Dispatch a bare Service Worker event for a finished Background Fetch

content/browser/background_fetch/background_fetch_data_manager.cc

 // Copyright 2017 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/background_fetch/background_fetch_data_manager.h"
 
+#include <algorithm>
 #include <queue>
 
 #include "base/memory/ptr_util.h"
 #include "content/browser/background_fetch/background_fetch_constants.h"
 #include "content/browser/background_fetch/background_fetch_context.h"
-#include "content/browser/background_fetch/background_fetch_job_response_data.h"
 #include "content/browser/background_fetch/background_fetch_request_info.h"
 #include "content/browser/blob_storage/chrome_blob_storage_context.h"
 #include "content/public/browser/blob_handle.h"
 #include "content/public/browser/browser_context.h"
 #include "content/public/browser/download_interrupt_reasons.h"
 #include "content/public/browser/download_item.h"
 
 namespace content {
 
 // The Registration Data class encapsulates the data stored for a particular
 // Background Fetch registration. This roughly matches the on-disk format that
 // will be adhered to in the future.
 class BackgroundFetchDataManager::RegistrationData {
  public:
   RegistrationData(const std::vector<ServiceWorkerFetchRequest>& requests,
                    const BackgroundFetchOptions& options)
       : options_(options) {
     int request_index = 0;
 
     // Convert the given |requests| to BackgroundFetchRequestInfo objects.
     for (const ServiceWorkerFetchRequest& request : requests)
-      requests_.emplace(request_index++, request);
+      pending_requests_.emplace(request_index++, request);
   }
 
   ~RegistrationData() = default;
 
   // Returns whether there are remaining requests on the request queue.
-  bool HasPendingRequests() const { return !requests_.empty(); }
+  bool HasPendingRequests() const { return !pending_requests_.empty(); }
 
   // Consumes a request from the queue that is to be fetched.
-  BackgroundFetchRequestInfo ConsumeRequest() {
-    DCHECK(!requests_.empty());
+  BackgroundFetchRequestInfo GetPendingRequest() {
+    DCHECK(!pending_requests_.empty());
 
-    BackgroundFetchRequestInfo request = requests_.front();
-    requests_.pop();
+    BackgroundFetchRequestInfo request = pending_requests_.front();
+    pending_requests_.pop();
+
+    // The |request| is considered to be active now.
+    active_requests_.push_back(request);
 
     return request;
   }
 
+  // Marks the |request| as having started with the given |download_guid|.
+  // Persistent storage needs to store the association so we can resume fetches
+  // after a browser restart, here we just verify that the |request| is active.
+  void MarkRequestAsStarted(const BackgroundFetchRequestInfo& request,
+                            const std::string& download_guid) {
+    const auto iter = std::find_if(
+        active_requests_.begin(), active_requests_.end(),
+        [&request](const BackgroundFetchRequestInfo& active_request) {
+          return active_request.request_index() == request.request_index();
+        });
+
+    // The |request| must have been consumed from this RegistrationData.
+    DCHECK(iter != active_requests_.end());
+  }
+
+  // Marks the |request| as having completed. Verifies that the |request| is
+  // currently active and moves it to the |completed_requests_| vector.
+  void MarkRequestAsComplete(const BackgroundFetchRequestInfo& request) {

[harkness, 2017/03/29 22:12:33]

Maybe add the file_path and received_bytes to this call?

[Peter Beverloo, 2017/03/29 22:20:28]

We'll need much more information, so I'd like those to be set on the |request|.
(And presumably retire |download_guid| in MarkRequestAsStarted() in favor of
that too.) That requires some more fiddling with ownership, but I'll get that
done in the near future. E2E first.

+    const auto iter = std::find_if(
+        active_requests_.begin(), active_requests_.end(),
+        [&request](const BackgroundFetchRequestInfo& active_request) {
+          return active_request.request_index() == request.request_index();
+        });
+
+    // The |request| must have been consumed from this RegistrationData.
+    DCHECK(iter != active_requests_.end());
+
+    active_requests_.erase(iter);
+    completed_requests_.push_back(request);
+  }
+
+  // Returns the vector with all completed requests part of this registration.
+  const std::vector<BackgroundFetchRequestInfo>& GetCompletedRequests() const {
+    return completed_requests_;
+  }
+
  private:
-  std::queue<BackgroundFetchRequestInfo> requests_;
   BackgroundFetchOptions options_;
 
