Bash Command: Slugify

Slugify is a bash command that converts filenames and directories to a web friendly format.

Usage Help

Simply enter the slugify command without any arguments or with the -h option to view the usage help.

$ slugify
usage: slugify [-acdhintuv] source_file ...
   -a: remove spaces immediately adjacent to dashes
   -c: consolidate consecutive spaces into single space
   -d: replace spaces with dashes (instead of default underscores)
   -h: help
   -i: ignore case
   -n: dry run
   -t: treat existing dashes as spaces
   -u: treat existing underscores as spaces (useful with -a, -c, or -d)
   -v: verbose

Usage Examples

Note, most examples below are run in verbose mode (-v) to help illustrate the results.

Verbose mode is unnecessary in real world scenarios.

Provide escaped filenames:

$ slugify -v My\ \ file.txt
rename: My  file.txt -> my__file.txt

Alternatively provide unescaped filenames inside quotes:

$ slugify -v "My  file.txt"
rename: My  file.txt -> my__file.txt

Globs (like * and ?) work as well:

$ slugify -v *.txt
rename: My file.txt -> my_file.txt
ignore: my_web_friendly_filename.txt

Provide an unlimited number of arguments:

$ slugify -v "My first file.txt" "My second file.txt"
rename: My first file.txt -> my_first_file.txt
rename: My second file.txt -> my_second_file.txt

Directories are also supported:

$ slugify -v "My Directory"
rename: My Directory -> my_directory

Consolidate consecutive spaces into single spaces:

$ slugify -vc "My    consolidated    file.txt"
rename: My    consolidated    file.txt -> my_consolidated_file.txt

Replace spaces with dashes:

$ slugify -vd "My dashed file.txt"
rename: My dashed file.txt -> my-dashed-file.txt

The -d option replaces each space with a dash.

$ slugify -vd "My  dashed  file.txt"
rename: My  dashed  file.txt -> my--dashed--file.txt

Combine -d with -c (consolidate spaces) for a single dash between each word.

$ slugify -vdc "My  dashed  file.txt"
rename: My  dashed  file.txt -> my-dashed-file.txt

Ignore case:

$ slugify -vi "UPPER CASE FILE.txt"
rename: UPPER CASE FILE.txt -> UPPER_CASE_FILE.txt

Play it safe with a dry run:

Dry run mode does not alter the filesystem in any way.

$ slugify -n *
--- Begin dry run mode.
rename: My file.txt -> my_file.txt
ignore: web_friendly_filename.txt
--- End dry run mode.

Dry run mode also allows you to test filenames that don't exist. Great for testing!

$ slugify -n "Ghost File.txt"
--- Begin dry run mode.
not found: Ghost File.txt
rename: Ghost File.txt -> ghost_file.txt
--- End dry run mode.

Dry run mode automatically enables verbose mode so there is no need to include the -v option with -n.

Handle spaces adjacent to dashes:

In this example, without -a the dashes end up surrounded by underscores.

$ slugify -v "The Beatles - Yellow Submarine.mp3"
rename: The Beatles - Yellow Submarine.mp3 -> the_beatles_-_yellow_submarine.mp3

But with -a the adjacent spaces are removed.

$ slugify -va "The Beatles - Yellow Submarine.mp3"
rename: The Beatles - Yellow Submarine.mp3 -> the_beatles-yellow_submarine.mp3

The -a only removes spaces immediately adjacent to a dash, which may not be the desired effect (below three spaces on either side of the dash get converted into two underscores because of -a).

$ slugify -va "The Beatles   -   Yellow Submarine.mp3"
rename: The Beatles   -   Yellow Submarine.mp3 -> the_beatles__-__yellow_submarine.mp3

But -c consolidates spaces into a single space and then -a will remove the left over adjacent single spaces.

$ slugify -vac "The Beatles   -   Yellow Submarine.mp3"
rename: The Beatles - Yellow Submarine.mp3 -> the_beatles-yellow_submarine.mp3

Convert existing underscores into dashes

The -u treats underscores as spaces and -d converts spaces into dashes.

$ slugify -vud "Spaces Dashes-And_Underscores.txt"
rename: Spaces Dashes-And_Underscores.txt -> spaces-dashes-and-underscores.txt

Convert existing dashes into underscores

$ slugify -vt "Spaces Dashes-And_Underscores.txt"
rename: Spaces Dashes-And_Underscores.txt -> spaces_dashes_and_underscores.txt