How to output only one User-Agent?

[riku22]

Hello.

I'm trying to log only one from the User-Agent header. I wrote the following template.

format formatted "{{index request>headers>User-Agent 0}}"

However, this does not work well, and the character string specified in the format as shown below is output as it is.

{{index request>headers>User-Agent 0}}

Is it difficult to do this?

The environment is as follows.

• Ubuntu 20.04.1 LTS
• Caddy v2.2.1 h1:Q62GWHMtztnvyRU+KPOpw6fNfeCD3SkwH7SfT1Tgt2c=
• github.com/caddyserver/format-encoder v0.0.0-20200619105626-addf3285dafc h1:ql2pYXx8r7+8c48XmOKb1Ui6FmKpEboX3yThQOJ6DwY=

Best regards.

[mohammed90]

The template isn't a Go template, so the usage of double braces and the function index isn't correct. The syntax of the template is defined by the backing library github.com/buger/jsonparser. For your use-case, you need: format formatted "{request>headers>User-Agent>[0]}".

This is a shortcoming in the documentation of this module. I'll address it in the README shortly.