Add support for custom cancellation error (#683)

Author: dnadoba

Sources/AsyncHTTPClient/HTTPHandler.swift

@@ -688,7 +688,7 @@ extension URL{
 }
 
 protocolHTTPClientTaskDelegate{
-funccancel()
+funcfail(_ error:Error)
 }
 
 extensionHTTPClient{
@@ -780,12 +780,18 @@ extension HTTPClient{
 
  /// Cancels the request execution.
 publicfunc cancel(){
+self.fail(reason:HTTPClientError.cancelled)
+}
+
+ /// Cancels the request execution with a custom `Error`.
+ /// - Parameter reason: the error that is used to fail the promise
+publicfunc fail(reason error:Error){
 lettaskDelegate=self.lock.withLock{()->HTTPClientTaskDelegate?in
 self._isCancelled =true
 returnself._taskDelegate
 }
 
- taskDelegate?.cancel()
+ taskDelegate?.fail(error)
 }
 
 func succeed<Delegate:HTTPClientResponseDelegate>(promise:EventLoopPromise<Response>?,

Sources/AsyncHTTPClient/RequestBag.swift

@@ -394,7 +394,7 @@ final class RequestBag<Delegate: HTTPClientResponseDelegate>{
 }
 }
 
-extensionRequestBag:HTTPSchedulableRequest{
+extensionRequestBag:HTTPSchedulableRequest,HTTPClientTaskDelegate{
 vartlsConfiguration:TLSConfiguration?{
 self.request.tlsConfiguration
 }
@@ -511,9 +511,3 @@ extension RequestBag: HTTPExecutableRequest{
 }
 }
 }
-
-extensionRequestBag:HTTPClientTaskDelegate{
-func cancel(){
-self.fail(HTTPClientError.cancelled)
-}
-}

Tests/AsyncHTTPClientTests/HTTP1ClientChannelHandlerTests.swift

@@ -327,7 +327,7 @@ class HTTP1ClientChannelHandlerTests: XCTestCase{
 XCTAssertNoThrow(try embedded.writeInbound(HTTPClientResponsePart.head(responseHead)))
 
  // canceling the request
- requestBag.cancel()
+ requestBag.fail(HTTPClientError.cancelled)
 XCTAssertThrowsError(try requestBag.task.futureResult.wait()){
 XCTAssertEqual($0 as?HTTPClientError,.cancelled)
 }

Tests/AsyncHTTPClientTests/HTTP2ClientRequestHandlerTests.swift

@@ -276,7 +276,7 @@ class HTTP2ClientRequestHandlerTests: XCTestCase{
 XCTAssertNoThrow(try embedded.writeInbound(HTTPClientResponsePart.head(responseHead)))
 
  // canceling the request
- requestBag.cancel()
+ requestBag.fail(HTTPClientError.cancelled)
 XCTAssertThrowsError(try requestBag.task.futureResult.wait()){
 XCTAssertEqual($0 as?HTTPClientError,.cancelled)
 }

Tests/AsyncHTTPClientTests/HTTPClientTests+XCTest.swift

@@ -52,6 +52,7 @@ extension HTTPClientTests{
 ("testStreaming", testStreaming),
 ("testFileDownload", testFileDownload),
 ("testFileDownloadError", testFileDownloadError),
+("testFileDownloadCustomError", testFileDownloadCustomError),
 ("testRemoteClose", testRemoteClose),
 ("testReadTimeout", testReadTimeout),
 ("testConnectTimeout", testConnectTimeout),

Tests/AsyncHTTPClientTests/HTTPClientTests.swift

@@ -569,6 +569,31 @@ final class HTTPClientTests: XCTestCaseHTTPClientTestsBaseClass{
 XCTAssertEqual(0, progress.receivedBytes)
 }
 
