Add support for backend stores for config

Gemfile.lock

@@ -1,8 +1,9 @@
 PATH
   remote: .
   specs:
-    riemann-dash (0.2.5)
+    riemann-dash (0.2.8)
       erubis (>= 2.7.0)
+      fog
       multi_json (= 1.3.6)
       riemann-client (>= 0.0.7)
       sass (>= 3.1.14)
@@ -12,34 +13,55 @@ PATH
 GEM
   remote: https://rubygems.org/
   specs:
-    beefcake (0.3.7)
+    beefcake (0.5.0)
+    builder (3.2.2)
     coderay (1.0.9)
     daemons (1.1.9)
     erubis (2.7.0)
     eventmachine (1.0.3)
+    excon (0.31.0)
+    fog (1.19.0)
+      builder
+      excon (~> 0.31.0)
+      formatador (~> 0.2.0)
+      mime-types
+      multi_json (~> 1.0)
+      net-scp (~> 1.1)
+      net-ssh (>= 2.1.3)
+      nokogiri (~> 1.5)
+      ruby-hmac
+    formatador (0.2.4)
     method_source (0.8.1)
+    mime-types (2.0)
+    mini_portile (0.5.2)
     mtrc (0.0.4)
     multi_json (1.3.6)
+    net-scp (1.1.2)
+      net-ssh (>= 2.6.5)
+    net-ssh (2.7.0)
+    nokogiri (1.6.1)
+      mini_portile (~> 0.5.0)
     pry (0.9.12)
       coderay (~> 1.0.5)
       method_source (~> 0.8)
       slop (~> 3.4)
     rack (1.5.2)
-    rack-protection (1.5.0)
+    rack-protection (1.5.2)
       rack
     riemann-client (0.2.2)
       beefcake (>= 0.3.5)
       mtrc (>= 0.0.4)
       trollop (>= 1.16.2)
-    sass (3.2.7)
-    sinatra (1.3.6)
+    ruby-hmac (0.4.0)
+    sass (3.3.2)
+    sinatra (1.4.4)
       rack (~> 1.4)
-      rack-protection (~> 1.3)
-      tilt (~> 1.3, >= 1.3.3)
+      rack-protection (~> 1.4)
+      tilt (~> 1.3, >= 1.3.4)
     slop (3.4.3)
-    thin (1.5.1)
+    thin (1.6.2)
       daemons (>= 1.0.9)
-      eventmachine (>= 0.12.6)
+      eventmachine (>= 1.0.0)
       rack (>= 1.0.0)
     tilt (1.4.1)
     trollop (2.0)

lib/riemann/dash.rb

@@ -1,6 +1,8 @@
 require 'rubygems'
 require 'sinatra/base'
 require 'riemann/dash/version'
-require 'riemann/dash/config'
 require 'riemann/dash/browser_config'
+require 'riemann/dash/browser_config/file'
+require 'riemann/dash/browser_config/s3'
+require 'riemann/dash/config'
 require 'riemann/dash/app'

lib/riemann/dash/app.rb

@@ -26,6 +26,7 @@ def self.load(filename)
         config.load_controllers
         config.setup_views
         config.setup_public_dir
+        config.setup_storage_backend
       end
     end
   end

lib/riemann/dash/browser_config.rb

@@ -3,6 +3,14 @@ module Riemann::Dash::BrowserConfig
   require 'fileutils'
   require 'pp'
 
+  def self.backend
+    @backend
+  end
+
+  def self.backend=(backend)
+    @backend = backend
+  end
+
   # TODO: this is gonna take significant restructuring of the dashboard itself,
   # but we should move to http://arxiv.org/abs/1201.1784 or equivalent CRDTs.
 
@@ -54,35 +62,11 @@ def self.merge_configs(a, b)
             'workspaces'  => merge_workspaces(a['workspaces'], b['workspaces'])
   end
 
-
-  def self.read(config)
-    if File.exists? config.ws_config_file
-      File.open(config.ws_config_file, 'r') do |f|
-        f.flock File::LOCK_SH
-        f.read
-      end
-    else
-      MultiJson.encode({})
-    end
+  def self.read
+    backend.read
   end
 
