如何跟踪日志文件并在输出到不同的文件之前在每一行添加command: word？

#!/bin/bash

# 输入日志文件
input_file="input.log"

# 输出日志文件
output_file="output.log"

# 使用sed命令在每一行前添加"command: word"
sed 's/^/command: word /' "$input_file" > "$output_file"

# input_log.py

# 输入日志文件
input_file = "input.log"

# 输出日志文件
output_file = "output.log"

# 打开输入文件和输出文件
with open(input_file, 'r') as infile, open(output_file, 'w') as outfile:
    for line in infile:
        # 在每一行前添加"command: word"
        outfile.write("command: word " + line)

input {
  file {
    path => "/path/to/input.log"
    start_position => "beginning"
  }
}

filter {
  mutate {
    add_field => { "command" => "word" }
  }
}

output {
  file {
    path => "/path/to/output.log"
  }
}

logstash -f logstash.conf