+func testFileDownloadCustomError()throws{
+letrequest=tryRequest(url:self.defaultHTTPBinURLPrefix +"get")
+structCustomError:Equatable,Error{}
+
+tryTemporaryFileHelpers.withTemporaryFilePath{ path in
+letdelegate=tryFileDownloadDelegate(path: path, reportHead:{ task, head in
+XCTAssertEqual(head.status,.ok)
+ task.fail(reason:CustomError())
+}, reportProgress:{ _, _ in
+XCTFail("should never be called")
+})
+XCTAssertThrowsError(
+tryself.defaultClient.execute(
+ request: request,
+ delegate: delegate
+)
+.wait()
+){ error in
+XCTAssertEqualTypeAndValue(error,CustomError())
+}
+
+XCTAssertFalse(TemporaryFileHelpers.fileExists(path: path))
+}
+}
+
 func testRemoteClose(){
 XCTAssertThrowsError(tryself.defaultClient.get(url:self.defaultHTTPBinURLPrefix +"close").wait()){
 XCTAssertEqual($0 as?HTTPClientError,.remoteConnectionClosed)

Tests/AsyncHTTPClientTests/HTTPConnectionPoolTests.swift

@@ -334,7 +334,7 @@ class HTTPConnectionPoolTests: XCTestCase{
 
  pool.executeRequest(requestBag)
 XCTAssertNoThrow(try eventLoop.scheduleTask(in:.seconds(1)){}.futureResult.wait())
- requestBag.cancel()
+ requestBag.fail(HTTPClientError.cancelled)
 
 XCTAssertThrowsError(try requestBag.task.futureResult.wait()){
 XCTAssertEqual($0 as?HTTPClientError,.cancelled)

Tests/AsyncHTTPClientTests/RequestBagTests.swift

@@ -220,7 +220,7 @@ final class RequestBagTests: XCTestCase{
 XCTAssert(bag.eventLoop === embeddedEventLoop)
 
 letexecutor=MockRequestExecutor(eventLoop: embeddedEventLoop)
- bag.cancel()
+ bag.fail(HTTPClientError.cancelled)
 
  bag.willExecuteRequest(executor)
 XCTAssertTrue(executor.isCancelled,"The request bag, should call cancel immediately on the executor")
@@ -301,7 +301,7 @@ final class RequestBagTests: XCTestCase{
  bag.fail(MyError())
 XCTAssertEqual(delegate.hitDidReceiveError,1)
 
- bag.cancel()
+ bag.fail(HTTPClientError.cancelled)
 XCTAssertEqual(delegate.hitDidReceiveError,1)
 
 XCTAssertThrowsError(try bag.task.futureResult.wait()){
@@ -342,7 +342,7 @@ final class RequestBagTests: XCTestCase{
 XCTAssertEqual(delegate.hitDidSendRequestHead,1)
 XCTAssertEqual(delegate.hitDidSendRequest,1)
 
- bag.cancel()
+ bag.fail(HTTPClientError.cancelled)
 XCTAssertTrue(executor.isCancelled,"The request bag, should call cancel immediately on the executor")
 
 XCTAssertThrowsError(try bag.task.futureResult.wait()){
@@ -376,7 +376,7 @@ final class RequestBagTests: XCTestCase{
  bag.requestWasQueued(queuer)
 
 XCTAssertEqual(queuer.hitCancelCount,0)
- bag.cancel()
+ bag.fail(HTTPClientError.cancelled)
 XCTAssertEqual(queuer.hitCancelCount,1)
 
 XCTAssertThrowsError(try bag.task.futureResult.wait()){
@@ -445,9 +445,9 @@ final class RequestBagTests: XCTestCase{
 letexecutor=MockRequestExecutor(eventLoop: embeddedEventLoop)
  executor.runRequest(bag)
 
- // This simulates a race between the user cancelling the task (which invokes `RequestBag.cancel`) and the
+ // This simulates a race between the user cancelling the task (which invokes `RequestBag.fail(_:)`) and the
  // call to `resumeRequestBodyStream` (which comes from the `Channel` event loop and so may have to hop.
- bag.cancel()
+ bag.fail(HTTPClientError.cancelled)
  bag.resumeRequestBodyStream()
 
 XCTAssertEqual(executor.isCancelled,true)