Add latest_version method for use Rubygems API, allow Plugin#version is empty for install

Gemfile.lock

@@ -7,6 +7,7 @@ PATH
       coffee-rails (~> 4.0.0)
       fluentd (= 0.10.46)
       haml-rails (~> 0.5.3)
+      httpclient
       i18n_generators (= 1.2.1)
       jbuilder (~> 2.0)
       jquery-rails (~> 3.1.0)
@@ -46,7 +47,6 @@ GEM
       tzinfo (~> 1.1)
     arel (5.0.1.20140414130214)
     bcrypt (3.1.7)
-    bson (1.10.0)
     builder (3.2.2)
     capybara (2.2.1)
       mime-types (>= 1.16)
@@ -74,9 +74,6 @@ GEM
     factory_girl_rails (4.4.1)
       factory_girl (~> 4.4.0)
       railties (>= 3.0.0)
-    fluent-plugin-mongo (0.7.3)
-      fluentd (~> 0.10.9)
-      mongo (>= 1.8.0)
     fluentd (0.10.46)
       cool.io (>= 1.1.1, < 2.0.0, != 1.2.0)
       http_parser.rb (>= 0.5.1, < 0.7.0)
@@ -95,6 +92,7 @@ GEM
     http-cookie (1.0.2)
       domain_name (~> 0.5)
     http_parser.rb (0.6.0)
+    httpclient (2.3.4.1)
     i18n (0.6.9)
     i18n_generators (1.2.1)
       mechanize
@@ -122,8 +120,6 @@ GEM
     mime-types (1.25.1)
     mini_portile (0.5.3)
     minitest (5.3.3)
-    mongo (1.10.0)
-      bson (~> 1.10.0)
     msgpack (0.5.8)
     multi_json (1.10.0)
     net-http-digest_auth (1.4)
@@ -215,7 +211,6 @@ DEPENDENCIES
   capybara (~> 2.2.1)
   database_cleaner (~> 1.2.0)
   factory_girl_rails
-  fluent-plugin-mongo (= 0.7.3)
   fluentd-ui!
   pry
   rake

app/controllers/plugins_controller.rb

@@ -20,7 +20,8 @@ class PluginsController < ApplicationController
   def plugins
     # TODO
     [
-      Plugin.new(gem_name: "fluent-plugin-mongo", version: "0.7.3")
+      Plugin.new(gem_name: "fluent-plugin-mongo", version: "0.7.3"),
+      Plugin.new(gem_name: "fluent-plugin-s3"),
     ]
   end
 

app/models/plugin.rb

@@ -1,4 +1,6 @@
 require "fileutils"
+require "json"
+require "httpclient"
 
 class Plugin
   class GemError < StandardError; end
@@ -14,21 +16,25 @@ class Plugin
   end
 
   def install!
-    if valid? && !installed?
-      if fluent_gem("install", gem_name, "-v", version)
-        File.open(gemfile_path, "a") do |f|
-          f.puts format_gemfile
+    unless installed?
+      self.version = latest_version unless version
+      if valid?
+        if fluent_gem("install", gem_name, "-v", version)
+          File.open(gemfile_path, "a") do |f|
+            f.puts format_gemfile
+          end
         end
       end
     end
   end
 
   def uninstall!
-    if valid? && installed?
+    if installed?
       # NOTE: do not uninstall gem actually for now. because it is not necessary, and slow job
+      # NOTE: should uninstall that situation: installed verions is A, self.version is NOT A.
       new_gemfile = ""
       File.open(gemfile_path).each_line do |line|
-        next if line.strip == format_gemfile
+        next if line.include?(%Q|gem "#{gem_name}"|)
         new_gemfile << line
       end
       File.open(gemfile_path, "w"){|f| f.write new_gemfile }
@@ -46,18 +52,34 @@ class Plugin
   end
 
   def installed?
-    File.read(gemfile_path).lines.map(&:strip).grep(format_gemfile).present?
+    self.class.installed.find do |plugin|
+      plugin.gem_name == gem_name
+    end
   end
 
   def format_gemfile
+    self.version = latest_version unless version
     %Q|gem "#{gem_name}", "#{version}"|
   end
 
+  def latest_version
+    res = HTTPClient.get("https://rubygems.org/api/v1/versions/#{gem_name}.json")
+    if res.code == 200
+      JSON.parse(res.body).map {|ver| Gem::Version.new ver["number"] }.max.to_s
+    end
+  end
+
   def self.gemfile_changed?
     # if true, rails server needs to restart }
     @initial_gemfile_content != File.read(gemfile_path)
   end
 
+  def self.installed
+    File.read(gemfile_path).scan(/"(.*?)", "(.*?)"/).map do |plugin|
+      new(gem_name: plugin[0], version: plugin[1])
+    end
+  end
+
   def self.gemfile_path
     if Rails.env == "test"
       gemfile_path = "/tmp/fluentd-ui-test-Gemfile.plugins" # can't create a file under Rails.root directory on Circle CI

fluentd-ui.gemspec

@@ -30,5 +30,6 @@ Gem::Specification.new do |spec|
   spec.add_dependency 'jquery-rails', "~> 3.1.0"
   spec.add_dependency 'jbuilder', '~> 2.0'
   spec.add_dependency "bundler", "~> 1.5"
+  spec.add_dependency "httpclient"
 
 end