+  // TODO(peter): BackgroundFetchRequestInfo should be stored in a
+  // unique_ptr, owned by the BackgroundFetchJobController. Right now we
+  // can't do that as we need to hold on to copies here.
+  std::queue<BackgroundFetchRequestInfo> pending_requests_;
+  std::vector<BackgroundFetchRequestInfo> active_requests_;
+
+  // TODO(peter): Right now it's safe for this to be a vector because we only
+  // allow a single parallel request. That stops when we start allowing more.
+  static_assert(kMaximumBackgroundFetchParallelRequests == 1,
+                "RegistrationData::completed_requests_ assumes no parallelism");
+
+  std::vector<BackgroundFetchRequestInfo> completed_requests_;
+
   DISALLOW_COPY_AND_ASSIGN(RegistrationData);
 };
 
 BackgroundFetchDataManager::BackgroundFetchDataManager(
     BrowserContext* browser_context)
-    : browser_context_(browser_context), weak_ptr_factory_(this) {
-  DCHECK(browser_context_);
+    : weak_ptr_factory_(this) {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+  DCHECK(browser_context);
+
+  // Store the blob storage context for the given |browser_context|.
+  blob_storage_context_ =
+      make_scoped_refptr(ChromeBlobStorageContext::GetFor(browser_context));
+  DCHECK(blob_storage_context_);
 }
 
 BackgroundFetchDataManager::~BackgroundFetchDataManager() = default;
 
 void BackgroundFetchDataManager::CreateRegistration(
     const BackgroundFetchRegistrationId& registration_id,
     const std::vector<ServiceWorkerFetchRequest>& requests,
     const BackgroundFetchOptions& options,
     CreateRegistrationCallback callback) {
   if (registrations_.find(registration_id) != registrations_.end()) {
     std::move(callback).Run(blink::mojom::BackgroundFetchError::DUPLICATED_TAG,
                             std::vector<BackgroundFetchRequestInfo>());
     return;
   }
 
   std::unique_ptr<RegistrationData> registration_data =
       base::MakeUnique<RegistrationData>(requests, options);
 
   // Create a vector with the initial requests to feed the Job Controller with.
   std::vector<BackgroundFetchRequestInfo> initial_requests;
   for (size_t i = 0; i < kMaximumBackgroundFetchParallelRequests; ++i) {
     if (!registration_data->HasPendingRequests())
       break;
 
-    initial_requests.push_back(registration_data->ConsumeRequest());
+    initial_requests.push_back(registration_data->GetPendingRequest());
   }
 
   // Store the created |registration_data| so that we can easily access it.
   registrations_.insert(
       std::make_pair(registration_id, std::move(registration_data)));
 
   // Inform the |callback| of the newly created registration.
   std::move(callback).Run(blink::mojom::BackgroundFetchError::NONE,
                           std::move(initial_requests));
 }
 
 void BackgroundFetchDataManager::MarkRequestAsStarted(
     const BackgroundFetchRegistrationId& registration_id,
     const BackgroundFetchRequestInfo& request,
     const std::string& download_guid) {
   auto iter = registrations_.find(registration_id);
   DCHECK(iter != registrations_.end());
 
-  // TODO(peter): Associate the |download_guid| with the |request|.
+  RegistrationData* registration_data = iter->second.get();
+  registration_data->MarkRequestAsStarted(request, download_guid);
 }
 
 void BackgroundFetchDataManager::MarkRequestAsCompleteAndGetNextRequest(
     const BackgroundFetchRegistrationId& registration_id,
     const BackgroundFetchRequestInfo& request,
     NextRequestCallback callback) {
   auto iter = registrations_.find(registration_id);
   DCHECK(iter != registrations_.end());
 
   RegistrationData* registration_data = iter->second.get();
-
-  // TODO(peter): Store the |request| with the |registration_data|.
+  registration_data->MarkRequestAsComplete(request);
 
   base::Optional<BackgroundFetchRequestInfo> next_request;
   if (registration_data->HasPendingRequests())
-    next_request = registration_data->ConsumeRequest();
+    next_request = registration_data->GetPendingRequest();
 
