I want to output the kubernetes log to a file. but, I could only output it as json data. I want to output only "message" part to file.
How do I choose "message" to print? Which filter should I choose?
<match output_tag>
@type rewrite_tag_filter
<rule>
key $['kubernetes']['labels']['app']
pattern ^(.+)$
tag app.$1
</rule>
</match>
<match app.tom1>
@type file
path /logs/tom1
</match>
Execute result:--->
2019-10-30T00:46:05+09:00 app.tom1 {
..
"message": "2019-10-29 15:46:05,253 DEBUG [org.springframework.web.servlet.DispatcherServlet] Successfully completed request",
"kubernetes": {
"labels": {
"app": "tom1",
..
}
Desired result: --->
2019-10-29 15:46:05,253 DEBUG [org.springframework.web.servlet.DispatcherServlet] Successfully completed request
Thank!
Try the single_value <formater> plugin: https://docs.fluentd.org/formatter/single_value
<match app.tom1>
@type file
path /logs/tom1
<format>
@type single_value
message_key message
</format>
</match>