DNR: Split FileBackedRulesetSource into RulesetSource & FileBackedRulesetSource.

In preparation of adding support for session scoped rules (which are not
file backed), split the class FileBackedRulesetSource into two classes:
a RulesetSource base class and a FileBackedRulesetSource derived class.
Since the session scoped ruleset will not be file backed, it will use
the RulesetSource class.

BUG=1043200

Change-Id: Ia06d4b2ca956de516a542aa3dc69bc70cbe1829d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2495787
Commit-Queue: Karan Bhatia <karandeepb@chromium.org>
Reviewed-by: Kelvin Jiang <kelvinjiang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#827760}

extensions/browser/api/declarative_net_request/BUILD.gn

@@ -77,6 +77,8 @@ source_set("core") {
     "parse_info.h",
     "ruleset_install_pref.cc",
     "ruleset_install_pref.h",
+    "ruleset_source.cc",
+    "ruleset_source.h",
     "utils.cc",
     "utils.h",
   ]

extensions/browser/api/declarative_net_request/file_backed_ruleset_source.cc

@@ -398,9 +398,9 @@ FileBackedRulesetSource& FileBackedRulesetSource::operator=(
     FileBackedRulesetSource&&) = default;
 
 FileBackedRulesetSource FileBackedRulesetSource::Clone() const {
-  return FileBackedRulesetSource(json_path_, indexed_path_, id_,
-                                 rule_count_limit_, extension_id_,
-                                 enabled_by_default_);
+  return FileBackedRulesetSource(json_path_, indexed_path_, id(),
+                                 rule_count_limit(), extension_id(),
+                                 enabled_by_default());
 }
 
 IndexAndPersistJSONRulesetResult
@@ -436,7 +436,7 @@ void FileBackedRulesetSource::IndexAndPersistJSONRuleset(
 
 ParseInfo FileBackedRulesetSource::IndexAndPersistRules(
     std::vector<dnr_api::Rule> rules) const {
-  DCHECK_LE(rules.size(), rule_count_limit_);
+  DCHECK_LE(rules.size(), rule_count_limit());
   DCHECK(IsAPIAvailable());
 
   FlatRulesetIndexer indexer;
@@ -447,7 +447,7 @@ ParseInfo FileBackedRulesetSource::IndexAndPersistRules(
   std::vector<int> large_regex_rule_ids;
   {
     std::set<int> id_set;  // Ensure all ids are distinct.
-    const GURL base_url = Extension::GetBaseURLFromExtensionId(extension_id_);
+    const GURL base_url = Extension::GetBaseURLFromExtensionId(extension_id());
     for (auto& rule : rules) {
       int rule_id = rule.id;
       bool inserted = id_set.insert(rule_id).second;
@@ -509,13 +509,13 @@ ReadJSONRulesResult FileBackedRulesetSource::ReadJSONRulesUnsafe() const {
         Status::kJSONParseError, std::move(value_with_error.error_message));
   }
 
-  return ParseRulesFromJSON(id_, json_path(), *value_with_error.value,
-                            rule_count_limit_, is_dynamic_ruleset());
+  return ParseRulesFromJSON(id(), json_path(), *value_with_error.value,
+                            rule_count_limit(), is_dynamic_ruleset());
 }
 
 bool FileBackedRulesetSource::WriteRulesToJSON(
     const std::vector<dnr_api::Rule>& rules) const {
-  DCHECK_LE(rules.size(), rule_count_limit_);
+  DCHECK_LE(rules.size(), rule_count_limit());
 
   std::unique_ptr<base::Value> rules_value =
       json_schema_compiler::util::CreateValueFromArray(rules);
@@ -542,12 +542,12 @@ FileBackedRulesetSource::FileBackedRulesetSource(base::FilePath json_path,
                                                  size_t rule_count_limit,
                                                  ExtensionId extension_id,
                                                  bool enabled_by_default)
-    : json_path_(std::move(json_path)),
-      indexed_path_(std::move(indexed_path)),
-      id_(id),
-      rule_count_limit_(rule_count_limit),
-      extension_id_(std::move(extension_id)),
-      enabled_by_default_(enabled_by_default) {}
+    : RulesetSource(id,
+                    rule_count_limit,
+                    std::move(extension_id),
+                    enabled_by_default),
+      json_path_(std::move(json_path)),
+      indexed_path_(std::move(indexed_path)) {}
 
 }  // namespace declarative_net_request
 }  // namespace extensions

extensions/browser/api/declarative_net_request/file_backed_ruleset_source.h

@@ -12,10 +12,9 @@
 #include "base/callback_forward.h"
 #include "base/files/file_path.h"
 #include "base/time/time.h"
+#include "extensions/browser/api/declarative_net_request/ruleset_source.h"
 #include "extensions/common/api/declarative_net_request.h"
-#include "extensions/common/api/declarative_net_request/constants.h"
 #include "extensions/common/api/declarative_net_request/dnr_manifest_data.h"
-#include "extensions/common/extension_id.h"
 
 namespace content {
 class BrowserContext;
@@ -135,8 +134,8 @@ struct ReadJSONRulesResult {
   DISALLOW_COPY_AND_ASSIGN(ReadJSONRulesResult);
 };
 
