Bug 1666723 - Expose and add a test r=dragana,necko-reviewers

Depends on D93137

Differential Revision: https://phabricator.services.mozilla.com/D93922

netwerk/protocol/http/HttpBaseChannel.cpp

@@ -169,6 +169,7 @@ HttpBaseChannel::HttpBaseChannel()
       mTransferSize(0),
       mRequestSize(0),
       mDecodedBodySize(0),
+      mSupportsHTTP3(false),
       mEncodedBodySize(0),
       mRequestContextID(0),
       mContentWindowId(0),
@@ -1568,6 +1569,12 @@ HttpBaseChannel::GetEncodedBodySize(uint64_t* aEncodedBodySize) {
   return NS_OK;
 }
 
+NS_IMETHODIMP
+HttpBaseChannel::GetSupportsHTTP3(bool* aSupportsHTTP3) {
+  *aSupportsHTTP3 = mSupportsHTTP3;
+  return NS_OK;
+}
+
 NS_IMETHODIMP
 HttpBaseChannel::GetRequestMethod(nsACString& aMethod) {
   mRequestHead.Method(aMethod);

netwerk/protocol/http/HttpBaseChannel.h

@@ -231,6 +231,7 @@ class HttpBaseChannel : public nsHashPropertyBag,
   NS_IMETHOD GetRequestSize(uint64_t* aRequestSize) override;
   NS_IMETHOD GetDecodedBodySize(uint64_t* aDecodedBodySize) override;
   NS_IMETHOD GetEncodedBodySize(uint64_t* aEncodedBodySize) override;
+  NS_IMETHOD GetSupportsHTTP3(bool* aSupportsHTTP3) override;
   NS_IMETHOD SetRequestContextID(uint64_t aRCID) override;
   NS_IMETHOD GetIsMainDocumentChannel(bool* aValue) override;
   NS_IMETHOD SetIsMainDocumentChannel(bool aValue) override;
@@ -730,6 +731,8 @@ class HttpBaseChannel : public nsHashPropertyBag,
   uint64_t mTransferSize;
   uint64_t mRequestSize;
   uint64_t mDecodedBodySize;
+  // True only when the channel supports any of the versions of HTTP3
+  bool mSupportsHTTP3;
   uint64_t mEncodedBodySize;
   uint64_t mRequestContextID;
   // ID of the top-level document's inner window this channel is being

netwerk/protocol/http/NullHttpChannel.cpp

@@ -287,6 +287,11 @@ NullHttpChannel::GetEncodedBodySize(uint64_t* aEncodedBodySize) {
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
+NS_IMETHODIMP
+NullHttpChannel::GetSupportsHTTP3(bool* aSupportsHTTP3) {
+  return NS_ERROR_NOT_IMPLEMENTED;
+}
+
 //-----------------------------------------------------------------------------
 // NullHttpChannel::nsIChannel
 //-----------------------------------------------------------------------------

netwerk/protocol/http/nsHttpChannel.h

@@ -739,9 +739,6 @@ class nsHttpChannel final : public HttpBaseChannel,
   // is created.
   uint32_t mHTTPSSVCTelemetryReported : 1;
 
-  // True only when the channel supports any of the versions of HTTP3
-  bool mSupportsHTTP3 = false;
-
   // The origin of the top window, only valid when mTopWindowOriginComputed is
   // true.
   nsCString mTopWindowOrigin;

netwerk/protocol/http/nsIHttpChannel.idl

@@ -235,6 +235,10 @@ interface nsIHttpChannel : nsIIdentChannel
      */
     [must_use] attribute unsigned long redirectionLimit;
 
+    /**
+     * This attribute indicates if the channel has support for HTTP3
+     */
+    [must_use] readonly attribute boolean supportsHTTP3;
 
     /**************************************************************************
      * RESPONSE INFO

netwerk/protocol/viewsource/nsViewSourceChannel.cpp

@@ -223,6 +223,11 @@ nsViewSourceChannel::GetEncodedBodySize(uint64_t* aEncodedBodySize) {
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
+NS_IMETHODIMP
+nsViewSourceChannel::GetSupportsHTTP3(bool* aSupportsHTTP3) {
+  return NS_ERROR_NOT_IMPLEMENTED;
+}
+
 NS_IMETHODIMP
 nsViewSourceChannel::IsPending(bool* result) {
   NS_ENSURE_TRUE(mChannel, NS_ERROR_FAILURE);

netwerk/test/unit/test_http3.js

@@ -213,6 +213,7 @@ WaitForHttp3Listener.prototype.onStopRequest = function testOnStopRequest(
     run_next_test();
   } else {
     dump("poll later for alt svc mapping\n");
+    Assert.ok(request.supportsHTTP3);
     do_test_pending();
     do_timeout(500, () => {
       doTest(this.uri, this.expectedRoute, this.h3AltSvc);