bash script for shortening urls with git.io

gitio

#!/usr/bin/env bash
# Author: Nathan Farrar <nfarrar@crunk.io>
# Website: https://crunk.io
# Description: Command-line git.io shortner script, in bash.
# 
#/ Usage: gitio [options] <url>
#/ Shortens github URLs using git.io. The generated URL is automatically
#/ copied to the clipboard (requires xclip on linux platforms).
#/   -c <code>  Specify an optional code to be used as a 'vanity' URL.
#/   -v         Display verbose messages.
#/   -h         Display this message & exit.


# Required to trim whitespace when parsing response.
shopt -s extglob

# The url for the git.io api service.
api_url="http://git.io"

# Output wrappers.
msg() { printf '\x1b[90m%s\x1b[0m\n' "$1" >&2; }
dbg() { [[ $dbg -eq 1 ]] && printf '\x1b[35mDEBUG:\t%s\x1b[0m\n' "$1" >&2; }
err() { printf '\n\x1b[31mERROR:\t%s\x1b[0m\n' "$1" >&2; }

# Display the usage message.
usage() {
  while IFS='\n' read -r line ; do
    msg "$line"
  done < <(grep '^#/' <"$0" | cut -c4-)
}

# If no arguments were provided, display the usage message and exit.
[[ $# -eq 0 ]] && { usage; exit 0; }; 

# Parse options using getopts.
# The leading ':' tells getopts to suppress error messages (they're handled
# by the getopts loop. The ':' after 'c' tells getopts that 'c' has a required
# argument.
while getopts ":hdc:" option; do
  case "${option}" in
    h) usage;exit 0;;
    d) dbg=1;;
    c) code=$OPTARG;;
   \?) usage; err "Unknown option: -$OPTARG" >&2; exit 1;;
    :) usage; err "Missing option argument for -$OPTARG" >&2; exit 1;;
    *) usage; err "Unimplemented option: -$OPTARG" >&2; exit 1;;
  esac
done

# Strip out the processed options, leaving the remaining command line
# arguments. The only argument left *should* be the URL to shorten.
shift "$((OPTIND - 1))"
[[ $# -ne 1 ]] && { usage; err "URL not provided."; exit 1; }

url="$1"
cmd="curl -s -i $api_url -F url=$url ${code:+-F code=$code}"

dbg "api_url=$api_url"
dbg "url=$url"
dbg "code=$code"
dbg "cmd=$cmd"

# If debugging output is enabled, insert an extra newline before it.
[[ $dbg -eq 1 ]] && printf "\n" >&2

# Execute the curl command, and parse the response values as key:value pairs.
# The output from the command is tee'd to stderr, so that we can see the
# response and still capture the output.
while IFS=':' read key value; do
  value=${value##+([[:space:]])}; value=${value%%+([[:space:]])}

  case "$key" in
      Status) status="$value";;
    Location) location="$value";;
       HTTP*) read PROTO STATUS MSG <<< "$key{$value:+:$value}";;
  esac
done < <($cmd | tee >(cat >&2) )

# If debugging output is enabled, insert an extra newline before it.
[[ $dbg -eq 1 ]] && printf "\n" >&2
dbg "status=$status"
dbg "location=$location"

printf "The URL $url has been shortened to $location.\n"

# Copy the location to the clipboard.
if [[ "$OSTYPE" == "darwin"* ]]; then
  printf "$location" | pbcopy
  dbg "copied $location to clipboard"
elif [[ $OSTYPE == 'linux-gnu' ]] && [[ -x $(command -v xclip) ]]; then
  printf "$location" | xclip -selection clipboard
  dbg "copied $location to clipboard"
elif [[ $OSTYPE == "cygwin" ]]; then
  printf "$location" | /dev/clipboard
  dbg "copied $location to clipboard"
fi