Merge pull request #15 from epimorphics/dev

Release 0.2.0

CHANGELOG.md

@@ -0,0 +1,13 @@
+# Changelog for the JSON Rails Logger gem
+
+## 0.2.0 - 2021-02-01 (Bogdan)
+
+- Platform related fields are now grouped together inside the 'rails' field
+- Request ID is now present in every log message
+- MIT license file added to the repo
+- Added readme file with usage instructions
+
+## 0.1.0 - 2021-01-26 (Bogdan)
+
+- This is an initial release, contains a simple JSON Rails Logger
+  with some customisation applied to it

Gemfile.lock

@@ -1,7 +1,7 @@
 PATH
   remote: .
   specs:
-    json_rails_logger (0.1.0)
+    json_rails_logger (0.2.0)
       json
       lograge
       railties

LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2021 Epimorphics Ltd
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

README.md

@@ -1,2 +1,25 @@
 # json-rails-logger
-A custom rails logger that outputs json instead of raw text
+
+A custom rails logger that outputs JSON instead of raw text. As an extra the
+logger also saves the `request_id` for any log message, in the returned JSON
+object. The formatter has a couple of changes that are down to preference, but
+these don't affect the functionality in any way. This gem can be used with any
+Rails app using the installation steps below.
+
+## Installation
+
+In your Rails app, add this to your gemfile:\
+`gem 'json_rails_logger', git: '[email protected]:epimorphics/json-rails-logger.git'`
+
+And this to your environment config:\
+`config.logger = JsonRailsLogger::Logger.new(STDOUT)`
+
+## Running the tests
+
+Tests are located in the `./test/` folder.
+
+After cloning the repo, first execute:\
+`bundle install`
+
+To run the tests, use:\
+`rake test`

lib/json_rails_logger/constants.rb

@@ -0,0 +1,5 @@
+# frozen_string_literal: true
+
+module JsonRailsLogger
+  REQUEST_ID = :request_id
+end

lib/json_rails_logger/json_formatter.rb

@@ -3,18 +3,21 @@
 module JsonRailsLogger
   # This class is the json formatter for our logger
   class JsonFormatter < ::Logger::Formatter
+    COMMON_KEYS = %w[
+      method path status duration
+    ].freeze
+
     def call(severity, timestamp, _progname, raw_msg)
       sev = process_severity(severity)
       timestp = process_timestamp(timestamp)
       msg = process_message(raw_msg)
+      new_msg = format_message(msg)
 
-      payload = {
-        level: sev,
-        timestamp: timestp,
-        rails_environment: ::Rails.env
-      }
+      payload = { level: sev,
+                  timestamp: timestp }
 
-      payload.merge!(msg)
+      payload.merge!(x_request_id.to_h)
+      payload.merge!(new_msg.to_h)
 
       "#{payload.to_json}\n"
     end
@@ -29,6 +32,11 @@ def process_timestamp(timestamp)
       format_datetime(timestamp)
     end
 
+    def x_request_id
+      x_request_id = Thread.current[JsonRailsLogger::REQUEST_ID]
+      { 'x-request-id': x_request_id } if x_request_id
+    end
+
     def process_message(raw_msg)
       msg = normalize_message(raw_msg)
 
@@ -41,6 +49,26 @@ def process_message(raw_msg)
       { message: msg.strip }
     end
 
+    def format_message(msg)
+      new_msg = { rails: { environment: ::Rails.env } }
+
+      return msg.merge(new_msg) if string_message_field?(msg)
+
+      split_msg = msg.partition { |k, _v| COMMON_KEYS.include?(k.to_s) }
+                     .map(&:to_h)
+
+      new_msg.merge!(split_msg[0])
+      new_msg[:rails].merge!(split_msg[1])
+
+      new_msg
+    end
+
+    def string_message_field?(msg)
+      msg.is_a?(Hash) &&
+        msg.length == 1 &&
+        msg.fetch(:message, nil).is_a?(String)
+    end
+
     def normalize_message(raw_msg)
       return raw_msg unless raw_msg.is_a?(String)
 

lib/json_rails_logger/railtie.rb

@@ -1,5 +1,7 @@
 # frozen_string_literal: true
 
+require_relative 'request_id_middleware'
+
 module JsonRailsLogger
   # This class is used to configure and setup lograge, as well as our gem
   class Railtie < Rails::Railtie
@@ -15,5 +17,10 @@ class Railtie < Rails::Railtie
       JsonRailsLogger.setup(app) if JsonRailsLogger.enabled?(app)
       Lograge.setup(app) if JsonRailsLogger.enabled?(app)
     end
+
+    initializer 'railtie.configure_rails_initialization' do |app|
+      app.middleware.insert_after(ActionDispatch::RequestId,
+                                  JsonRailsLogger::RequestIdMiddleware)
+    end
   end
 end

lib/json_rails_logger/request_id_middleware.rb

@@ -0,0 +1,21 @@
+# frozen_string_literal: true
+
+require_relative 'constants'
+
+module JsonRailsLogger
+  # Middleware that saves the request_id into a constant
+  # and clears it after usage in the formatter
+  class RequestIdMiddleware
+    def initialize(app)
+      @app = app
+    end
+
+    def call(env)
+      request_id = env['action_dispatch.request_id']
+      Thread.current[JsonRailsLogger::REQUEST_ID] = request_id
+      @app.call(env)
+    ensure
+      Thread.current[JsonRailsLogger::REQUEST_ID] = nil
+    end
+  end
+end

lib/json_rails_logger/version.rb

@@ -2,7 +2,7 @@
 
 module JsonRailsLogger
   MAJOR = 0
-  MINOR = 1
+  MINOR = 2
   FIX = 0
   VERSION = "#{MAJOR}.#{MINOR}.#{FIX}"
 end

test/formatter_test.rb

@@ -52,8 +52,8 @@
     _(log_output).must_be_kind_of(String)
 
     json_output = JSON.parse(log_output)
-    _(json_output['user_agent']).must_equal('Faraday v1.3.0')
-    _(json_output['accept']).must_equal('application/json')
+    _(json_output['rails']['user_agent']).must_equal('Faraday v1.3.0')
+    _(json_output['rails']['accept']).must_equal('application/json')
   end
 
   it 'should correctly format the timestamp' do