Customize neo4j log file to JSON
From the Neo4j Documentation: Section 4.2 File Locations: 4.2.1 Where to find important files; sub-bullet [3] Explains that to view the neo4j.log file one should use journalctl --unit=neo4j to query systemd.
According to the journalctl manpage, there is an option to format your output with many possible formats, namely: journalctl --output=json
So your solution might be something like:
journalctl --output=json --unit=neo4j
Orjournalctl --output=json-pretty --unit=neo4j