Description
Nano is a simple terminal-based text editor. Though not as powerful as Emacs or Vim, it is easy to learn and use. A lot of developers prefer this editor as it’s very simple to use and pretty useful when you only want to edit a single file quickly on your server.
One of those files that you need to change often in this kind of editor are configuration file, like yaml files. Nano offers syntax highlighting for many file types, however not for yaml files. If you want to highlight this kind of files as well, you will need to follow an extra step.
1 List available Nano Syntax Highlight Files [root@ansible]:[~]# ls /usr/share/nano/
asm.nanorc changelog.nanorc css.nanorc elisp.nanorc go.nanorc html.nanorc json.nanorc man.nanorc nanohelp.nanorc objc.nanorc perl.nanorc postgresql.nanorc ruby.nanorc spec.nanorc tex.nanorc
autoconf.nanorc cmake.nanorc debian.nanorc fortran.nanorc groff.nanorc java.nanorc lua.nanorc mgp.nanorc nanorc.nanorc ocaml.nanorc php.nanorc pov.nanorc rust.nanorc tcl.nanorc xml.nanorc
awk.nanorc c.nanorc default.nanorc gentoo.nanorc guile.nanorc javascript.nanorc makefile.nanorc mutt.nanorc nftables.nanorc patch.nanorc po.nanorc python.nanorc sh.nanorc texinfo.nanorc
[root@ansible]:[~]#
2 Create YAML Nano Syntax Highlighting File In order to provide syntax highlighting to your file, if the default file doesn’t exist, you need to create the syntax highlighting file for this language. This file is the yaml.nanorc file and you need to create it in the mentioned directory. Run nano to create the file:nano /usr/share/nano/yaml.nanorc
and paste the following content:# Supports `YAML` files
syntax "YAML" "\.ya?ml$"
header "^(---|===)" "%YAML"
## Keys
color magenta "^\s*[\$A-Za-z0-9_-]+\:"
color brightmagenta "^\s*@[\$A-Za-z0-9_-]+\:"
## Values
color white ":\s.+$"
## Booleans
icolor brightcyan " (y|yes|n|no|true|false|on|off)$"
## Numbers
color brightred " [[:digit:]]+(\.[[:digit:]]+)?"
## Arrays
color red "\[" "\]" ":\s+[|>]" "^\s*- "
## Reserved
color green "(^| )!!(binary|bool|float|int|map|null|omap|seq|set|str) "
## Comments
color brightwhite "#.*$"
## Errors
color ,red ":\w.+$"
color ,red ":'.+$"
color ,red ":".+$"
color ,red "\s+$"
## Non closed quote
color ,red "['\"][^['\"]]*$"
## Closed quotes
color yellow "['\"].*['\"]"
## Equal sign
color brightgreen ":( |$)"
Visit the official repository of Nano Highlight , a spiffy collection of nano syntax highlighting files for more information and languages available for nano. This file will be automatically added into nano and will highlight yaml files. Save changes and proceed with the last step.
3 Create Test Yaml File to see results As final step, you need to test wheter the highlight works or not. Proceed to create a test file with nano and write some YAML on it, for example:- hosts: updates
gather_facts: False
tasks:
- name: Check Dist Version
shell: cat /etc/os-release
register: response
- debug: msg=''
Save the file, edit it again and you will now see the YAML code highlighted.