Create a gmail river using imapriver in elasticsearch

curl -XPUT localhost:9200/_river/gmailriver/_meta -d 
"{"type":"imap",
   "mail.store.protocol":"imap",
   "mail.imap.host":"imap.googlemail.com",
   "mail.imap.port":993,
   "mail.imap.ssl.enable":true,
   "mail.imap.connectionpoolsize":"3",
   "mail.debug":"true",
   "mail.imap.timeout":10000,
   "user":"xxxx@gmail.com",
   "password":"xxxx$",
   "schedule":null,
   "interval":"60s",
   "threads":5,
   "folderpattern":"^INBOX$",
   "bulk_size":100,
   "max_bulk_requests":"2",
   "bulk_flush_interval":"5s",
   "mail_index_name":"gmailriveridx",
   "mail_type_name":"mail",
   "with_striptags_from_textcontent":true,
   "with_attachments":false,
   "with_text_content":true,
   "with_flag_sync":true,
   "index_settings" : null,
   "type_mapping" : null
}"

Maven Dependencies for rserve and rengine

<dependency>
  <groupId>org.rosuda.REngine</groupId>
  <artifactId>Rserve</artifactId>
  <version>1.8.1</version>
</dependency>

<dependency> 
  <groupId>org.rosuda.REngine</groupId>
  <artifactId>REngine</artifactId>
  <version>2.1.0</version>
</dependency>