TECH-12593:make global_context global, but just for that logger instance

CHANGELOG.md

@@ -4,6 +4,11 @@ Inspired by [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 Note: this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [1.2.0] - Unreleased
+### Changed
+- Changed global_context to be stored inside the logger.
+- Changed current_context to be stored in a Thread/Fiber-local variable that is unique per instance of the logger.
+
 ## [1.1.1] - 2022-11-29
 ### Added
 - Bug fix for registering regex
@@ -99,15 +104,3 @@ are already passed to the formatter as arguments so that the formatter can decid
 ### Added
  - Extracted `ContextualLogger.normalize_log_level` into a public class method so we can call it elsewhere where we allow log_level to be
    configured to text values like 'debug'.
-
-[1.0.0]: https://github.com/Invoca/contextual_logger/compare/v0.11.0...v1.0.0
-[0.11.0]: https://github.com/Invoca/contextual_logger/compare/v0.10.0...v0.11.0
-[0.10.0]: https://github.com/Invoca/contextual_logger/compare/v0.9.1...v0.10.0
-[0.9.1]: https://github.com/Invoca/contextual_logger/compare/v0.9.0...v0.9.1
-[0.9.0]: https://github.com/Invoca/contextual_logger/compare/v0.8.0...v0.9.0
-[0.8.0]: https://github.com/Invoca/contextual_logger/compare/v0.7.0...v0.8.0
-[0.7.0]: https://github.com/Invoca/contextual_logger/compare/v0.6.1...v0.7.0
-[0.6.1]: https://github.com/Invoca/contextual_logger/compare/v0.6.0...v0.6.1
-[0.6.0]: https://github.com/Invoca/contextual_logger/compare/v0.5.1...v0.6.0
-[0.5.1]: https://github.com/Invoca/contextual_logger/compare/v0.5.0...v0.5.1
-[0.5.0]: https://github.com/Invoca/contextual_logger/compare/v0.4.0...v0.5.0

Gemfile.lock

@@ -1,19 +1,19 @@
 PATH
   remote: .
   specs:
-    contextual_logger (1.1.1)
+    contextual_logger (1.2.0.colin.4)
       activesupport
       json
 
 GEM
   remote: https://rubygems.org/
   specs:
-    activesupport (7.0.4.3)
+    activesupport (7.0.7.2)
       concurrent-ruby (~> 1.0, >= 1.0.2)
       i18n (>= 1.6, < 2)
       minitest (>= 5.1)
       tzinfo (~> 2.0)
-    appraisal (2.4.1)
+    appraisal (2.5.0)
       bundler
       rake
       thor (>= 0.14.0)
@@ -29,18 +29,20 @@ GEM
       tins (~> 1.6)
     diff-lcs (1.5.0)
     docile (1.4.0)
-    i18n (1.12.0)
+    i18n (1.14.1)
       concurrent-ruby (~> 1.0)
     json (2.6.3)
     method_source (1.0.0)
-    minitest (5.18.0)
+    minitest (5.19.0)
     parallel (1.23.0)
-    parser (3.2.2.0)
+    parser (3.2.2.3)
       ast (~> 2.4.1)
+      racc
     powerpack (0.1.3)
     pry (0.14.2)
       coderay (~> 1.1)
       method_source (~> 1.0)
+    racc (1.7.1)
     rainbow (3.1.1)
     rake (13.0.6)
     rspec (3.12.0)
@@ -49,13 +51,13 @@ GEM
       rspec-mocks (~> 3.12.0)
     rspec-core (3.12.2)
       rspec-support (~> 3.12.0)
-    rspec-expectations (3.12.2)
+    rspec-expectations (3.12.3)
       diff-lcs (>= 1.2.0, < 2.0)
       rspec-support (~> 3.12.0)
-    rspec-mocks (3.12.5)
+    rspec-mocks (3.12.6)
       diff-lcs (>= 1.2.0, < 2.0)
       rspec-support (~> 3.12.0)
-    rspec-support (3.12.0)
+    rspec-support (3.12.1)
     rspec_junit_formatter (0.6.0)
       rspec-core (>= 2, < 4, != 2.12.0)
     rubocop (0.54.0)
@@ -79,7 +81,7 @@ GEM
     sync (0.5.0)
     term-ansicolor (1.7.1)
       tins (~> 1.0)
-    thor (1.2.1)
+    thor (1.2.2)
     tins (1.32.1)
       sync
     tzinfo (2.0.6)
@@ -105,4 +107,4 @@ DEPENDENCIES
   ruby-prof-flamegraph
 
