Rakefile in embulk-input-jira-0.0.2 vs Rakefile in embulk-input-jira-0.0.3

@@ -1,10 +1,11 @@
 require "bundler/gem_tasks"
 require 'rspec/core/rake_task'
 require "json"
 require "pathname"
 require "open-uri"
+require File.expand_path("../lib/embulk/input/jira/version.rb", __FILE__)
 
 
 task default: :spec
 
 desc "Run all examples"
@@ -14,17 +15,16 @@
 
 namespace :release do
   desc "Add header of now version release to ChangeLog and bump up version"
   task :prepare do
     root_dir = Pathname.new(File.expand_path("../", __FILE__))
-    version_file = root_dir.join("VERSION")
     changelog_file = root_dir.join("CHANGELOG.md")
 
     system("git fetch origin")
 
     # detect merged PR
-    old_version = version_file.read.strip
+    old_version = Embulk::Input::Jira::VERSION
     pr_numbers = `git log v#{old_version}..origin/master --oneline`.scan(/#[0-9]+/)
 
     if !$?.success? || pr_numbers.empty?
       puts "Detecting PR failed. Please confirm if any PR were merged after the latest release."
       exit(false)
@@ -36,11 +36,11 @@
 
     # Update ChangeLog
     pr_descriptions = pr_numbers.map do |number|
       body = open("https://api.github.com/repos/treasure-data/embulk-input-jira/issues/#{number.gsub("#", "")}").read
       payload = JSON.parse(body)
-      "* [] #{payload["title"]} [#{number}](https://github.com/treasure-data/embulk-input-jira/pull/#{number.gsub('#', '')}) "
+      "* [] #{payload["title"]} [#{number}](https://github.com/treasure-data/embulk-input-jira/pull/#{number.gsub('#', '')})"
     end.join("\n")
 
     new_changelog = <<-HEADER
 ## #{new_version} - #{Time.now.strftime("%Y-%m-%d")}
 #{pr_descriptions}
@@ -49,10 +49,14 @@
 HEADER
 
     File.open(changelog_file, "w") {|f| f.write(new_changelog) }
 
     # Update version.rb
-    File.open(version_file, "w") {|f| f.write new_version }
+    version_file = root_dir.join("./lib/embulk/input/jira/version.rb")
+    old_content = version_file.read
+    File.open(version_file, "w") do |f|
+      f.write old_content.gsub(old_version, new_version)
+    end
 
     # Update Gemfile.lock
     system("bundle install")
 
     puts "ChangeLog, version and Gemfile.lock were updated. New version is #{new_version}."