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 "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) {}
@@ skipping 25 matching lines @@
     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;
 }
 
+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) {
+  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))
+    return false;
+  if (kSerializationVersion != serialization_version)
+    return false;

[Peter Beverloo, 2017/03/31 01:32:23]

nit: can combine these calls:

  int serialization_version;
  if (!base::StringToInt(parts[0], &serialization_version) ||
      serialized_version != kSerializedVersion) {
    return false;
  }

[harkness, 2017/03/31 10:11:44]

Done.

+
+  if (!base::StringToInt64(
+          parts[1], &out_registration_id.service_worker_registration_id_))
+    return false;

[Peter Beverloo, 2017/03/31 01:32:23]

{}

[harkness, 2017/03/31 10:11:44]

Done.

+
+  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. This is inefficient, but also very rare.
+  if (parts.size() == 4) {
+    if (parts[3] == "")
+      return false;
+    out_registration_id.tag_ = parts[3];
+  } else {
+    std::string tag = parts[3];
+    for (size_t i = 4; i < parts.size(); i++) {
+      tag = tag + kSeparator + parts[i];
+    }
+    out_registration_id.tag_ = tag;
+  }
+

[Peter Beverloo, 2017/03/31 01:32:23]

I wonder if you could replace this with something STL-y like:

  std::ostringstream tag;
  std::copy(parts.begin() + 3, parts.end(),
            std::ostream_iterator<std::string>(tag, kSeparator));

It's an O(n) solution so doesn't create too much overhead for the common case.

[harkness, 2017/03/31 10:11:44]

I had to tweak this a bit to make it work (not add an extra kSeparator on the
end). To me, the other code is easier to read, even if it's a bit hacky, but I
don't have a strong preference.

+  return true;
+}
+
 }  // namespace content