Regex to only pull files with a specific name and date for the day

Grafana Alloy
1

I am looking to see if there is a way to use regex and local.file_match to only send spefic logs to loki?

Basically, i have a folder that has many files in it of logs. each log would be DataFeeds_todays date.log

So, it would look something like this DataFeed_2025-05-16.log

There would be one for everyday but i am only interested in the current day’s logs. so tomorrow log I would be interested in tomorrow which would be called. DataFeed_2025-05-17.log and so forth. This this possible to do or am I SOL?

Something like this:

local.file_match "local" {
    path_targets = [{__path__ ="D:/ServiceLogs/DataFeedsService/^DataFeeds_[0-9]*.log"},]
}
2

I am not sure you can do that. your options might be

  1. generate the alloy config file daily through an external process that will plugin today’s file name in the config file (oogly)
  2. have a today folder and point to that (cleaner but you might not have control of where files get dumped to) D:/ServiceLogs/DataFeedsService/Today/DataFeed_2025-05-16.log
  3. archive older files to an archive folder D:/ServiceLogs/DataFeedsService/Archives only leaving today’s file untouched in root folder D:/ServiceLogs/DataFeedsService/DataFeed_2025-05-16.log
3

Thats a little upsetting. Ya my next option was to basically have the person who building this data to change it around a bit.

  1. change the current file to be named: DataFeed.log and the older files to be labeled with the date stamp.
  2. do as you suggested and have the old files archived out so only the current days file is in the folder
  3. just use a different system to accomplish this task

Thanks for the help and info.

1 Like
4

i was also trying to figure out is the argument older than ignore_older_than would work.

But whatever syntex i out in there doesn’t seem to work. Like 1d, 24hr, 24h, 5m, 5min etc.

local.file_match "local" {
    path_targets = [{__path__ ="D:/ServiceLogs/DataFeedsService/*.log"},
    ignore_older_than = "1d"]
}
1 Like
5

if you go with DataFeed.log I don’t think you will need archives

6

ignore_older_than = "24h"