Groovy scripts to painless

[living_jordi]

I wrote this script using groovy language (datediff.groovy):

(doc[secondDateField].date.millis - doc[firstDateField].date.millis) / 3600000

It works fine. Nevertheless, I'm intended to move these script to painless (datediff.painless). Nevertheless, I'm getting compilation error on straup:

[esn1] failed to load/compile script [datediff]: {
   "type" : "script_exception",
   "reason" : "compile error",
   "caused_by" : {
     "type" : "illegal_argument_exception",
     "reason" : "Variable [secondDateField] is not defined."
   },
   "script_stack" : [
     "(doc[secondDateField].date.mil ...",
     "     ^---- HERE"
   ],
   "script" : "(doc[secondDateField].date.millis - doc[firstDateField].date.millis) / 3600000",
   "lang" : "painless"
}

It's telling me secondDateField is not defined. Could you help me in order to get it?

[Mark_Harwood]

Try quotes around field names as per https://www.elastic.co/guide/en/elasticsearch/reference/master/modules-scripting-painless.html#_accessing_doc_values_from_painless

[living_jordi]

seconfDateField is not a literal is a variable that acts as a script parameter.

The issue is how to get the content of this parameter in order to index the document.

[Mark_Harwood]

params.secondDateField