   std::move(callback).Run(next_request);
 }
 
+void BackgroundFetchDataManager::GetSettledFetchesForRegistration(
+    const BackgroundFetchRegistrationId& registration_id,
+    SettledFetchesCallback callback) {
+  auto iter = registrations_.find(registration_id);
+  DCHECK(iter != registrations_.end());
+
+  RegistrationData* registration_data = iter->second.get();
+  DCHECK(!registration_data->HasPendingRequests());
+
+  const std::vector<BackgroundFetchRequestInfo>& requests =
+      registration_data->GetCompletedRequests();
+
+  std::vector<BackgroundFetchSettledFetch> settled_fetches;
+  settled_fetches.reserve(requests.size());
+
+  std::vector<std::unique_ptr<BlobHandle>> blob_handles;
+
+  for (const auto& request : requests) {
+    BackgroundFetchSettledFetch settled_fetch;
+    settled_fetch.request = request.fetch_request();
+
+    settled_fetch.response.url_list.push_back(request.GetURL());
+    // TODO: settled_fetch.response.status_code
+    // TODO: settled_fetch.response.status_text
+    // TODO: settled_fetch.response.response_type
+    // TODO: settled_fetch.response.headers
+
+    if (request.received_bytes() > 0) {
+      DCHECK(!request.file_path().empty());
+
+      std::unique_ptr<BlobHandle> blob_handle =
+          blob_storage_context_->CreateFileBackedBlob(
+              request.file_path(), 0 /* offset */, request.received_bytes(),
+              base::Time() /* expected_modification_time */);
+
+      // TODO(peter): Appropriately handle !blob_handle
+      if (blob_handle) {
+        settled_fetch.response.blob_uuid = blob_handle->GetUUID();
+        settled_fetch.response.blob_size = request.received_bytes();
+
+        blob_handles.push_back(std::move(blob_handle));
+      }
+    }
+
+    // TODO: settled_fetch.response.error
+    // TODO: settled_fetch.response.response_time
+    // TODO: settled_fetch.response.cors_exposed_header_names
+
+    settled_fetches.push_back(settled_fetch);
+  }
+
+  std::move(callback).Run(blink::mojom::BackgroundFetchError::NONE,
+                          std::move(settled_fetches), std::move(blob_handles));
+}
+
 void BackgroundFetchDataManager::DeleteRegistration(
     const BackgroundFetchRegistrationId& registration_id,
     DeleteRegistrationCallback callback) {
   auto iter = registrations_.find(registration_id);
   if (iter == registrations_.end()) {
     std::move(callback).Run(blink::mojom::BackgroundFetchError::INVALID_TAG);
     return;
   }
 
   registrations_.erase(iter);
 
