File-logger

File-logger is a library which implements log file rotation: it maintains max X log files of max size Y, so that you always have latest logs from the device persisted on the filesystem. By default there are max 10 files, prefixed with log_, each of max size 4000 bytes.

See mos.yml for the possible options. At least you'd have to enable this lib in your app's mos.yml, like this:

Note that for the message to get to file logger it needs to be allowed by debug.level and debug.event_level. File logger then examines file_logger.level and file_logger.include to make final determination.

file_logger.include is a list of substrings to match, so a value of mg_rpc.c,Tick,Tock will match lines containing any of "Tick, "Tock" or "mg_rpc.c".

libs:
  - origin: https://github.com/mongoose-os-libs/file-logger

config_schema:
  - ["file_logger.enable", true]

Fetching logs

See this script.