Logstash CSV String Text containing commas

Dear Logstash Community,

Need your help. I am facing an issue with Network Switch Traffic that comes in the form of CSV files. The problem is some of the fields contain commas in it e.g. a URL and the string isn't encapsulated within quotation marks.

For example URL = http://url.com/search.?aspx=feed1@x1,x2,x3

What happens is now my message is and columns are blown out and I get something like:

URL, Bytes, column 30, column 31 etc. Where column 30 and 31 is new columns added by the CSV filter.

Below is my logstash conf file:

input {
file {
	path => "/Users/wtaylor/Downloads/logstash-2.2.2/bin/sce/*.csv"
	type => "usage"
	start_position => "beginning"

filter {
csv {
	columns => [
separator => ","

output {
    stdout { codec => json_lines }

I ideally need to get length of the array if split by commas and join the extra commas one of the fields e.g. INFO_STRING

Does anyone know how to achieve this.