Merge pull request #234 from edx/max/block-on-validate

Verify that ES is configured properly before starting

config/unicorn.rb

 require 'tmpdir'
+
+# Load app.rb to get all dependencies.
+require 'app.rb'
+
+# Make sure elasticsearch is configured correctly
+UnicornHelpers.exit_on_invalid_index
+
 worker_processes Integer(ENV['WORKER_PROCESSES'] || 4)
 timeout 25
 preload_app true

config/unicorn_tcp.rb

 require 'tmpdir'
+
+# Load app.rb to get all dependencies.
+require 'app.rb'
+
+# Make sure elasticsearch is configured correctly
+UnicornHelpers.exit_on_invalid_index
+
 worker_processes Integer(ENV['WORKER_PROCESSES'] || 4)
 timeout 25
 preload_app true

lib/unicorn_helpers.rb

+module UnicornHelpers
+
+  # Make sure elasticsearch is configured correctly
+  def self.exit_on_invalid_index
+    begin
+      TaskHelpers::ElasticsearchHelper.validate_index(Content::ES_INDEX_NAME)
+    rescue => e
+      # Magic exit code expected by forum-supervisor.sh for when
+      # rake search:validate_index fails
+      STDERR.puts "ERROR: ElasticSearch configuration validation failed. "\
+           "\"rake search:validate_index\" failed with the following message: #{e.message}"
+      exit(101)
+    end
+  end
+
+end

spec/lib/unicorn_helpers_spec.rb

+require 'spec_helper'
+require 'elasticsearch'
+
+describe UnicornHelpers do
+  include_context 'search_enabled'
+
+  context("#exit_on_invalid_index") do
+    subject { UnicornHelpers.exit_on_invalid_index }
+
+    it "doesn't exit when index is valid" do
+      # code 101 is special code recongnized by forum-supervisor.sh
+      lambda{subject}.should_not exit_with_code(101)
+    end
+
+    it "exits when index is invalid" do
+      TaskHelpers::ElasticsearchHelper.delete_index(Content::ES_INDEX_NAME)
+      # code 101 is special code recongnized by forum-supervisor.sh
+      lambda{subject}.should exit_with_code(101)
+    end
+
+  end
+end

spec/support/matchers.rb

@@ -5,3 +5,26 @@ RSpec::Matchers.define :be_an_empty_response do
     actual.body == '{}'
   end
 end
+
+RSpec::Matchers.define :exit_with_code do |exp_code|
+  actual = nil
+
+  match do |block|
+    begin
+      block.call
+    rescue SystemExit => e
+      actual = e.status
+    end
+    actual and actual == exp_code
+  end
+  failure_message_for_should do |block|
+    "expected block to call exit(#{exp_code}) but exit" +
+        (actual.nil? ? " not called" : "(#{actual}) was called")
+  end
+  failure_message_for_should_not do |block|
+    "expected block not to call exit(#{exp_code})"
+  end
+  description do
+    "expect block to call exit(#{exp_code})"
+  end
+end