Connect BackgroundFetch to the OfflineItemCollection

content/browser/background_fetch/background_fetch_registration_id.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_registration_id.h"
 
+#include <iterator>
+#include <sstream>
+
+#include "base/strings/string_number_conversions.h"
+#include "base/strings/string_split.h"
+#include "base/strings/stringprintf.h"
 #include "content/common/service_worker/service_worker_types.h"
 
 namespace content {
 
+namespace {
+
+const int kSerializationVersion = 0;
+const char kSeparator = '#';
+
+}  // namespace
+
 BackgroundFetchRegistrationId::BackgroundFetchRegistrationId()
     : service_worker_registration_id_(kInvalidServiceWorkerRegistrationId) {}
 
 BackgroundFetchRegistrationId::BackgroundFetchRegistrationId(
     int64_t service_worker_registration_id,
     const url::Origin& origin,
     const std::string& tag)
     : service_worker_registration_id_(service_worker_registration_id),
       origin_(origin),
       tag_(tag) {}
 
 BackgroundFetchRegistrationId::BackgroundFetchRegistrationId(
     const BackgroundFetchRegistrationId& other) = default;
 
 BackgroundFetchRegistrationId::BackgroundFetchRegistrationId(
     BackgroundFetchRegistrationId&& other) = default;
 
 BackgroundFetchRegistrationId::~BackgroundFetchRegistrationId() = default;
 
+// Serialization format is:
+// version#service_worker_registration_id#origin#tag
+std::string BackgroundFetchRegistrationId::Serialize() const {
+  return base::StringPrintf("%d%c%ld%c%s%c%s", kSerializationVersion,
+                            kSeparator, service_worker_registration_id_,
+                            kSeparator, origin_.Serialize().c_str(), kSeparator,
+                            tag_.c_str());
+}
+
+// static
+bool BackgroundFetchRegistrationId::Deserialize(
+    const std::string& serialized_registration_id,
+    BackgroundFetchRegistrationId* out_registration_id) {
+  DCHECK(out_registration_id);
+  std::vector<std::string> parts =
+      base::SplitString(serialized_registration_id, std::string(1, kSeparator),
+                        base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL);
+  if (parts.size() <= 3)
+    return false;
+
+  // Currently, only a single version is supported.
+  int serialization_version;
+  if ((!base::StringToInt(parts[0], &serialization_version)) ||
+      (kSerializationVersion != serialization_version))
+    return false;
+
+  if (!base::StringToInt64(
+          parts[1], &out_registration_id->service_worker_registration_id_)) {
+    return false;
+  }
+
+  out_registration_id->origin_ = url::Origin(GURL(parts[2]));
+  if (out_registration_id->origin_.unique())
+    return false;
+
+  // The tag could have sparators in it, so it is possible for the SplitString
+  // to end up with more than 4 pieces. If so, concatenate all the extra pieces
+  // into a single tag.
+  if (parts.size() == 4) {
+    if (parts[3] == "")
+      return false;
+    out_registration_id->tag_ = parts[3];
+  } else {
+    std::ostringstream tag;
+    std::copy(parts.begin() + 3, parts.end() - 1,
+              std::ostream_iterator<std::string>(tag, &kSeparator));
+    tag << *(parts.end() - 1);
+    out_registration_id->tag_ = tag.str();
+  }

[Peter Beverloo, 2017/03/31 11:54:06]

What I'd love is for this branch to go away. Can we figure out a way to simplify
this? What about the following for lines 78 onward?

std::ostringstream tag;
tag << parts[3];

// It's valid for a tag to contain the |kSeparator|, so concatenate further
// parts, if any, with the |tag|. This should be a rare case.
for (size_t i = 3; i < parts.size(); ++i)
  tag << kSeparator << parts[i];

out_registration_id->tag_ = tag.str();

// The tag must be a non-empty string.
return !out_registration_id->tag_.empty();

[harkness, 2017/04/03 12:47:22]

Done.

+
+  return true;
+}
+
 BackgroundFetchRegistrationId& BackgroundFetchRegistrationId::operator=(
     const BackgroundFetchRegistrationId& other) = default;
 
 bool BackgroundFetchRegistrationId::operator==(
     const BackgroundFetchRegistrationId& other) const {
   return other.service_worker_registration_id_ ==
              service_worker_registration_id_ &&
          other.origin_ == origin_ && other.tag_ == tag_;
 }
 
 bool BackgroundFetchRegistrationId::operator!=(
     const BackgroundFetchRegistrationId& other) const {
   return !(*this == other);
 }
 
 bool BackgroundFetchRegistrationId::operator<(
     const BackgroundFetchRegistrationId& other) const {
   return service_worker_registration_id_ <
              other.service_worker_registration_id_ ||
          origin_ < other.origin_ || tag_ < other.tag_;
 }
 
 bool BackgroundFetchRegistrationId::is_null() const {
   return service_worker_registration_id_ == kInvalidServiceWorkerRegistrationId;
 }
 
 }  // namespace content