Initial commit

Author: sunilvigneshr

.gitignore

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+.gem
+varlog-0.0.1.gem

Gemfile

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+# frozen_string_literal: true
+# A sample Gemfile
+source "https://rubygems.org"
+
+# gem "rails"
+gem "request_store"

example/Gemfile

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+source "https://rubygems.org"
+
+gem "sinatra"

example/server.rb

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+require 'sinatra'
+require 'net/http'
+require 'varlog'
+
+configure do
+  use Varlog::Middleware
+end
+
+get '/status' do
+  uri = URI.parse("http://google.com/")
+  http = Net::HTTP.new(uri.host, uri.port)
+  request = Net::HTTP::Get.new(uri.request_uri)
+  response = http.request(request)
+  response.body
+end

lib/varlog.rb

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+require 'varlog/middleware'
+require 'varlog/interceptor'
+require 'varlog/version'

lib/varlog/collector.rb

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+module Varlog
+  module Collector
+    class << self
+      def collect(event)
+        p event
+      end
+    end
+  end
+end

lib/varlog/events.rb

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+require 'securerandom'
+
+module Varlog
+  class HTTPRequestEvent
+
+    def initialize(parent_id, timestamp, method, endpoint)
+      self.id = SecureRandom.uuid()
+      self.parent_id = parent_id
+      self.timestamp = timestamp
+      self.endpoint = endpoint
+      self.type = type
+      self.schema = "HTTPRequest"
+    end
+
+  end
+
+  class HTTPResponseEvent
+
+    def initialize(parent_id, timestamp, status, endpoint, rtt)
+      self.id = SecureRandom.uuid()
+      self.parent_id = parent_id
+      self.timestamp = timestamp
+      self.endpoint = endpoint
+      self.type = type
+      self.rtt = rtt
+      self.schema = "HTTPResponse"
+    end
+
+  end
+
+  class MessageEvent
+
+    def initialize(parent_id, timestamp, message)
+      self.id = SecureRandom.uuid()
+      self.timestamp = timestamp
+      self.endpoint = endpoint
+      self.message = message
+      self.schema = "Message"
+    end
+
+  end
+
+end

lib/varlog/interceptor.rb

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+require 'request_store'
+
+module Net
+  class HTTP
+    alias_method :orig_request, :request
+
+    def request(req, body = nil)
+      trace_id = RequestStore[:trace_id]
+      timestamp = Time.now.to_i
+      endpoint = req.path
+
+      request_event = new Varlog::HTTPRequestEvent(trace_id, timestamp, req.method, endpoint)
+      Collector.collect(request_event)
+      rtt = Bechmark.realtime do
+        @response = orig_request(req, body)
+      end
+      response_event = new Varlog::HTTPResponseEvent(trace_id, timestamp, res.code, endpoint, rtt)
+      Collector.collect(response_event)
+
+      @response
+    end
+
+  end
+end

lib/varlog/middleware.rb

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+require 'request_store'
+require 'securerandom'
+
+module Varlog
+  class Middleware
+
+    def initialize(app)
+      @app = app
+    end
+
+    def call(env)
+      RequestStore.begin!
+      RequestStore[:trace_id] = SecureRandom.uuid
+      @app.call(env)
+    ensure
+      RequestStore.end!
+      RequestStore.clear!
+    end
+
+  end
+end

lib/varlog/version.rb

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+module Varlog
+  VERSION = "0.0.1"
+end