Module: OllamaChat::Utils::LogRotation

Defined in:
lib/ollama_chat/utils/log_rotation.rb

Overview

Truncates a log file in-place, keeping only the last N lines.

Uses File::Tail#backward to seek to the start of the tail portion without loading the entire file into memory. The file is rewritten in-place (same inode) so that tailing processes (e.g. ollama_chat_log) can continue following the file.

Class Method Summary collapse

Class Method Details

.truncate_tail(path, keep_lines:) ⇒ Object

Truncates a log file in-place, keeping only the last keep_lines.

If the file has fewer lines than keep_lines, it is left untouched. The operation is a no-op if the file does not exist.

Parameters:

  • path (String, Pathname) —

    the log file to truncate

  • keep_lines (Integer) —

    the number of lines to retain



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# File 'lib/ollama_chat/utils/log_rotation.rb', line 17

def self.truncate_tail(path, keep_lines:)
  return unless File.exist?(path)
  File.open(path, 'r+') do |f|
    f.extend(File::Tail)
    f.backward(keep_lines)
    return if f.pos.zero?
    tail = f.read
    f.rewind
    f.write(tail)
    f.truncate(f.pos)
  end
end