How to wirte Caddyfile

How should I write the Caddyfile if I want to log only the /myipback path?
I tried using GPT to answer my question, but it gave me incorrect answers

here is the GPT answer
yourwebsite.com {
route /myipback* {
log {
output file /tmp/myipback.log
format console
}
respond “Logging for /myipback” 200
}
}

GPT’s answer doesn’t work because you can only use handler directives inside a route.

Try with log_skip (Caddyfile directive) — Caddy Documentation.

http:// {
  log
  @nologs not path /myipback*
  log_skip @nologs
}

i try to copy the code to my Caddyfile, it shows

Error: adapting config using caddyfile: getting matcher module ‘/myipback*’: module not registered: http.matchers./myipback*, at Caddyfile:6
Error: caddy process exited with error: exit status 1

Whups, it should read @nologs not path /myipback* (I forgot path). Edited to fix.

thanks, How should I write the Caddyfile if I only want to log the visitor’s IP and http_user_agent?

Check out the log documentation. It allows for per-field filtering, so you could simply remove all the fields you don’t care about:

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I’m just a computer beginner and find it a bit difficult to understand technical documents. I still tried asking GPT, but the answers I got were still wrong. I would greatly appreciate it if you could provide the complete Caddyfile content.
Below is the incorrect content I got from asking GPT.

:88 {
log {
output file /root/myipback.log
format single_field {
field header.User-Agent
}
}
@nologs not path /myipback*
log_skip @nologs
root * /root/html/
file_server {
index index.html
}
}

When I run Caddy, it reports the following error.
Error: adapting config using caddyfile: parsing caddyfile tokens for ‘log’: getting module named ‘caddy.logging.encoders.single_field’: module not registered: caddy.logging.encoders.single_field, at Caddyfile:7

Check out the examples:

Delete the User-Agent request header from the logs:

example.com {
	log {
		format filter {
			request>headers>User-Agent delete
		}
	}
}

https://caddyserver.com/docs/caddyfile/directives/log#examples

I don’t know the full list of fields off the top of my head, but you’d just have to add more <field> delete entries inside the format filter block until you’ve gotten rid of all of them except for the visitor’s IP/user agent.

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it seems not working
i try to delete some fields, but it still gets logged in my log

here is my Caddyfile
:88 {
log {
output file /root/asusipback.log
format filter {
request>request delete
request>proto delete
request>method delete
request>host delete
level delete
ts delete
logger delete
msg delete
bytes_read delete
user_id delete
duration delete
size delete
status delete
resp_headers delete
request>headers>User-Agent query
}
}
@nologs not path /myipback*
log_skip @nologs
root * /root/html/
file_server {
index index.html
}

and here is my log

{“level”:“info”,“ts”:1718097693.5529747,“logger”:“http.log.access.log0”,“msg”:“handled request”,“request”:{“remote_ip”:“xxx.xxx.xxx.xxx”,“remote_port”:“41252”,“client_ip”:“149.xxx.xxx.xxx”,“uri”:“/myipback”,“headers”:{“Connection”:[“Keep-Alive”],“User-Agent”:[“hello”],“Accept”:[“/”]}}}

Many fields are built-in and can’t be removed.

You might want to consider using GitHub - caddyserver/transform-encoder: Log encoder module for custom log formats instead of filter which will let you have more control over the output.

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