Merge pull request #34208 from yskkin/inspect_with_parameter_filter

Implement AR#inspect using ParameterFilter

2 files changed, 94 insertions, 22 deletions

diff --git a/activesupport/lib/active_support/parameter_filter.rb b/activesupport/lib/active_support/parameter_filter.rb
index 59945e9daa..1389d82523 100644
--- a/activesupport/lib/active_support/parameter_filter.rb
+++ b/activesupport/lib/active_support/parameter_filter.rb
@@ -28,22 +28,36 @@ module ActiveSupport
   class ParameterFilter
     FILTERED = "[FILTERED]" # :nodoc:
 
-    def initialize(filters = [])
+    # Create instance with given filters. Supported type of filters are +String+, +Regexp+, and +Proc+.
+    # Other types of filters are treated as +String+ using +to_s+.
+    # For +Proc+ filters, key, value, and optional original hash is passed to block arguments.
+    #
+    # ==== Options
+    #
+    # * <tt>:mask</tt> - A replaced object when filtered. Defaults to +"[FILTERED]"+
+    def initialize(filters = [], mask: FILTERED)
       @filters = filters
+      @mask = mask
     end
 
+    # Mask value of +params+ if key matches one of filters.
     def filter(params)
       compiled_filter.call(params)
     end
 
+    # Returns filtered value for given key. For +Proc+ filters, third block argument is not populated.
+    def filter_param(key, value)
+      @filters.empty? ? value : compiled_filter.value_for_key(key, value)
+    end
+
   private
 
     def compiled_filter
-      @compiled_filter ||= CompiledFilter.compile(@filters)
+      @compiled_filter ||= CompiledFilter.compile(@filters, mask: @mask)
     end
 
     class CompiledFilter # :nodoc:
-      def self.compile(filters)
+      def self.compile(filters, mask:)
         return lambda { |params| params.dup } if filters.empty?
 
         strings, regexps, blocks = [], [], []
@@ -65,42 +79,46 @@ module ActiveSupport
         regexps << Regexp.new(strings.join("|"), true) unless strings.empty?
         deep_regexps << Regexp.new(deep_strings.join("|"), true) unless deep_strings.empty?
 
-        new regexps, deep_regexps, blocks
+        new regexps, deep_regexps, blocks, mask: mask
       end
 
       attr_reader :regexps, :deep_regexps, :blocks
 
-      def initialize(regexps, deep_regexps, blocks)
+      def initialize(regexps, deep_regexps, blocks, mask:)
         @regexps = regexps
         @deep_regexps = deep_regexps.any? ? deep_regexps : nil
         @blocks = blocks
+        @mask = mask
       end
 
       def call(params, parents = [], original_params = params)
         filtered_params = params.class.new
 
         params.each do |key, value|
-          parents.push(key) if deep_regexps
-          if regexps.any? { |r| key =~ r }
-            value = FILTERED
-          elsif deep_regexps && (joined = parents.join(".")) && deep_regexps.any? { |r| joined =~ r }
-            value = FILTERED
-          elsif value.is_a?(Hash)
-            value = call(value, parents, original_params)
-          elsif value.is_a?(Array)
-            value = value.map { |v| v.is_a?(Hash) ? call(v, parents, original_params) : v }
-          elsif blocks.any?
-            key = key.dup if key.duplicable?
-            value = value.dup if value.duplicable?
-            blocks.each { |b| b.arity == 2 ? b.call(key, value) : b.call(key, value, original_params) }
-          end
-          parents.pop if deep_regexps
-
-          filtered_params[key] = value
+          filtered_params[key] = value_for_key(key, value, parents, original_params)
         end
 
         filtered_params
       end
+
+      def value_for_key(key, value, parents = [], original_params = nil)
+        parents.push(key) if deep_regexps
+        if regexps.any? { |r| r.match?(key) }
+          value = @mask
+        elsif deep_regexps && (joined = parents.join(".")) && deep_regexps.any? { |r| r.match?(joined) }
+          value = @mask
+        elsif value.is_a?(Hash)
+          value = call(value, parents, original_params)
+        elsif value.is_a?(Array)
+          value = value.map { |v| v.is_a?(Hash) ? call(v, parents, original_params) : v }
+        elsif blocks.any?
+          key = key.dup if key.duplicable?
+          value = value.dup if value.duplicable?
+          blocks.each { |b| b.arity == 2 ? b.call(key, value) : b.call(key, value, original_params) }
+        end
+        parents.pop if deep_regexps
+        value
+      end
     end
   end
 end
diff --git a/activesupport/test/parameter_filter_test.rb b/activesupport/test/parameter_filter_test.rb
index 3403a3188b..d2dc71061d 100644
--- a/activesupport/test/parameter_filter_test.rb
+++ b/activesupport/test/parameter_filter_test.rb
@@ -36,6 +36,51 @@ class ParameterFilterTest < ActiveSupport::TestCase
     end
   end
 
