1 unstable release
0.1.0 | Aug 9, 2019 |
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#623 in Configuration
16KB
323 lines
SSCCPP, the Simple Switch Cases Configuration PreProcessor
This small utility makes it easy to have a single file that can be adapted to different cases. Typical use is to manage dotfiles, by allowing to have only one git branch which is then preprocessed before being used as an actual configuration file.
It is written in Rust and provides a library as well as two binaries: ssccpp
and ssccpp-batch
. ssccpp
processes a single file while ssccpp-batch
process all files in a directory, copying its structure to an other one.
Concept
ssccpp
works on a file where some lines have been turned into switch statements.
These switch statements are recognized by looking for a delimiter (by default >>>>>>>>
ie. 8 times the '>' character).
A switch block is composed of, in order:
- One or more "specfic" case(s):
>>>>>>>> ident1, ident2, ...
- One "otherwise" case:
>>>>>>>> *
- And ending delimiter:
>>>>>>>>
When reaching such a block, ssccpp will check, for each specific case if one of the ident
matches the searched ident (by default the hostname), and if yes, will emit the text that follows.
When reaching the otherwise block, it will emit the text that follows if none of the specific statements before were entered. Finally, when reaching the ending delimiter, it will print all following text, until a new block is encountered.
Examples
First example
This line will be displayed everywhere.
>>>>>>>> foo, bar
This line will be displayed on foo and bar only.
>>>>>>>> ga, bu, zo
This line will be displayed on ga, bu and zo, but not foo or bar.
>>>>>>>> foo, zo
This line will be displayed on foo and zo.
>>>>>>>> *
This line will be displayed on anything that is not foo, bar, ga, bu or zo.
>>>>>>>>
This line will be displayed everywhere.
Configuration files example
In this example, the user has a dotfiles
directory that mimics the structure of their /home/user
directory:
dotfiles/
├── scripts/
│ └── wallpaper.sh
└── .xinitrc
The file content is as follow:
wallpaper.sh
>>>>>>>> laptop
feh --bg-scale 'Images/WallpaperLaptop.png'
>>>>>>>> *
feh --bg-scale 'Images/DefaultWallpaper.png'
.xinitrc
>>>>>>>> desktop
xrandr --dpi 166
>>>>>>>> laptop
xrandr --dpi 96
>>>>>>>>
exec i3
Upon executing ssccpp-batch dotfiles/ /home/user --ident laptop
the files will be placed with the same structure in their home directory and become:
wallpaper.sh
feh --bg-scale 'Images/WallpaperLaptop.png'
.xinitrc
xrandr --dpi 96
exec i3
and upon executing ssccpp-batch dotfiles/ /home/user --ident desktop
the files will become:
wallpaper.sh
feh --bg-scale 'Images/DefaultWallpaper.png'
.xinitrc
xrandr --dpi 166
exec i3
Dependencies
~2.7–4MB
~61K SLoC