net/http: revert "support streaming POST content in wasm"

CL 458395 added support for streaming POST content in Wasm.
Unfortunately, this breaks requests to servers that only support HTTP/1.1.
Revert the change until a suitable fallback or opt-in strategy can be decided.

Fixes #61889

Change-Id: If53a77e1890132063b39abde867d34515d4ac2af
Reviewed-on: https://go-review.googlesource.com/c/go/+/522955
Run-TryBot: Johan Brandhorst-Satzkorn <[email protected]>
Reviewed-by: Damien Neil <[email protected]>
TryBot-Result: Gopher Robot <[email protected]>
Reviewed-by: Bryan Mills <[email protected]>
Reviewed-by: Johan Brandhorst-Satzkorn <[email protected]>

src/net/http/roundtrip_js.go

@@ -12,7 +12,6 @@ import (
 	"io"
 	"strconv"
 	"strings"
-	"sync"
 	"syscall/js"
 )
 
@@ -56,38 +55,6 @@ var jsFetchMissing = js.Global().Get("fetch").IsUndefined()
 var jsFetchDisabled = js.Global().Get("process").Type() == js.TypeObject &&
 	strings.HasPrefix(js.Global().Get("process").Get("argv0").String(), "node")
 
-// Determine whether the JS runtime supports streaming request bodies.
-// Courtesy: https://developer.chrome.com/articles/fetch-streaming-requests/#feature-detection
-var supportsPostRequestStreams = sync.OnceValue(func() bool {
-	requestOpt := js.Global().Get("Object").New()
-	requestBody := js.Global().Get("ReadableStream").New()
-
-	requestOpt.Set("method", "POST")
-	requestOpt.Set("body", requestBody)
-
-	// There is quite a dance required to define a getter if you do not have the { get property() { ... } }
-	// syntax available. However, it is possible:
-	// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/get#defining_a_getter_on_existing_objects_using_defineproperty
-	duplexCalled := false
-	duplexGetterObj := js.Global().Get("Object").New()
-	duplexGetterFunc := js.FuncOf(func(this js.Value, args []js.Value) any {
-		duplexCalled = true
-		return "half"
-	})
-	defer duplexGetterFunc.Release()
-	duplexGetterObj.Set("get", duplexGetterFunc)
-	js.Global().Get("Object").Call("defineProperty", requestOpt, "duplex", duplexGetterObj)
-
-	// Slight difference here between the aforementioned example: Non-browser-based runtimes
-	// do not have a non-empty API Base URL (https://html.spec.whatwg.org/multipage/webappapis.html#api-base-url)
-	// so we have to supply a valid URL here.
-	requestObject := js.Global().Get("Request").New("https://www.example.org", requestOpt)
-
-	hasContentTypeHeader := requestObject.Get("headers").Call("has", "Content-Type").Bool()
-
-	return duplexCalled && !hasContentTypeHeader
-})
-
 // RoundTrip implements the RoundTripper interface using the WHATWG Fetch API.
 func (t *Transport) RoundTrip(req *Request) (*Response, error) {
 	// The Transport has a documented contract that states that if the DialContext or
@@ -137,63 +104,24 @@ func (t *Transport) RoundTrip(req *Request) (*Response, error) {
 	opt.Set("headers", headers)
 
 	if req.Body != nil {
-		if !supportsPostRequestStreams() {
-			body, err := io.ReadAll(req.Body)
-			if err != nil {
-				req.Body.Close() // RoundTrip must always close the body, including on errors.
-				return nil, err
-			}
-			req.Body.Close()
-			if len(body) != 0 {
-				buf := uint8Array.New(len(body))
-				js.CopyBytesToJS(buf, body)
-				opt.Set("body", buf)
-			}
-		} else {
-			readableStreamCtorArg := js.Global().Get("Object").New()
-			readableStreamCtorArg.Set("type", "bytes")
-			readableStreamCtorArg.Set("autoAllocateChunkSize", t.writeBufferSize())
-
-			readableStreamPull := js.FuncOf(func(this js.Value, args []js.Value) any {
-				controller := args[0]
-				byobRequest := controller.Get("byobRequest")
-				if byobRequest.IsNull() {
-					controller.Call("close")
-				}
-
-				byobRequestView := byobRequest.Get("view")
-
-				bodyBuf := make([]byte, byobRequestView.Get("byteLength").Int())
-				readBytes, readErr := io.ReadFull(req.Body, bodyBuf)
-				if readBytes > 0 {
-					buf := uint8Array.New(byobRequestView.Get("buffer"))
-					js.CopyBytesToJS(buf, bodyBuf)
-					byobRequest.Call("respond", readBytes)
-				}
-
-				if readErr == io.EOF || readErr == io.ErrUnexpectedEOF {
-					controller.Call("close")
-				} else if readErr != nil {
-					readErrCauseObject := js.Global().Get("Object").New()
-					readErrCauseObject.Set("cause", readErr.Error())
-					readErr := js.Global().Get("Error").New("io.ReadFull failed while streaming POST body", readErrCauseObject)
-					controller.Call("error", readErr)
-				}
-				// Note: This a return from the pull callback of the controller and *not* RoundTrip().
-				return nil
-			})
-			defer func() {
-				readableStreamPull.Release()
-				req.Body.Close()
-			}()
-			readableStreamCtorArg.Set("pull", readableStreamPull)
-
-			opt.Set("body", js.Global().Get("ReadableStream").New(readableStreamCtorArg))
-			// There is a requirement from the WHATWG fetch standard that the duplex property of
-			// the object given as the options argument to the fetch call be set to 'half'
-			// when the body property of the same options object is a ReadableStream:
-			// https://fetch.spec.whatwg.org/#dom-requestinit-duplex
-			opt.Set("duplex", "half")
+		// TODO(johanbrandhorst): Stream request body when possible.
+		// See https://bugs.chromium.org/p/chromium/issues/detail?id=688906 for Blink issue.
+		// See https://bugzilla.mozilla.org/show_bug.cgi?id=1387483 for Firefox issue.
+		// See https://github.com/web-platform-tests/wpt/issues/7693 for WHATWG tests issue.
+		// See https://developer.mozilla.org/en-US/docs/Web/API/Streams_API for more details on the Streams API
+		// and browser support.
+		// NOTE(haruyama480): Ensure HTTP/1 fallback exists.
+		// See https://go.dev/issue/61889 for discussion.
+		body, err := io.ReadAll(req.Body)
+		if err != nil {
+			req.Body.Close() // RoundTrip must always close the body, including on errors.
+			return nil, err
+		}
+		req.Body.Close()
+		if len(body) != 0 {
+			buf := uint8Array.New(len(body))
+			js.CopyBytesToJS(buf, body)
+			opt.Set("body", buf)
 		}
 	}