-  def self.update(config, update)
-    update = MultiJson.decode update
-
-    # Read old config
-    old = MultiJson.decode read(config)
-
-    new = merge_configs update, old
-
-    # Save new config
-    FileUtils.mkdir_p File.dirname(config.ws_config_file)
-    begin
-      File.open(config.ws_config_file, File::RDWR|File::CREAT, 0644) do |f|
-        f.flock File::LOCK_EX
-        f.write(MultiJson.encode(new, :pretty => true))
-        f.flush
-        f.truncate f.pos
-      end
-    end
+  def self.update(update)
+    backend.update(update)
   end
 end

lib/riemann/dash/browser_config/file.rb

@@ -0,0 +1,39 @@
+class Riemann::Dash::BrowserConfig::File
+  require 'multi_json'
+  require 'fileutils'
+
+  def initialize(path)
+    @path = path
+  end
+
+  def read
+    if ::File.exists? @path
+      ::File.open(@path, 'r') do |f|
+        f.flock ::File::LOCK_SH
+        f.read
+      end
+    else
+      MultiJson.encode({})
+    end
+  end
+
+  def update(update)
+    update = MultiJson.decode update
+
+    # Read old config
+    old = MultiJson.decode read
+
+    new = Riemann::Dash::BrowserConfig.merge_configs update, old
+
+    # Save new config
+    FileUtils.mkdir_p ::File.dirname(@path)
+    begin
+      ::File.open(@path, ::File::RDWR|::File::CREAT, 0644) do |f|
+        f.flock ::File::LOCK_EX
+        f.write(MultiJson.encode(new, :pretty => true))
+        f.flush
+        f.truncate f.pos
+      end
+    end
+  end
+end

lib/riemann/dash/browser_config/s3.rb

@@ -0,0 +1,30 @@
+class Riemann::Dash::BrowserConfig::S3
+  require 'multi_json'
+  require 'fog'
+
+  def initialize(bucket, path, config = {})
+    @bucket = bucket
+    @path   = path
+    @config = config
+
+    @storage = Fog::Storage::AWS.new(config)
+  end
+
+  def read
+    begin
+      @storage.get_object(@bucket, @path).body
+    rescue Excon::Errors::NotFound
+      MultiJson.encode({})
+    end
+  end
+
+  def update(update)
+    update = MultiJson.decode update
+
+    # Read old config
+    old = MultiJson.decode read
+
+    new = Riemann::Dash::BrowserConfig.merge_configs update, old
+    @storage.put_object @bucket, @path, MultiJson.encode(new, :pretty => true)
+  end
+end

lib/riemann/dash/config.rb

@@ -1,4 +1,6 @@
 class Riemann::Dash::Config
+  require 'uri'
+
   attr_accessor :config_path
   attr_accessor :store
 
@@ -62,6 +64,19 @@ def setup_public_dir
     Riemann::Dash::App.use Riemann::Dash::Static, :root => store[:public]
   end
 
+  def setup_storage_backend
+    uri = URI.parse(ws_config_file)
+    backend = case uri.scheme
+            when "s3"
+              Riemann::Dash::BrowserConfig::S3.new(uri.host, uri.path.sub(/^\//, ''), store[:s3_config])
+            when nil, "file"
+              Riemann::Dash::BrowserConfig::File.new(uri.path)
+            else
+              raise Exception.new "Unknown backend for #{ws_config_file}"
+            end
+    Riemann::Dash::BrowserConfig.backend = backend
+  end
+
   # Load controllers.
   def load_controllers_from(dir)
     sorted_controller_list(dir).each do |r|

lib/riemann/dash/controller/index.rb

@@ -5,16 +5,16 @@ class Riemann::Dash::App
 
   get '/config', :provides => 'json' do
     content_type "application/json"
-    Riemann::Dash::BrowserConfig.read config
+    Riemann::Dash::BrowserConfig.read
   end
 
   post '/config' do
     # Read update
     request.body.rewind
-    Riemann::Dash::BrowserConfig.update config, request.body.read
+    Riemann::Dash::BrowserConfig.update request.body.read
 
     # Return current config
     content_type "application/json"
-    Riemann::Dash::BrowserConfig.read config
+    Riemann::Dash::BrowserConfig.read
   end
 end

riemann-dash.gemspec

@@ -21,6 +21,7 @@ Gem::Specification.new do |gem|
   gem.add_dependency 'sass', '>= 3.1.14'
   gem.add_dependency 'thin', '>= 1.3.1'
   gem.add_dependency 'multi_json', '1.3.6'
+  gem.add_dependency 'fog'
   gem.files         = `git ls-files`.split($/)
   gem.executables   = gem.files.grep(%r{^bin/}).map{ |f| File.basename(f) }
   gem.test_files    = gem.files.grep(%r{^(test|spec|features)/})