Template Syntax

The *-syntax options can be used to customize the plugin output.

Here is a list of available syntax options which are common for all check plugins.

Templates may contain text, conditionals and macros.

Macros

Macros can be used to access attributes of the current check. The form is the same as used in the config file (snclient.ini)

The macro syntax is explained in detail the macro section of the configuration page.

Supported macro variants:

• ${macroname}
• %(macroname)
• all variants of $ / % and {} / () are interchangeable

Example:

check_memory 'detail-syntax=%(type) = %(used)/%(size) (%(used_pct)%)'

All macros can also make use of macro operators.

For example, the default output applies floating point format to make the output more readable:

check_memory 'detail-syntax=%(type) = %(used)/%(size) (%(used_pct | fmt=%.1f)%)'

The list of available macros for each check is available in the help page of each check. Another way is to run the check with -vv verbose mode, which prints the list details as well.

Conditionals

Conditionals can be used to support different output based on expressions.

The basic syntax is:

{{ IF <expression> }}...{{ ELSIF <expression> }}...{{ ELSE }}...{{ END }}

Example:

check_service \
    service=sshd \
    detail-syntax='%(name) - {{ IF state == running }}memory: %(rss:h)B cpu: %(cpu:fmt=%.1f)% - age: %(created:age:duration){{ else }}service is $(state){{ end }}' \
    show-all

That way, in case of errors a useful message can be displayed and performance details otherwise.

For better readability, here is the template again in multiple lines:

%(name) -
{{ IF state == running }}
    memory: %(rss:h)B cpu: %(cpu:fmt=%.1f)% - age: %(created:age:duration)
{{ else }}
    service is $(state)
{{ end }}