[Background Fetch] Extract Request body blobs.

This is the first step in supporting uploads for Background Fetch

Bug: 774054
Change-Id: I13188181573fcd8464df0729a09190a42b5bd2d0
Reviewed-on: https://chromium-review.googlesource.com/1160848Reviewed-by: Peter Beverloo <peter@chromium.org>
Commit-Queue: Rayan Kanso <rayankans@chromium.org>
Cr-Commit-Position: refs/heads/master@{#581349}

third_party/blink/renderer/modules/background_fetch/background_fetch_manager.cc

@@ -4,11 +4,14 @@
 
 #include "third_party/blink/renderer/modules/background_fetch/background_fetch_manager.h"
 
+#include "base/memory/scoped_refptr.h"
 #include "third_party/blink/public/platform/modules/service_worker/web_service_worker_request.h"
 #include "third_party/blink/renderer/bindings/core/v8/request_or_usv_string.h"
 #include "third_party/blink/renderer/bindings/core/v8/script_promise_resolver.h"
 #include "third_party/blink/renderer/bindings/modules/v8/request_or_usv_string_or_request_or_usv_string_sequence.h"
 #include "third_party/blink/renderer/core/dom/dom_exception.h"
+#include "third_party/blink/renderer/core/fetch/body.h"
+#include "third_party/blink/renderer/core/fetch/body_stream_buffer.h"
 #include "third_party/blink/renderer/core/fetch/request.h"
 #include "third_party/blink/renderer/core/frame/csp/content_security_policy.h"
 #include "third_party/blink/renderer/core/frame/deprecation.h"
@@ -22,6 +25,7 @@
 #include "third_party/blink/renderer/modules/service_worker/service_worker_registration.h"
 #include "third_party/blink/renderer/platform/bindings/script_state.h"
 #include "third_party/blink/renderer/platform/bindings/v8_throw_exception.h"
+#include "third_party/blink/renderer/platform/blob/blob_data.h"
 #include "third_party/blink/renderer/platform/loader/cors/cors.h"
 #include "third_party/blink/renderer/platform/loader/fetch/fetch_utils.h"
 #include "third_party/blink/renderer/platform/network/network_utils.h"
@@ -156,6 +160,31 @@ bool ShouldBlockCORSPreflight(ExecutionContext* execution_context,
   return false;
 }
 
+scoped_refptr<BlobDataHandle> ExtractBlobHandle(
+    Request* request,
+    ExceptionState& exception_state) {
+  DCHECK(request);
+
+  if (request->IsBodyLocked(exception_state) == Body::BodyLocked::kLocked ||
+      request->IsBodyUsed(exception_state) == Body::BodyUsed::kUsed) {
+    DCHECK(!exception_state.HadException());
+    exception_state.ThrowTypeError("Request body is already used");
+    return nullptr;
+  }
+
+  BodyStreamBuffer* buffer = request->BodyBuffer();
+  if (!buffer)
+    return nullptr;
+
+  auto blob_handle = buffer->DrainAsBlobDataHandle(
+      BytesConsumer::BlobSizePolicy::kDisallowBlobWithInvalidSize,
+      exception_state);
+  if (exception_state.HadException())
+    return nullptr;
+
+  return blob_handle;
+}
+
 }  // namespace
 
 BackgroundFetchManager::BackgroundFetchManager(
@@ -383,11 +412,15 @@ Vector<WebServiceWorkerRequest> BackgroundFetchManager::CreateWebRequestVector(
 
       DCHECK(request);
       request->PopulateWebServiceWorkerRequest(web_requests[i]);
+      web_requests[i].SetBlobDataHandle(
+          ExtractBlobHandle(request, exception_state));
     }
   } else if (requests.IsRequest()) {
     DCHECK(requests.GetAsRequest());
     web_requests.resize(1);
     requests.GetAsRequest()->PopulateWebServiceWorkerRequest(web_requests[0]);
+    web_requests[0].SetBlobDataHandle(
+        ExtractBlobHandle(requests.GetAsRequest(), exception_state));
   } else if (requests.IsUSVString()) {
     Request* request = Request::Create(script_state, requests.GetAsUSVString(),
                                        exception_state);

third_party/blink/renderer/modules/background_fetch/background_fetch_manager_test.cc

@@ -14,6 +14,7 @@
 #include "third_party/blink/renderer/core/fetch/request_init.h"
 #include "third_party/blink/renderer/platform/bindings/exception_state.h"
 #include "third_party/blink/renderer/platform/bindings/script_state.h"
+#include "third_party/blink/renderer/platform/blob/blob_data.h"
 
 namespace blink {
 
@@ -175,4 +176,48 @@ TEST_F(BackgroundFetchManagerTest, SequenceWithNullValue) {
             ESErrorType::kTypeError);
 }
 
+TEST_F(BackgroundFetchManagerTest, BlobsExtracted) {
+  V8TestingScope scope;
+
+  KURL image_url("https://www.example.com/my_image.png");
+  KURL icon_url("https://www.example.com/my_icon.jpg");
+
+  // Create first request with a body.
+  String body_text = "cat_pic";
+  RequestInit request_init;
+  request_init.setMethod("POST");
+  request_init.setBody(blink::ScriptValue(
+      scope.GetScriptState(), ToV8(body_text, scope.GetScriptState())));
+  Request* image_request =
+      Request::Create(scope.GetScriptState(), image_url.GetString(),
+                      request_init, scope.GetExceptionState());
+  ASSERT_FALSE(scope.GetExceptionState().HadException());
+  ASSERT_TRUE(image_request);
+  ASSERT_TRUE(image_request->HasBody());
+
+  // Create second request without a body.
+  RequestOrUSVString icon_request =
+      RequestOrUSVString::FromUSVString(icon_url.GetString());
+
+  // Create a request sequence with both requests.
+  HeapVector<RequestOrUSVString> request_sequence;
+  request_sequence.push_back(RequestOrUSVString::FromRequest(image_request));
+  request_sequence.push_back(icon_request);
+
+  RequestOrUSVStringOrRequestOrUSVStringSequence requests =
+      RequestOrUSVStringOrRequestOrUSVStringSequence::
+          FromRequestOrUSVStringSequence(request_sequence);
+
+  // Extract the blobs.
+  auto web_requests = CreateWebRequestVector(scope, requests);
+  ASSERT_FALSE(scope.GetExceptionState().HadException());
+
+  ASSERT_EQ(web_requests.size(), 2u);
+
+  ASSERT_TRUE(web_requests[0].GetBlobDataHandle());
+  EXPECT_EQ(web_requests[0].GetBlobDataHandle()->size(), body_text.length());
+
+  EXPECT_FALSE(web_requests[1].GetBlobDataHandle());
+}
+
 }  // namespace blink