Split function return a list，How do I get the length of this list?

[Drewolf]

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1. Describe your incident:
the rule function which name split, return a list，How do I get the length of this list. I want to use this length as a condition.
the length function returns the length of the string, not the list.

3. What steps have you already taken to try and solve the problem?
this is my rule:

rule "test"
when
    true
then
    let content = split("|",to_string($message.log));
   let len= length(content) 
end

4. How can the community help?
Give me an example of calculating the length of a list

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[patrickmann]

There is a long-standing request for length():

Processing function `length` of field

We now have Length(string) but still nothing for list. Add a comment there to raise visibility - thx.

There is a limited ability to use methods of the Java data types, but this only works for getters:
https://go2docs.graylog.org/5-0/making_sense_of_your_log_data/functions.html

[Drewolf]

thank you, it is too bad