How can I get the message field of previous event in elasticsearch? The document ID is dynamically
{
"request" : {
"url" : "https://reiseauskunft.bahn.de/bin/stboard.exe/dn?rt=1&input=Stuttgart%20Hauptbahnhof&boardType=dep&L=vs_java3&productsFilter=111110111&start=yes&maxJourneys=20",
"method" : "get"
},
"times_retried" : 0,
"response_message" : "OK",
"name" : "test2",
"code" : 200
},
"@timestamp" : "2019-12-05T14:21:46.498Z",
"message" : "<Journey fpTime="15:14" fpDate="05.12.19" delay="+ 17" e_delay="17" newpl="15" platform="16" targetLoc="München Hbf" dirnr="8000261" prod="ICE 597#ICE" administration="80____" is_reachable="0" delayReason=" Verspätung eines vorausfahrenden Zuges" approxDelay="0"><Journey fpTime="15:16" fpDate="05.12.19" delay="+ 15" e_delay="15" platform="3" targetLoc="Singen(Hohentwiel)" dirnr="8000073" prod="RE 52389#RE" dir="Singen(Hohentwiel)" administration="NZ____" is_reachable="0" delayReason=" Verspätung aus vorheriger Fahrt" approxDelay="0"><Journey fpTime="15:16" fpDate="05.12.19" delay="+ 15" e_delay="15" platform="3"
"tags" : [
"_elasticsearch_lookup_failure"
]
}