Rewrite

Apply the safe part of the migration without guessing through the risky part.

rewrite takes the analyzed findings and applies the changes the rule pack explicitly marks as deterministic and safe, plus any assisted scaffolds the pack declares as reviewable output. It writes a new artifact and a rewrite report.

Back to site Supporting source

What rewrite will do

  • rename a property when the mapping is explicit
  • replace a component type when Apache guidance is direct and mechanically safe
  • scaffold target properties when a migration is reviewable but still not fully automatic
  • keep untouched parts of the flow intact

What rewrite will not do

  • invent replacements for removed processors
  • guess through custom JAR or architecture changes
  • recreate secrets NiFi never exported
nifi-flow-upgrade rewrite \
  --plan ./out/migration-report.json \
  --output-dir ./out

What to expect

Rewrite may apply zero operations and still be useful. That simply means the advisor found migration work, but none of it was safe or scaffoldable to automate. The original source is not silently mutated; you get a reviewed output and a rewrite report.