DNR: Move shareable logic from ExtensionUrlPatternIndexMatcher to RulesetMatcherInterface.

This CL moves some logic from ExtensionUrlPatternIndexMatcher to its base class,
the RulesetMatcherInterface. In a subsequent CL, this common logic will also be
used by RegexRulesMatcher, which will evaluate regex rules.

This CL is split off of
https://chromium-review.googlesource.com/c/chromium/src/+/1892132 for ease of
review. It has no behavior change.

BUG=974391

Change-Id: I2073ed480e5f15611ce2ba4eb1ea29cf7de7f0a0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1910875
Auto-Submit: Karan Bhatia <karandeepb@chromium.org>
Reviewed-by: Istiaque Ahmed <lazyboy@chromium.org>
Commit-Queue: Karan Bhatia <karandeepb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#715131}

extensions/browser/api/declarative_net_request/BUILD.gn

@@ -32,6 +32,7 @@ source_set("declarative_net_request") {
     "ruleset_manager.h",
     "ruleset_matcher.cc",
     "ruleset_matcher.h",
+    "ruleset_matcher_interface.cc",
     "ruleset_matcher_interface.h",
     "ruleset_source.cc",
     "ruleset_source.h",

extensions/browser/api/declarative_net_request/extension_url_pattern_index_matcher.h

@@ -8,7 +8,6 @@
 #include <vector>
 
 #include "components/url_pattern_index/url_pattern_index.h"
-#include "extensions/browser/api/declarative_net_request/flat/extension_ruleset_generated.h"
 #include "extensions/browser/api/declarative_net_request/ruleset_matcher_interface.h"
 
 namespace extensions {
@@ -22,8 +21,6 @@ class ExtensionUrlPatternIndexMatcher final : public RulesetMatcherInterface {
  public:
   using UrlPatternIndexList = flatbuffers::Vector<
       flatbuffers::Offset<url_pattern_index::flat::UrlPatternIndex>>;
-  using ExtensionMetadataList =
-      flatbuffers::Vector<flatbuffers::Offset<flat::UrlRuleMetadata>>;
   ExtensionUrlPatternIndexMatcher(
       const ExtensionId& extension_id,
       api::declarative_net_request::SourceType source_type,
@@ -46,35 +43,16 @@ class ExtensionUrlPatternIndexMatcher final : public RulesetMatcherInterface {
   bool IsExtraHeadersMatcher() const override {
     return is_extra_headers_matcher_;
   }
-  const ExtensionId& extension_id() const override { return extension_id_; }
-  api::declarative_net_request::SourceType source_type() const override {
-    return source_type_;
-  }
 
  private:
   using UrlPatternIndexMatcher = url_pattern_index::UrlPatternIndexMatcher;
 
-  // Returns the ruleset's highest priority matching redirect rule and populates
-  // |redirect_url|. Returns nullptr if there is no matching redirect rule.
-  const url_pattern_index::flat::UrlRule* GetRedirectRule(
-      const RequestParams& params,
-      GURL* redirect_url) const;
-
-  // Returns the ruleset's highest priority matching upgrade scheme rule or
-  // nullptr if no matching rule is found or if the request's scheme is not
-  // upgradeable.
-  const url_pattern_index::flat::UrlRule* GetUpgradeRule(
-      const RequestParams& params) const;
-
   const url_pattern_index::flat::UrlRule* GetMatchingRule(
       const RequestParams& params,
       flat::ActionIndex index,
       UrlPatternIndexMatcher::FindRuleStrategy strategy =
           UrlPatternIndexMatcher::FindRuleStrategy::kAny) const;
 
-  const ExtensionId extension_id_;
-  const api::declarative_net_request::SourceType source_type_;
-
   const ExtensionMetadataList* const metadata_list_;
 
   // UrlPatternIndexMatchers corresponding to entries in flat::ActionIndex.

extensions/browser/api/declarative_net_request/ruleset_matcher.cc

@@ -79,6 +79,9 @@ base::Optional<RequestAction> RulesetMatcher::GetRedirectAction(
 
 base::Optional<RequestAction> RulesetMatcher::GetUpgradeAction(
     const RequestParams& params) const {
+  if (!IsUpgradeableRequest(params))
+    return base::nullopt;
+
   return url_pattern_index_matcher_.GetUpgradeAction(params);
 }
 
