordination between request and response stream
completion
- Implemented in both `Transaction` and `RequestBag`
### Request State Machine Updates
- **Updated `FinalSuccessfulRequestAction`**
- Changed `.sendRequestEnd(EventLoopPromise<Void>?)` to simpler
`.requestDone`
- Added `.none` case for when response completes but request is still
in-flight
- Removed the need to pass promises around, simplifying the state
machine
- **`sendRequestEnd` action now includes
`FinalSuccessfulRequestAction`**
- Allows the state machine to signal what should happen after the
request completes
- Enables proper cleanup coordination (idle connection, close, or
continue)
### Channel Handler Updates
- **HTTP1ClientChannelHandler**
- `sendRequestEnd` now properly handles scenarios where response has
already completed
- Added future callback to coordinate request completion with final
actions
- Properly manages connection state (idle vs close) based on both
streams completing
- **HTTP2ClientRequestHandler**
- Updated to handle new `sendRequestEnd` signature
- Properly ignores HTTP/1-specific final actions (like `.requestDone`)
### RequestBag State Machine
- **Added `endReceived` state to `ResponseStreamState`**
- Tracks when the response has completed while request is still ongoing
- Enables proper sequencing: response end → request end → task
completion
- **Updated `FinishAction`**
- Added `.forwardStreamFinishedAndSucceedTask` for the case where both
streams complete simultaneously
- Ensures delegate methods are called in the correct order
### Error Handling
- **Improved failure handling in `Transaction.StateMachine`**
- Now properly handles errors that occur after response completes but
before request finishes
- Added `cancelExecutor` action to the fail path
- Executor is now passed to `failRequestStreamContinuation` for proper
cleanup
## Technical Details
### The Problem
Previously, when a server sent a complete response before the client
finished uploading the request body, AHC would:
1. Receive the full response (head, body, end)
2. But NOT inform the user that the response was complete if the request
was still streaming
3. Only succeed the request after both streams completed
This made it impossible to implement proper bidirectional streaming or
handle scenarios like:
- Server rejecting a large upload early (e.g., 413 Payload Too Large)
- 100-continue flows where the server responds before request completes
- HTTP trailers sent by the server
### The Solution
The new state machine properly tracks four completion states:
1. **Neither complete**: Normal request/response in flight
2. **Response complete, request ongoing**: New
`endForwarded`/`endReceived` states
3. **Request complete, response ongoing**: Existing logic
4. **Both complete**: Request succeeds
The key insight is the `endForwarded` state, which represents "we've
given all request data to the channel, but it hasn't been written to the
network yet". This allows us to:
- Immediately forward response completion to the user
- Wait for the write to complete before cleaning up resources
- Properly sequence connection state transitions
## Future Work
This PR lays the groundwork for:
- Proper internal HTTP trailer support (both sending and receiving)
---------
Co-authored-by: George Barnett <gbarnett@apple.com>
Migrate CI to use GitHub Actions.
### Motivation:
To migrate to GitHub actions and centralised infrastructure.
### Modifications:
Changes of note:
* Adopt swift-format using rules from SwiftNIO.
* Remove scripts and docker files which are no longer needed.
* Disabled warnings-as-errors on Swift 6.0 CI pipelines for now.
### Result:
Feature parity with old CI.
Motivation
It's totally acceptable for a HTTP server to respond before a request
upload has completed. If the response is an error, we should abort the
upload (and we do), but if the response is a 2xx we should probably just
finish the upload.
In this case it turns out we'll actually hit a crash when we attempt to
deliver an empty body message. his is no good!
Once that bug was fixed it revealed another: while we'd attempted to
account for this case, we hadn't tested it, and so it turns out that
shutdown would hang. As a result, I've also cleaned that up.
Modifications
- Tolerate empty circular buffers of bytes when streaming an upload.
- Notify the connection that the task is complete when we're done.
Result
Fewer crashes and hangs.
### Motivation
Currently, we don’t consume the response body of redirect responses. Because of this requests, that receive a redirect response with response body, may hang indefinitely.
### Changes
- Consume redirect response body if less than 3kb
- Cancel redirect response if larger than 3kb
### Result
Redirect responses are consumed. Fixes#574
Motivation
The RequestBag intermediates between two different threads. This means
it can get requests that were reasonable when they were made but have
been superseded with newer information since then. These generally have
to be tolerated.
Unfortunately if we received a request to resume the request body stream
_after_ the need for that stream has been invalidated, we could hit a
crash. That's unnecessary, and we should tolerate it better.
Modifications
Tolerated receiving requests to resume body streaming in the finished
state.
Result
Fewer crashes
Fixes#576
* refactor RedirectHandler
- `redirectState` is no longer a property of `HTTPClient.Request`. RedirectHandler now stores this state directly and therefore no longer optional.
- we no longer count the number of allowed redirects down. Instead the number of redirects is dervied from `self.visited.count` and we compare it to the maxRedirect to check if we git the limit.
* `HTTPClient.Configuration.RedirectConfiguration.Configuration` is now called `HTTPClient.Configuration.RedirectConfiguration.Mode`
only two `Configuration`s left in the type name
* add redirect logger test
- Adding four new protocols:
- `HTTPExecutingRequest` a protocol representing an HTTP task that is executed on a ChannelHandler.
- `HTTPScheduledRequest` a protocol representing an HTTP task that is scheduled for execution, but in a waiting state (example: Waiting for an idle connection in the connection pool).
- `HTTPRequestExecutor` a protocol that can be used from the `HTTPExecutingRequest` abstracting away functionality that will normally be implemented by a `ChannelHandler`
- `HTTPRequestScheduler` a protocol that can be used from the `HTTPScheduledRequest` abstracting away functionality that will normally be implemented by a `ConnectionPool`
- An implementation of the `HTTPExecutingTask` and `HTTPScheduledRequest` called `RequestBag`. It implements our current API using the new protocols
Co-authored-by: George Barnett <gbarnett@apple.com>
Co-authored-by: Cory Benfield <lukasa@apple.com>
Mads Odgaard
Fabian Fett
Rick Newton-Rogers
David Nadoba
Cory Benfield