 BUNDLED WITH
-   2.2.29
+   2.3.22

contextual_logger.gemspec

@@ -19,6 +19,6 @@ Gem::Specification.new do |spec|
     "allowed_push_host" => "https://rubygems.org"
   }
 
-  spec.add_runtime_dependency 'json'
-  spec.add_runtime_dependency 'activesupport'
+  spec.add_dependency 'json'
+  spec.add_dependency 'activesupport'
 end

lib/contextual_logger.rb

@@ -4,7 +4,8 @@
 require 'active_support/core_ext/module/delegation'
 require 'json'
 require_relative './contextual_logger/redactor'
-require_relative './contextual_logger/context/handler'
+require_relative './contextual_logger/context'
+require_relative './contextual_logger/context_handler'
 
 module ContextualLogger
   LOG_LEVEL_NAMES_TO_SEVERITY =
@@ -43,31 +44,40 @@ def normalize_message(message)
   end
 
   module LoggerMixin
+    include Context
+
     delegate :register_secret, :register_secret_regex, to: :redactor
 
+    def global_context
+      @global_context ||= {}.freeze
+    end
+
     def global_context=(context)
-      Context::Handler.new(context).set!
+      @global_context = context.freeze
+    end
+
+    def current_context
+      current_context_override || global_context
     end
 
+    # TODO: Deprecate current_context_for_thread in v2.0.
+    alias current_context_for_thread current_context
+
     def with_context(context)
-      context_handler = Context::Handler.new(current_context_for_thread.deep_merge(context))
-      context_handler.set!
+      previous_context_override = current_context_override
+      self.current_context_override = current_context.deep_merge(context)
       if block_given?
         begin
           yield
         ensure
-          context_handler.reset!
+          self.current_context_override = previous_context_override
         end
       else
-        # If no block given, the context handler is returned to the caller so they can handle reset! themselves.
-        context_handler
+        # If no block given, return context handler to the caller so they can call reset! themselves.
+        ContextHandler.new(self, previous_context_override)
       end
     end
 
-    def current_context_for_thread
-      Context::Handler.current_context
-    end
-
     # In the methods generated below, we assume that presence of context means new code that is
     # aware of ContextualLogger...and that that code never uses progname.
     # This is important because we only get 3 args total (not including &block) passed to `add`,
@@ -117,7 +127,7 @@ def add(arg_severity, arg1 = nil, arg2 = nil, **context)   # Ruby will prefer to
           message = arg1
           progname = arg2 || @progname
         end
-        write_entry_to_log(severity, Time.now, progname, message, context: current_context_for_thread.deep_merge(context))
+        write_entry_to_log(severity, Time.now, progname, message, context: current_context.deep_merge(context))
       end
 
       true

lib/contextual_logger/context.rb

@@ -0,0 +1,18 @@
+# frozen_string_literal: true
+
+module ContextualLogger
+  module Context
+    def thread_context_for_logger_instance
+      # We include the object_id here to make these thread/fiber locals unique per logger instance.
+      @thread_context_for_logger_instance ||= "ContextualLogger::Context.context_for_#{object_id}".to_sym
+    end
+
+    def current_context_override
+      Thread.current[thread_context_for_logger_instance]
+    end
+
+    def current_context_override=(context_override)
+      Thread.current[thread_context_for_logger_instance] = context_override.freeze
+    end
+  end
+end