-// Holds paths for an extension ruleset.
-class FileBackedRulesetSource {
+// A Ruleset source which is backed on disk.
+class FileBackedRulesetSource : public RulesetSource {
  public:
   // Creates FileBackedRulesetSources corresponding to the static rulesets in
   // the extension package.
@@ -162,7 +161,7 @@ class FileBackedRulesetSource {
       size_t rule_count_limit,
       ExtensionId extension_id);
 
-  ~FileBackedRulesetSource();
+  ~FileBackedRulesetSource() override;
   FileBackedRulesetSource(FileBackedRulesetSource&&);
   FileBackedRulesetSource& operator=(FileBackedRulesetSource&&);
 
@@ -174,20 +173,7 @@ class FileBackedRulesetSource {
   // Path to the indexed flatbuffer rules.
   const base::FilePath& indexed_path() const { return indexed_path_; }
 
-  // Each ruleset source within an extension has a distinct ID.
-  RulesetID id() const { return id_; }
-
-  bool is_dynamic_ruleset() const { return id_ == kDynamicRulesetID; }
-
-  // The maximum number of rules that will be indexed from this source.
-  size_t rule_count_limit() const { return rule_count_limit_; }
-
-  // The ID of the extension from which the ruleset originates from.
-  const ExtensionId& extension_id() const { return extension_id_; }
-
-  // Whether the ruleset is enabled by default (as specified in the extension
-  // manifest for a static ruleset). Always true for a dynamic ruleset.
-  bool enabled_by_default() const { return enabled_by_default_; }
+  bool is_dynamic_ruleset() const { return id() == kDynamicRulesetID; }
 
   // Indexes and persists the JSON ruleset. This is potentially unsafe since the
   // JSON rules file is parsed in-process. Note: This must be called on a
@@ -228,12 +214,6 @@ class FileBackedRulesetSource {
 
   base::FilePath json_path_;
   base::FilePath indexed_path_;
-  RulesetID id_;
-  size_t rule_count_limit_;
-  ExtensionId extension_id_;
-  bool enabled_by_default_;
-
-  DISALLOW_COPY_AND_ASSIGN(FileBackedRulesetSource);
 };
 
 }  // namespace declarative_net_request

extensions/browser/api/declarative_net_request/ruleset_source.cc

+// Copyright 2020 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 "extensions/browser/api/declarative_net_request/ruleset_source.h"
+
+namespace extensions {
+namespace declarative_net_request {
+
+RulesetSource::RulesetSource(RulesetID id,
+                             size_t rule_count_limit,
+                             ExtensionId extension_id,
+                             bool enabled)
+    : id_(id),
+      rule_count_limit_(rule_count_limit),
+      extension_id_(std::move(extension_id)),
+      enabled_by_default_(enabled) {}
+
+RulesetSource::~RulesetSource() = default;
+RulesetSource::RulesetSource(RulesetSource&&) = default;
+RulesetSource& RulesetSource::operator=(RulesetSource&&) = default;
+
+}  // namespace declarative_net_request
+}  // namespace extensions

extensions/browser/api/declarative_net_request/ruleset_source.h

+// Copyright 2020 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.
+
+#ifndef EXTENSIONS_BROWSER_API_DECLARATIVE_NET_REQUEST_RULESET_SOURCE_H_
+#define EXTENSIONS_BROWSER_API_DECLARATIVE_NET_REQUEST_RULESET_SOURCE_H_
+
+#include "extensions/common/api/declarative_net_request/constants.h"
+#include "extensions/common/extension_id.h"
+
+namespace extensions {
+namespace declarative_net_request {
+
+// Encapsulates information for a single extension ruleset.
+class RulesetSource {
+ public:
+  RulesetSource(RulesetID id,
+                size_t rule_count_limit,
+                ExtensionId extension_id,
+                bool enabled);
+  virtual ~RulesetSource();
+  RulesetSource(RulesetSource&&);
+  RulesetSource& operator=(RulesetSource&&);
+  RulesetSource(const RulesetSource&) = delete;
+  RulesetSource& operator=(const RulesetSource&) = delete;
+
+  // Each ruleset source within an extension has a distinct ID.
+  RulesetID id() const { return id_; }
+
+  // The maximum number of rules that will be indexed from this source.
+  size_t rule_count_limit() const { return rule_count_limit_; }
+
+  // The ID of the extension from which the ruleset originates from.
+  const ExtensionId& extension_id() const { return extension_id_; }
+
+  // Whether the ruleset is enabled by default (as specified in the extension
+  // manifest for a static ruleset). Always true for a dynamic ruleset.
+  bool enabled_by_default() const { return enabled_by_default_; }
+
+ private:
+  RulesetID id_;
+  size_t rule_count_limit_;
+  ExtensionId extension_id_;
+  bool enabled_by_default_;
+};
+
+}  // namespace declarative_net_request
+}  // namespace extensions
+
+#endif  // EXTENSIONS_BROWSER_API_DECLARATIVE_NET_REQUEST_RULESET_SOURCE_H_