+  test "filter should return mask option when value is filtered" do
+    mask = Object.new.freeze
+    test_hashes = [
+    [{ "foo" => "bar" }, { "foo" => "bar" }, %w'food'],
+    [{ "foo" => "bar" }, { "foo" => mask }, %w'foo'],
+    [{ "foo" => "bar", "bar" => "foo" }, { "foo" => mask, "bar" => "foo" }, %w'foo baz'],
+    [{ "foo" => "bar", "baz" => "foo" }, { "foo" => mask, "baz" => mask }, %w'foo baz'],
+    [{ "bar" => { "foo" => "bar", "bar" => "foo" } }, { "bar" => { "foo" => mask, "bar" => "foo" } }, %w'fo'],
+    [{ "foo" => { "foo" => "bar", "bar" => "foo" } }, { "foo" => mask }, %w'f banana'],
+    [{ "deep" => { "cc" => { "code" => "bar", "bar" => "foo" }, "ss" => { "code" => "bar" } } }, { "deep" => { "cc" => { "code" => mask, "bar" => "foo" }, "ss" => { "code" => "bar" } } }, %w'deep.cc.code'],
+    [{ "baz" => [{ "foo" => "baz" }, "1"] }, { "baz" => [{ "foo" => mask }, "1"] }, [/foo/]]]
+
+    test_hashes.each do |before_filter, after_filter, filter_words|
+      parameter_filter = ActiveSupport::ParameterFilter.new(filter_words, mask: mask)
+      assert_equal after_filter, parameter_filter.filter(before_filter)
+
+      filter_words << "blah"
+      filter_words << lambda { |key, value|
+        value.reverse! if key =~ /bargain/
+      }
+      filter_words << lambda { |key, value, original_params|
+        value.replace("world!") if original_params["barg"]["blah"] == "bar" && key == "hello"
+      }
+
+      parameter_filter = ActiveSupport::ParameterFilter.new(filter_words, mask: mask)
+      before_filter["barg"] = { :bargain => "gain", "blah" => "bar", "bar" => { "bargain" => { "blah" => "foo", "hello" => "world" } } }
+      after_filter["barg"]  = { :bargain => "niag", "blah" => mask, "bar" => { "bargain" => { "blah" => mask, "hello" => "world!" } } }
+
+      assert_equal after_filter, parameter_filter.filter(before_filter)
+    end
+  end
+
+  test "filter_param" do
+    parameter_filter = ActiveSupport::ParameterFilter.new(["foo", /bar/])
+    assert_equal "[FILTERED]", parameter_filter.filter_param("food", "secret vlaue")
+    assert_equal "[FILTERED]", parameter_filter.filter_param("baz.foo", "secret vlaue")
+    assert_equal "[FILTERED]", parameter_filter.filter_param("barbar", "secret vlaue")
+    assert_equal "non secret value", parameter_filter.filter_param("baz", "non secret value")
+  end
+
+  test "filter_param can work with empty filters" do
+    parameter_filter = ActiveSupport::ParameterFilter.new
+    assert_equal "bar", parameter_filter.filter_param("foo", "bar")
+  end
+
   test "parameter filter should maintain hash with indifferent access" do
     test_hashes = [
       [{ "foo" => "bar" }.with_indifferent_access, ["blah"]],
@@ -48,4 +93,13 @@ class ParameterFilterTest < ActiveSupport::TestCase
                          parameter_filter.filter(before_filter)
     end
   end
+
+  test "filter_param should return mask option when value is filtered" do
+    mask = Object.new.freeze
+    parameter_filter = ActiveSupport::ParameterFilter.new(["foo", /bar/], mask: mask)
+    assert_equal mask, parameter_filter.filter_param("food", "secret vlaue")
+    assert_equal mask, parameter_filter.filter_param("baz.foo", "secret vlaue")
+    assert_equal mask, parameter_filter.filter_param("barbar", "secret vlaue")
+    assert_equal "non secret value", parameter_filter.filter_param("baz", "non secret value")
+  end
 end