lib/contextual_logger/context_handler.rb

@@ -0,0 +1,14 @@
+# frozen_string_literal: true
+
+module ContextualLogger
+  class ContextHandler
+    def initialize(instance, previous_context_override)
+      @instance = instance
+      @previous_context_override = previous_context_override
+    end
+
+    def reset!
+      @instance.current_context_override = @previous_context_override
+    end
+  end
+end

lib/contextual_logger/logger_with_context.rb

@@ -19,6 +19,10 @@ def initialize(logger, context, level: nil)
       @merged_context_cache = {}  # so we don't have to merge every time
     end
 
+    def global_context
+      @logger.global_context
+    end
+
     def level
       @override_level || @logger.level
     end

lib/contextual_logger/version.rb

@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 
 module ContextualLogger
-  VERSION = '1.1.1'
+  VERSION = '1.2.0.colin.4'
 end

spec/lib/contextual_logger/context_handler_spec.rb

@@ -0,0 +1,26 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+require 'contextual_logger'
+
+class ContextualLoggerContextHandlerSpecContainer
+  include ::ContextualLogger::Context
+end
+
+RSpec.describe ContextualLogger::ContextHandler do
+  let(:context) { { service: { name: 'tts', description: 'TTS' }, integration: "google" } }
+  let(:context2) { { service: { description: 'Context 2' }, integration: "google" } }
+
+  let(:instance) { ContextualLoggerContextHandlerSpecContainer.new }
+
+  subject(:handler) { described_class.new(instance, context) }
+
+  it { is_expected.to respond_to(:reset!) }
+
+  it 'resets the thread context on reset!' do
+    instance.current_context_override = context2
+    handler.reset!
+
+    expect(instance.current_context_override).to eq(context)
+  end
+end

spec/lib/contextual_logger/context_spec.rb

@@ -0,0 +1,66 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+require 'contextual_logger'
+
+class ContextualLoggerContextSpecContainer
+  include ::ContextualLogger::Context
+end
+
+RSpec.describe ContextualLogger::Context do
+  let(:context) { { service: { name: 'tts', description: 'TTS' }, integration: "google" } }
+  let(:context2) { { service: { description: 'Context 2' }, integration: "google" } }
+  let(:context3) { { service: { name: 'Context 3' } } }
+
+  let(:instance) { ContextualLoggerContextSpecContainer.new }
+
+  describe 'mixin methods' do
+    describe 'current_context_override/current_context_override=' do
+      it 'can be set with current_context_override=, separately per Fiber/Thread' do
+        instance.current_context_override = context
+
+        thread =
+          Thread.new do
+            instance.current_context_override = context2
+            instance.current_context_override
+          end
+
+        fiber =
+          Fiber.new do
+            instance.current_context_override = context3
+            instance.current_context_override
+          end
+
+        fiber_override = fiber.resume
+        thread_override = thread.value
+
+        expect(instance.current_context_override).to eq(context)
+        expect(thread_override).to eq(context2)
+        expect(fiber_override).to eq(context3)
+      end
+
+      it 'the current_context_override= values are separate per containing instance' do
+        instance.current_context_override = context
+        instance2 = ContextualLoggerContextSpecContainer.new
+        instance2.current_context_override = context2
+
+        expect(instance.current_context_override).to eq(context)
+        expect(instance2.current_context_override).to eq(context2)
+      end
+
+      it 'freezes the context_override when set' do
+        instance.current_context_override = {}
+
+        expect do
+          instance.current_context_override[:extra] = 'value'
+        end.to raise_exception(RuntimeError, /can't modify frozen/)
+      end
+
+      it 'returns nil when set to nil' do
+        instance.current_context_override = nil
+
+        expect(instance.current_context_override).to be_nil
+      end
+    end
+  end
+end