gistfile1.txt

input {

  file {
    type => "couchpotato"
    path => [ "/logs/couchpotato/CouchPotato.log" ]
    start_position => "beginning"
    sincedb_path => "/dev/null"
  }

}

filter {
  # Get rid of any color codes
  # NOT WORKING
  #mutate {
  #  gsub => [ "message", "\\e\[0m", ""]
  #}

  grok {
    match => [ "message", "%{MONTHNUM}-%{MONTHDAY} %{TIME} %{LOGLEVEL} \\e\[0m\[%{DATA:module}\] %{GREEDYDATA:couch_message}\\e\[0m" ]
  }
}

output {
  stdout { codec => rubydebug }
}

Full config (updated to catch space or not):

input { stdin {} }

filter {
  # Get rid of any color codes
  mutate {
    gsub => [ "message", "\\e\[0m", ""]
  }
  grok {
    pattern => [ "%{MONTHNUM}-%{MONTHDAY} %{TIME} %{LOGLEVEL} \[(?:%{SPACE})%{NOTSPACE:module}\] %{GREEDYDATA:couch_message}" ]
  }
}

output { stdout { codec => rubydebug } }