Ensure filtered params aren't revealed in sql

lib/rails_semantic_logger/active_record/log_subscriber.rb

@@ -54,11 +54,25 @@ def sql(event)
 
       # When multiple values are received for a single bound field, it is converted into an array
       def add_bind_value(binds, key, value)
-        key        = key.downcase.to_sym unless key.nil?
-        value      = (Array(binds[key]) << value) if binds.key?(key)
+        key = key.downcase.to_sym unless key.nil?
+
+        if rails_filter_params_include?(key)
+          value = "[FILTERED]"
+        elsif binds.key?(key)
+          value = (Array(binds[key]) << value)
+        end
+
         binds[key] = value
       end
 
+      def rails_filter_params_include?(key)
+        filter_parameters = Rails.configuration.filter_parameters
+
+        return filter_parameters.first.match? key if filter_parameters.first.is_a? Regexp
+
+        filter_parameters.include? key
+      end
+
       def logger
         self.class.logger
       end

test/active_record_test.rb

@@ -87,6 +87,62 @@ class ActiveRecordTest < Minitest::Test
         assert_instance_of Integer, messages[0].payload[:allocations] if Rails.version.to_i >= 6
       end
 
+      it "filtered bind value" do
+        filter_params_setting true, %i[name] do
+          expected_sql =
+            if Rails.version.to_f >= 5.2
+              "SELECT #{extra_space}\"samples\".* FROM \"samples\" WHERE \"samples\".\"name\" = ? ORDER BY \"samples\".\"id\" ASC LIMIT ?"
+            else
+              "SELECT  \"samples\".* FROM \"samples\" WHERE \"samples\".\"name\" = ? ORDER BY \"samples\".\"id\" ASC LIMIT ?"
+            end
+
+          messages = semantic_logger_events do
+            Sample.where(name: "Jack").first
+          end
+          assert_equal 1, messages.count, messages
+
+          assert_semantic_logger_event(
+            messages[0],
+            level:            :debug,
+            name:             "ActiveRecord",
+            message:          "Sample Load",
+            payload_includes: {
+              sql:   expected_sql,
+              binds: {name: "[FILTERED]", limit: 1}
+            }
+          )
+          assert_instance_of Integer, messages[0].payload[:allocations] if Rails.version.to_i >= 6
+        end
+      end
+
+      it "filtered bind value when filter_parameters set as regex" do
+        filter_params_regex_setting true, %i[name] do
+          expected_sql =
+            if Rails.version.to_f >= 5.2
+              "SELECT #{extra_space}\"samples\".* FROM \"samples\" WHERE \"samples\".\"name\" = ? ORDER BY \"samples\".\"id\" ASC LIMIT ?"
+            else
+              "SELECT  \"samples\".* FROM \"samples\" WHERE \"samples\".\"name\" = ? ORDER BY \"samples\".\"id\" ASC LIMIT ?"
+            end
+
+          messages = semantic_logger_events do
+            Sample.where(name: "Jack").first
+          end
+          assert_equal 1, messages.count, messages
+
+          assert_semantic_logger_event(
+            messages[0],
+            level:            :debug,
+            name:             "ActiveRecord",
+            message:          "Sample Load",
+            payload_includes: {
+              sql:   expected_sql,
+              binds: {name: "[FILTERED]", limit: 1}
+            }
+          )
+          assert_instance_of Integer, messages[0].payload[:allocations] if Rails.version.to_i >= 6
+        end
+      end
+
       it "multiple bind values" do
         skip "Not applicable to older rails" if Rails.version.to_f <= 5.1
 

test/test_helper.rb

@@ -23,3 +23,27 @@
 Minitest::Test.include SemanticLogger::Test::Minitest
 
 ActionMailer::Base.delivery_method = :test
+
+def filter_params_setting(value, user_defined_params, &block)
+  original_value = Rails.configuration.filter_parameters
+  Rails.configuration.filter_parameters = user_defined_params
+  block.call
+ensure
+  Rails.configuration.filter_parameters = original_value
+end
+
+def filter_params_regex_setting(value, user_defined_params, &block)
+  original_value = Rails.configuration.filter_parameters
+
+  Rails.configuration.filter_parameters += user_defined_params
+
+  filter_params_regex = Rails.configuration.filter_parameters.map do |key|
+    "(?i:#{key})"
+  end.join("|")
+
+  Rails.configuration.filter_parameters = [/(?-mix:#{filter_params_regex})/]
+
+  block.call
+ensure
+  Rails.configuration.filter_parameters = original_value
+end