@@ -115,12 +118,11 @@ RulesetMatcher::RulesetMatcher(
     size_t priority,
     api::declarative_net_request::SourceType source_type,
     const ExtensionId& extension_id)
-    : ruleset_data_(std::move(ruleset_data)),
+    : RulesetMatcherInterface(extension_id, source_type),
+      ruleset_data_(std::move(ruleset_data)),
       root_(flat::GetExtensionIndexedRuleset(ruleset_data_.data())),
       id_(id),
       priority_(priority),
-      source_type_(source_type),
-      extension_id_(extension_id),
       url_pattern_index_matcher_(extension_id,
                                  source_type,
                                  root_->index_list(),

extensions/browser/api/declarative_net_request/ruleset_matcher.h

@@ -78,10 +78,6 @@ class RulesetMatcher : public RulesetMatcherInterface {
       uint8_t ignored_mask,
       std::vector<RequestAction>* remove_headers_actions) const override;
   bool IsExtraHeadersMatcher() const override;
-  const ExtensionId& extension_id() const override { return extension_id_; }
-  api::declarative_net_request::SourceType source_type() const override {
-    return source_type_;
-  }
 
   // Returns a RequestAction constructed from the matching redirect or upgrade
   // rule with the highest priority, or base::nullopt if no matching redirect or
@@ -111,11 +107,6 @@ class RulesetMatcher : public RulesetMatcherInterface {
   const size_t id_;
   const size_t priority_;
 
-  const api::declarative_net_request::SourceType source_type_;
-
-  // The ID of the extension from which this matcher's ruleset originates from.
-  const ExtensionId extension_id_;
-
   // Underlying matcher for filter-list style rules supported using the
   // |url_pattern_index| component.
   const ExtensionUrlPatternIndexMatcher url_pattern_index_matcher_;

extensions/browser/api/declarative_net_request/ruleset_matcher_interface.h

@@ -8,6 +8,7 @@
 #include <vector>
 
 #include "base/optional.h"
+#include "extensions/browser/api/declarative_net_request/flat/extension_ruleset_generated.h"
 #include "extensions/common/api/declarative_net_request.h"
 #include "extensions/common/extension_id.h"
 
@@ -17,11 +18,15 @@ namespace declarative_net_request {
 struct RequestAction;
 struct RequestParams;
 
-// An abstract interface for rule matchers. Overridden by different kinds of
+// An abstract class for rule matchers. Overridden by different kinds of
 // matchers, e.g. filter lists and regex.
+// TODO(karandeepb): This is no longer an interface. Rename this class.
 class RulesetMatcherInterface {
  public:
-  virtual ~RulesetMatcherInterface() = default;
+  RulesetMatcherInterface(const ExtensionId& extension_id,
+                          api::declarative_net_request::SourceType source_type);
+
+  virtual ~RulesetMatcherInterface();
 
   // Returns the ruleset's matching RequestAction with type |BLOCK| or
   // |COLLAPSE|, or base::nullopt if the ruleset has no matching blocking rule.
@@ -55,10 +60,50 @@ class RulesetMatcherInterface {
   virtual bool IsExtraHeadersMatcher() const = 0;
 
   // Returns the extension ID with which this matcher is associated.
-  virtual const ExtensionId& extension_id() const = 0;
+  const ExtensionId& extension_id() const { return extension_id_; }
 
   // The source type of the matcher.
-  virtual api::declarative_net_request::SourceType source_type() const = 0;
+  api::declarative_net_request::SourceType source_type() const {
+    return source_type_;
+  }
+
+ protected:
+  using ExtensionMetadataList =
+      ::flatbuffers::Vector<flatbuffers::Offset<flat::UrlRuleMetadata>>;
+
+  // Returns true if the given request can be upgraded.
+  static bool IsUpgradeableRequest(const RequestParams& params);
+
+  // Helper to create a RequestAction of type |BLOCK| or |COLLAPSE|.
+  RequestAction CreateBlockOrCollapseRequestAction(
+      const RequestParams& params,
+      const url_pattern_index::flat::UrlRule& rule) const;
+
+  // Helper to create a RequestAction of type |REDIRECT| with the request
+  // upgraded.
+  RequestAction CreateUpgradeAction(
+      const RequestParams& params,
+      const url_pattern_index::flat::UrlRule& rule) const;
+
+  // Helper to create a RequestAction of type |REDIRECT| with the appropriate
+  // redirect url. Can return base::nullopt if the redirect url is ill-formed or
+  // same as the current request url.
+  base::Optional<RequestAction> CreateRedirectAction(
+      const RequestParams& params,
+      const url_pattern_index::flat::UrlRule& rule,
+      const ExtensionMetadataList& metadata_list) const;
+
+  // Helper to create a RequestAction of type |REMOVE_HEADERS|. |mask|
+  // corresponds to bitmask of flat::RemoveHeaderType, and must be non-empty.
+  RequestAction GetRemoveHeadersActionForMask(
+      const url_pattern_index::flat::UrlRule& rule,
+      uint8_t mask) const;
+
+ private:
+  const ExtensionId extension_id_;
+  const api::declarative_net_request::SourceType source_type_;
+
+  DISALLOW_COPY_AND_ASSIGN(RulesetMatcherInterface);
 };
 
 }  // namespace declarative_net_request