Add a DistilledContentStore (and an in-memory impl)

components/dom_distiller/core/task_tracker.cc

Index: components/dom_distiller/core/task_tracker.cc
diff --git a/components/dom_distiller/core/task_tracker.cc b/components/dom_distiller/core/task_tracker.cc
index 5dd17d3a598b6976caabd263374948ae3f358c58..754f4fd585dd5fd5d7f36df50ee3a6ab7cd701a3 100644
--- a/components/dom_distiller/core/task_tracker.cc
+++ b/components/dom_distiller/core/task_tracker.cc
@@ -6,6 +6,7 @@
 
 #include "base/auto_reset.h"
 #include "base/message_loop/message_loop.h"
+#include "components/dom_distiller/core/distilled_content_store.h"
 #include "components/dom_distiller/core/proto/distilled_article.pb.h"
 #include "components/dom_distiller/core/proto/distilled_page.pb.h"
 
@@ -20,8 +21,11 @@ ViewerHandle::~ViewerHandle() {
   }
 }
 
-TaskTracker::TaskTracker(const ArticleEntry& entry, CancelCallback callback)
+TaskTracker::TaskTracker(const ArticleEntry& entry,
+                         CancelCallback callback,
+                         DistilledContentStore* content_store)
     : cancel_callback_(callback),
+      content_store_(content_store),
       entry_(entry),
       distilled_article_(),
       content_ready_(false),
@@ -40,7 +44,6 @@ void TaskTracker::StartDistiller(DistillerFactory* factory) {
   if (entry_.pages_size() == 0) {
     return;
   }
-
   GURL url(entry_.pages(0).url());
   DCHECK(url.is_valid());
 
@@ -53,9 +56,11 @@ void TaskTracker::StartDistiller(DistillerFactory* factory) {
 }
 
 void TaskTracker::StartBlobFetcher() {
-  // TODO(cjhopman): There needs to be some local storage for the distilled
-  // blob. When that happens, this should start some task to fetch the blob for
-  // |entry_| and asynchronously notify |this| when it is done.
+  if (content_store_) {
+    content_store_->LoadContent(entry_,
+                                base::Bind(&TaskTracker::OnBlobFetched,
+                                           weak_ptr_factory_.GetWeakPtr()));
+  }
 }
 
 void TaskTracker::AddSaveCallback(const SaveCallback& callback) {
@@ -146,11 +151,23 @@ void TaskTracker::NotifyViewer(ViewRequestDelegate* delegate) {
 
 void TaskTracker::OnDistillerFinished(
     scoped_ptr<DistilledArticleProto> distilled_article) {
-  OnDistilledArticleReady(distilled_article.Pass());
+  if (!content_ready_) {
+    OnDistilledArticleReady(distilled_article.Pass());
+  }
+}
+
+void TaskTracker::OnBlobFetched(
+    bool success,
+    scoped_ptr<DistilledArticleProto> distilled_article) {
+  if (!content_ready_ && success) {
+    OnDistilledArticleReady(distilled_article.Pass());
+  }
 }
 
 void TaskTracker::OnDistilledArticleReady(
     scoped_ptr<DistilledArticleProto> distilled_article) {
+  DCHECK(!content_ready_);
+  content_ready_ = true;
   distilled_article_ = distilled_article.Pass();
   bool distillation_successful = false;

[nyquist, 2014/04/10 19:00:13]

how about bool distillation_successful = distilled_article_->pages_size() > 0;

And then maybe even merge this and the block below?
Or have an additional if for the success if you do something along the lines of
what shashi mentioned inside the block.

[cjhopman, 2014/04/11 22:37:21]

Done.

   if (distilled_article_->pages_size() > 0) {
@@ -164,7 +181,11 @@ void TaskTracker::OnDistilledArticleReady(
     }
   }
 
-  content_ready_ = true;
+  if (distillation_successful) {

[shashi, 2014/03/18 21:14:57]

Can OnDistillerFinished determine if the distillation was successful:
(distilled_article->pages_size() > 0)  and pass that to
OnDistilledArticleReady(scoped_ptr<> distilled_article, bool success)

This was both onBlobFetched and OnDistilledFinished call OnDistilledArticleReady
with additional success parameter and only OnDistillerFinished adds the content
to the store.

[nyquist, 2014/04/10 19:00:13]

Or how about just adding a param |store_if_valid| to this method and only pass
true in OnDistillerFinished?

[cjhopman, 2014/04/11 22:37:21]

So this should be more correct now.

+    // TODO(cjhopman): If this article came from the blob fetcher, there is no
+    // reason to store it back there.
+    AddDistilledContentToStore();
+  }
 
   for (size_t i = 0; i < viewers_.size(); ++i) {
     NotifyViewer(viewers_[i]);
@@ -181,4 +202,12 @@ void TaskTracker::OnArticleDistillationUpdated(
   }
 }
 
+void TaskTracker::AddDistilledContentToStore() {
+  if (content_store_) {
+    content_store_->SaveContent(
+        entry_, *distilled_article_, DistilledContentStore::SaveCallback());
+  }
+}
+
+
 }  // namespace dom_distiller