1905/nojira passion with context without block

Gemfile.lock

@@ -1,7 +1,7 @@
 PATH
   remote: .
   specs:
-    contextual_logger (0.2.1)
+    contextual_logger (0.3.0)
       json
 
 GEM

contextual_logger.gemspec

@@ -2,7 +2,7 @@
 
 Gem::Specification.new do |spec|
   spec.name        = 'contextual_logger'
-  spec.version     = '0.2.1'
+  spec.version     = '0.3.0'
   spec.license     = 'MIT'
   spec.date        = '2018-10-12'
   spec.summary     = 'Add context to your logger'

lib/contextual_logger.rb

@@ -1,26 +1,31 @@
 # frozen_string_literal: true
 
 require 'json'
+require_relative './contextual_logger/context/handler'
 
 module ContextualLogger
   def self.new(logger)
     logger.extend(self)
   end
 
   def global_context=(context)
-    Thread.current[THREAD_CONTEXT_NAMESPACE] = context
+    ContextualLogger::Context::Handler.new(context).set!
   end
 
   def with_context(context)
-    previous_context = Thread.current[THREAD_CONTEXT_NAMESPACE] || {}
-    Thread.current[THREAD_CONTEXT_NAMESPACE] = previous_context.merge(context)
-    yield if block_given?
+    context_handler = ContextualLogger::Context::Handler.new(current_context_for_thread.merge(context))
+    context_handler.set!
+    if block_given?
+      yield
+    else
+      context_handler
+    end
   ensure
-    Thread.current[THREAD_CONTEXT_NAMESPACE] = previous_context
+    context_handler.reset! if block_given?
   end
 
   def current_context_for_thread
-    Thread.current[THREAD_CONTEXT_NAMESPACE] || {}
+    ContextualLogger::Context::Handler.current_context
   end
 
   def format_message(severity, timestamp, progname, message, context)
@@ -81,8 +86,6 @@ def write_entry_to_log(severity, timestamp, progname, message, context)
 
   private
 
-  THREAD_CONTEXT_NAMESPACE = 'ContextualLoggerCurrentLoggingContext'
-
   def message_with_context(context, message, severity, timestamp, progname)
     context.merge(
       message: message,

lib/contextual_logger/context/handler.rb

@@ -0,0 +1,28 @@
+# frozen_string_literal: true
+
+module ContextualLogger
+  module Context
+    class Handler
+      THREAD_CONTEXT_NAMESPACE = 'ContextualLoggerCurrentLoggingContext'
+
+      attr_reader :previous_context, :context
+
+      def self.current_context
+        Thread.current[THREAD_CONTEXT_NAMESPACE] || {}
+      end
+
+      def initialize(context, previous_context: nil)
+        @previous_context = previous_context || self.class.current_context
+        @context = context
+      end
+
+      def set!
+        Thread.current[THREAD_CONTEXT_NAMESPACE] = context
+      end
+
+      def reset!
+        Thread.current[THREAD_CONTEXT_NAMESPACE] = previous_context
+      end
+    end
+  end
+end

spec/lib/context/handler_spec.rb

@@ -0,0 +1,32 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+require 'contextual_logger'
+
+describe ContextualLogger::Context::Handler do
+  let(:context) { { service: "hello_world", integration: "google" } }
+  subject(:handler) { ContextualLogger::Context::Handler.new(context) }
+
+  it { is_expected.to respond_to(:set!) }
+  it { is_expected.to respond_to(:reset!) }
+
+  it 'sets the thread context on set!' do
+    previous_context = ContextualLogger::Context::Handler.current_context
+    handler.set!
+
+    expect(ContextualLogger::Context::Handler.current_context).to_not eq(previous_context)
+    expect(ContextualLogger::Context::Handler.current_context).to eq(context)
+
+    handler.reset!
+  end
+
+  it 'resets the thread context on reset!' do
+    initial_context = ContextualLogger::Context::Handler.current_context
+    handler.set!
+    new_context = ContextualLogger::Context::Handler.current_context
+    handler.reset!
+
+    expect(ContextualLogger::Context::Handler.current_context).to_not eq(new_context)
+    expect(ContextualLogger::Context::Handler.current_context).to eq(initial_context)
+  end
+end

spec/lib/contextual_logger_spec.rb

@@ -8,6 +8,7 @@
   before do
     Time.now_override = Time.now
     @logger = ContextualLogger.new(Logger.new('/dev/null'))
+    @logger.global_context = {}
   end
 
   it 'should respond to with_context' do
@@ -169,6 +170,83 @@
         end
       end
     end
+
+    it 'returns the output of the block passed in' do
+      expect(@logger.with_context(service: 'test_service') { 6 }).to eq(6)
+    end
+  end
+
+  describe 'with_context without block' do
+    it 'returns a context handler' do
+      expect(@logger.with_context(service: 'test_service')).to be_a(ContextualLogger::Context::Handler)
+    end
+
+    it 'prints out the wrapper context with logging' do
+      expected_log_line = {
+        service: 'test_service',
+        message: 'this is a test',
+        severity: 'INFO',
+        timestamp: Time.now,
+        progname: nil
+      }.to_json
+
+      expect_any_instance_of(Logger::LogDevice).to receive(:write).with("#{expected_log_line}\n")
+
+      handler = @logger.with_context(service: 'test_service')
+      expect(@logger.info('this is a test')).to eq(true)
+      handler.reset!
+    end
+
+    it 'merges inline context into wrapper context when logging' do
+      expected_log_line = {
+        service: 'test_service',
+        file: 'this_file.json',
+        message: 'this is a test',
+        severity: 'INFO',
+        timestamp: Time.now,
+        progname: nil
+      }.to_json
+
+      expect_any_instance_of(Logger::LogDevice).to receive(:write).with("#{expected_log_line}\n")
+
+      handler = @logger.with_context(service: 'test_service')
+      expect(@logger.info('this is a test', file: 'this_file.json')).to eq(true)
+      handler.reset!
+    end
+
+    it 'takes inline context over wrapper context when logging' do
+      expected_log_line = {
+        service: 'test_service_2',
+        message: 'this is a test',
+        severity: 'INFO',
+        timestamp: Time.now,
+        progname: nil
+      }.to_json
+
+      expect_any_instance_of(Logger::LogDevice).to receive(:write).with("#{expected_log_line}\n")
+
+      handler = @logger.with_context(service: 'test_service')
+      expect(@logger.info('this is a test', service: 'test_service_2')).to eq(true)
+      handler.reset!
+    end
+
+    it 'combines tiered contexts when logging' do
+      expected_log_line = {
+        service: 'test_service',
+        file: 'this_file.json',
+        message: 'this is a test',
+        severity: 'INFO',
+        timestamp: Time.now,
+        progname: nil
+      }.to_json
+
+      expect_any_instance_of(Logger::LogDevice).to receive(:write).with("#{expected_log_line}\n")
+
+      handler1 = @logger.with_context(service: 'test_service')
+      @logger.with_context(file: 'this_file.json')
+      expect(@logger.info('this is a test')).to eq(true)
+      handler1.reset!
+    end
   end
 
   describe 'global_context' do