Initial commit

lib/varnish/lib/cartodb-varnish.rb

@@ -0,0 +1,77 @@
+require "net/telnet"
+require_relative '../../carto/http/client'
+
+module CartoDB
+  class Varnish
+    def purge(what)
+      ActiveSupport::Notifications.instrument('purge.varnish', what: what) do |payload|
+        conf = Cartodb::config[:varnish_management]
+        if conf['http_port']
+          request = http_client.request(
+            "http://#{conf['host']}:#{conf['http_port']}/batch", method: :purge, headers: {"Invalidation-Match" => what}).run
+          return request.code
+        else
+          return send_command("#{purge_command} obj.http.X-Cache-Channel ~ #{what}") do |result|
+            payload[:result] = result
+            result
+          end
+        end
+      end
+    end
+
+    def purge_surrogate_key(key)
+      ActiveSupport::Notifications.instrument('purge.varnish', what: key) do |payload|
+        conf = Cartodb::config[:varnish_management]
+        if conf['http_port']
+          request = http_client.request(
+            "http://#{conf['host']}:#{conf['http_port']}/key", method: :purge, headers: {"Invalidation-Match" => key}).run
+          return request.code
+        else
+          return send_command("#{purge_command} obj.http.Surrogate-Key ~ #{key}") do |result|
+            payload[:result] = result
+            result
+          end
+        end
+      end
+    end
+
+    def send_command(command)
+      retries = 0
+      response = nil
+      conf = Cartodb::config[:varnish_management]
+      begin
+        retries += 1
+        connection = Net::Telnet.new(
+          'Host' => conf["host"],
+          'Port' => conf["port"],
+          'Timeout' => conf["timeout"] || 5)
+
+        connection.cmd('String' => command, 'Match' => /\n\n/) {|r| response = r.split("\n").first.strip}
+        connection.close if connection.respond_to?(:close)
+      rescue Exception => e
+        if retries < conf["retries"]
+          retry
+        else
+          if Cartodb::config[:varnish_management]["critical"] == true
+            raise "Varnish error while trying to connect to #{conf["host"]}:#{conf["port"]} #{e}"
+          end
+        end
+      end
+      response
+    end
+
+    private
+
+    def purge_command
+      Cartodb::config[:varnish_management]["purge_command"]
+    end #purge_command
+
+    def url_purge_command
+      Cartodb::config[:varnish_management]["url_purge_command"]
+    end #purge_command
+
+    def http_client
+      @http_client ||= Carto::Http::Client.get('varnish')
+    end
+  end # Varnish
+end # CartoDB