Rename default_attributes parameter

Use `attributes` instead of `default_attributes`.

lib/appsignal/logger.rb

@@ -20,21 +20,23 @@ class Logger < ::Logger
       FATAL => 7
     }.freeze
 
-    attr_reader :level, :default_attributes
+    attr_reader :level
 
     # Create a new logger instance
     #
     # @param group Name of the group for this logger.
-    # @param level Log level to filter with
+    # @param level Minimum log level to report. Log lines below this level will be ignored.
+    # @param format Format to use to parse log line attributes.
+    # @param attributes Default attributes for all log lines.
     # @return [void]
-    def initialize(group, level: INFO, format: PLAINTEXT, default_attributes: {})
+    def initialize(group, level: INFO, format: PLAINTEXT, attributes: {})
       raise TypeError, "group must be a string" unless group.is_a? String
 
       @group = group
       @level = level
       @format = format
       @mutex = Mutex.new
-      @default_attributes = default_attributes
+      @default_attributes = attributes
     end
 
     # We support the various methods in the Ruby
@@ -157,6 +159,8 @@ def silence(_severity = ERROR, &block)
 
     private
 
+    attr_reader :default_attributes
+
     def add_with_attributes(severity, message, group, attributes)
       Thread.current[:appsignal_logger_attributes] = default_attributes.merge!(attributes)
       add(severity, message, group)

spec/lib/appsignal/logger_spec.rb

@@ -184,7 +184,7 @@
 
   describe "a logger with default attributes" do
     it "adds the attributes when a message is logged" do
-      logger = Appsignal::Logger.new("group", :default_attributes => { :some_key => "some_value" })
+      logger = Appsignal::Logger.new("group", :attributes => { :some_key => "some_value" })
 
       expect(Appsignal::Extension).to receive(:log).with("group", 6, 0, "Some message",
         Appsignal::Utils::Data.generate({ :other_key => "other_value", :some_key => "some_value" }))