question Why is there an error on the colon in ${attribute:find...? in Support Questions

Why is there an error on the colon in ${attribute:find...?

Wpq — Fri, 23 Jun 2023 18:19:19 GMT

I want to use RouteOnAttribute to filter on a regex. To do so, I added two attributes in the Properties:

Property	Value
private	${ip:find('^(10\|127\|169\.254\|172\.1[6-9]\|172\.2[0-9]\|172\.3[0-1]\|192\.168)\.')}
public	${ip:find('^([0-9]\|[1-9][0-9]\|1[0-9]{2}\|2[0-4][0-9]\|25[0-5])(?<!172\.(16\|17\|18\|19\|20\|21\|22\|23\|24\|25\|26\|27\|28\|29\|30\|31))(?<!127)(?<!^10)(?<!^0)\.([0-9]\|[1-9][0-9]\|1[0-9]{2}\|2[0-4][0-9]\|25[0-5])(?<!192\.168)(?<!172\.(16\|17\|18\|19\|20\|21\|22\|23\|24\|25\|26\|27\|28\|29\|30\|31))\.([0-9]\|[1-9][0-9]\|1[0-9]{2}\|2[0-4][0-9]\|25[0-5])\.([0-9]\|[1-9][0-9]\|1[0-9]{2}\|2[0-4][0-9]\|25[0-5])$')}

This processor shows two errors, both the same: `Unexpected token ':' at line 1 column 4`

Why is this an error?

Re: Why is there an error on the colon in ${attribute:find...?

joseomjr — Sun, 25 Jun 2023 01:06:30 GMT

You probably need to escape the $ which is a special character in NiFi...try adding \ or \\

Re: Why is there an error on the colon in ${attribute:find...?

cotopaul — Mon, 26 Jun 2023 06:53:52 GMT

@Wpq,

I do not think that NiFi supports the full syntax of Java regular expressions directly, like you are trying to do, especially on attributes and using NiFi's Expression Language.
What I would recommend you to try is to use NiFi's EL to replace that entire regex, something like:

${ip:startsWith('10.') or ip:startsWith('127.') or ip:startsWith('169.254.') or (ip:startsWith('172.') and ip:substring(4, 6):matches('1[6-9]|2[0-9]|3[0-1]')) or ip:startsWith('192.168.')}

The above code is not 100% correct, I am more than certain, but you can extrapolate from that example and rewrite your query somehow like that. The NiFi EL functions you should use are:
OR:
${ fileSize:lt(64):or( ${fileSize:gt(128)} )}
StartsWith:
${ filename:startsWith('fizz') }
Matches:
${ filename:matches('fizz.*txt') }
And:
${ fileSize:gt(64):and( ${fileSize:lt(128)} )}

Re: Why is there an error on the colon in ${attribute:find...?

Wpq — Mon, 26 Jun 2023 10:37:37 GMT

The issue ended up being that ip is a reserved word (a default function) so changing the name of the attribute from ip to extractedIp solved it.