Track Twitter Unfollowers

twitter-changes.sh

#!/bin/sh

#
# Track Twitter Unfollowers
#
# Run script daily using crontab and TextMate as follows:
# $ mate -w | crontab
# …paste `* */6 * * * /path/to/twitter-changes.sh`
#
# Adapted to Mac OS X from original script by Samuel Alba:
# http://shad.cc/how-to-know-all-of-your-unfollowers-on-twitte
#
# Mac OS X `readlink -f` workaround from Stack Overflow:
# http://stackoverflow.com/questions/1055671/1116890#1116890
readlink2() {
    TARGET_FILE=$1

    cd `dirname $TARGET_FILE`
    TARGET_FILE=`basename $TARGET_FILE`

    # Iterate down a (possible) chain of symlinks
    while [ -L "$TARGET_FILE" ]
    do
        TARGET_FILE=`readlink $TARGET_FILE`
        cd `dirname $TARGET_FILE`
        TARGET_FILE=`basename $TARGET_FILE`
    done

    # Compute the canonicalized name by finding the physical path
    # for the directory we're in and appending the target file.
    PHYS_DIR=`pwd -P`
    RESULT=$PHYS_DIR/$TARGET_FILE
    echo $RESULT
}


# Config
SCREEN_NAME="gasi"
EMAIL="daniel@gasienica.ch"


(
cd $(dirname $(readlink2 $0))
mv latest.log previous.log
curl -s -X GET "http://api.twitter.com/1/statuses/followers.xml?screen_name=${SCREEN_NAME}" | grep -E '^  <(screen_name|name)>' > latest.log
data=$(diff previous.log latest.log)
if [ ! -z "$data" ] ; then
    # Removed from address because of Mac OS X error message:
    # mail: illegal option -- a
    echo "$data" | mail -s "[Twitter] Today’s Changes" $EMAIL
fi
)