Golang regexp
package uses the RE2 syntax.
Example CLI usage (from honeytail root)
honeytail -p regex -k $HONEYTAIL_WRITEKEY \
-f some/path/system.log \
--dataset 'MY_TEST_DATASET' \
--backfill \
--regex.line_regex="(?P<time>\d{2}:\d{2}:\d{2}) (?P<field1>\w+)" \
--regex.line_regex="(?P<foo>\w+)" \
--regex.timefield="time" \
--regex.time_format="%H:%M:%S"