   std::move(callback).Run(blink::mojom::BackgroundFetchError::NONE);
 }
 
-void BackgroundFetchDataManager::WriteJobToStorage(
-    std::unique_ptr<BackgroundFetchJobInfo> job_info,
-    std::vector<std::unique_ptr<BackgroundFetchRequestInfo>> request_infos) {
-  // TODO(harkness): Check for job_guid clash.
-  const std::string job_guid = job_info->guid();
-  job_map_[job_guid] = std::move(job_info);
-
-  // Make an explicit copy of the original requests
-  // TODO(harkness): Replace this with actually writing to storage.
-  std::vector<BackgroundFetchRequestInfo> requests;
-  for (const auto& request_info : request_infos) {
-    requests.emplace_back(*(request_info.get()));
-  }
-  request_map_[job_guid] = std::move(requests);
-
-  // |request_infos| will be destroyed when it leaves scope here.
-}
-
-void BackgroundFetchDataManager::WriteRequestToStorage(
-    const std::string& job_guid,
-    BackgroundFetchRequestInfo* request_info) {
-  std::vector<BackgroundFetchRequestInfo>& request_infos =
-      request_map_[job_guid];
-
-  // Copy the updated |request_info| over the in-memory version.
-  for (size_t i = 0; i < request_infos.size(); i++) {
-    if (request_infos[i].guid() == request_info->guid())
-      request_infos[i] = *request_info;
-  }
-}
-
-std::unique_ptr<BackgroundFetchRequestInfo>
-BackgroundFetchDataManager::GetRequestInfo(const std::string& job_guid,
-                                           size_t request_index) {
-  // Explicitly create a copy. When this is persisted to StorageWorkerStorage,
-  // the request_map_ will not exist.
-  auto iter = request_map_.find(job_guid);
-  DCHECK(iter != request_map_.end());
-  const std::vector<BackgroundFetchRequestInfo>& request_infos = iter->second;
-
-  DCHECK(request_index <= request_infos.size());
-  return base::MakeUnique<BackgroundFetchRequestInfo>(
-      request_infos[request_index]);
-}
-
-void BackgroundFetchDataManager::GetJobResponse(
-    const std::string& job_guid,
-    const BackgroundFetchResponseCompleteCallback& callback) {
-  BrowserThread::PostTaskAndReplyWithResult(
-      BrowserThread::UI, FROM_HERE,
-      base::Bind(&ChromeBlobStorageContext::GetFor, browser_context_),
-      base::Bind(&BackgroundFetchDataManager::DidGetBlobStorageContext,
-                 weak_ptr_factory_.GetWeakPtr(), job_guid, callback));
-}
-
-void BackgroundFetchDataManager::DidGetBlobStorageContext(
-    const std::string& job_guid,
-    const BackgroundFetchResponseCompleteCallback& callback,
-    ChromeBlobStorageContext* blob_context) {
-  DCHECK(blob_context);
-  BackgroundFetchJobInfo* job_info = job_map_[job_guid].get();
-  DCHECK(job_info);
-
-  // Create a BackgroundFetchJobResponseData object which will aggregate
-  // together the response blobs.
-  job_info->set_job_response_data(
-      base::MakeUnique<BackgroundFetchJobResponseData>(job_info->num_requests(),
-                                                       callback));
-  BackgroundFetchJobResponseData* job_response_data =
-      job_info->job_response_data();
-  DCHECK(job_response_data);
-
-  // Iterate over the requests and create blobs for each response.
-  for (size_t request_index = 0; request_index < job_info->num_requests();
-       request_index++) {
-    // TODO(harkness): This will need to be asynchronous.
-    std::unique_ptr<BackgroundFetchRequestInfo> request_info =
-        GetRequestInfo(job_guid, request_index);
-
-    // TODO(harkness): Only create a blob response if the request was
-    // successful. Otherwise create an error response.
-    std::unique_ptr<BlobHandle> blob_handle =
-        blob_context->CreateFileBackedBlob(
-            request_info->file_path(), 0 /* offset */,
-            request_info->received_bytes(),
-            base::Time() /* expected_modification_time */);
-
-    job_response_data->AddResponse(*request_info.get(), std::move(blob_handle));
-  }
-}
-
-bool BackgroundFetchDataManager::UpdateRequestState(
-    const std::string& job_guid,
-    const std::string& request_guid,
-    DownloadItem::DownloadState state,
-    DownloadInterruptReason interrupt_reason) {
-  // Find the request and set the state and the interrupt reason.
-  BackgroundFetchJobInfo* job_info = job_map_[job_guid].get();
-  DCHECK(job_info);
-  BackgroundFetchRequestInfo* request =
-      job_info->GetActiveRequest(request_guid);
-  DCHECK(request);
-  request->set_state(state);
-  request->set_interrupt_reason(interrupt_reason);
-
-  // If the request is now finished, remove it from the active requests.
-  switch (state) {
-    case DownloadItem::DownloadState::COMPLETE:
-    case DownloadItem::DownloadState::CANCELLED:
-      WriteRequestToStorage(job_guid, request);
-      job_info->RemoveActiveRequest(request_guid);
-      break;
-    case DownloadItem::DownloadState::IN_PROGRESS:
-    case DownloadItem::DownloadState::INTERRUPTED:
-    case DownloadItem::DownloadState::MAX_DOWNLOAD_STATE:
-      break;
-  }
-
-  // Return a boolean indicating whether there are more requests to be
-  // processed.
-  return job_info->HasRequestsRemaining();
-}
-
-void BackgroundFetchDataManager::UpdateRequestStorageState(
-    const std::string& job_guid,
-    const std::string& request_guid,
-    const base::FilePath& file_path,
-    int64_t received_bytes) {
-  BackgroundFetchJobInfo* job_info = job_map_[job_guid].get();
-  DCHECK(job_info);
-  BackgroundFetchRequestInfo* request =
-      job_info->GetActiveRequest(request_guid);
-  DCHECK(request);
-  request->set_file_path(file_path);
-  request->set_received_bytes(received_bytes);
-}
-
-const BackgroundFetchRequestInfo&
-BackgroundFetchDataManager::GetNextBackgroundFetchRequestInfo(
-    const std::string& job_guid) {
-  BackgroundFetchJobInfo* job_info = job_map_[job_guid].get();
-  DCHECK(job_info);
-
-  // TODO(harkness): This needs to be async when it queries real storage.
-  std::unique_ptr<BackgroundFetchRequestInfo> request_info =
-      GetRequestInfo(job_guid, job_info->next_request_index());
-  const std::string request_guid = request_info->guid();
-  job_info->AddActiveRequest(std::move(request_info));
-  return *job_info->GetActiveRequest(request_guid);
-}
-
-bool BackgroundFetchDataManager::IsComplete(const std::string& job_guid) const {
-  auto iter = job_map_.find(job_guid);
-  DCHECK(iter != job_map_.end());
-  return iter->second->IsComplete();
-}
-
-bool BackgroundFetchDataManager::HasRequestsRemaining(
-    const std::string& job_guid) const {
-  auto iter = job_map_.find(job_guid);
-  DCHECK(iter != job_map_.end());
-  return iter->second->HasRequestsRemaining();
-}
-
-void BackgroundFetchDataManager::UpdateRequestDownloadGuid(
-    const std::string& job_guid,
-    const std::string& request_guid,
-    const std::string& download_guid) {
-  BackgroundFetchJobInfo* job_info = job_map_[job_guid].get();
-  DCHECK(job_info);
-  BackgroundFetchRequestInfo* request =
-      job_info->GetActiveRequest(request_guid);
-  DCHECK(request);
-  request->set_download_guid(download_guid);
-}
-
 }  // namespace content