cascade remove mongodb's collections

mongorm.sh

#!/bin/bash
# remove mongodb's collections with command "mongn rm app*"
# Usage `mongorm <-c collections*> <-d dababase>`

E_BADARGS=85
E_NOFILE=86

DATABASE=''
COLLECTIONS=''

while getopts "c:d:h" arg
do
        case $arg in
             c)
                echo "-c $OPTARG"
                COLLECTIONS=$OPTARG
                ;;
             d)
                echo "-d $OPTARG"
                DATABASE=$OPTARG
                ;;
             h)
                 echo "mongorm <-d database> <-c collections>"
                 echo "for exp:"
                 echo "        mongorm -d bpc -c app*"
                 ;;
             ?)
                echo "unkonw argument"
        exit 1
        ;;
        esac
done

if [[ -z "$DATABASE" ]]
    # Correct number of arguments passed to script?
then
    echo 'Usage: -d database'
    echo 'please do mongorm.sh -h to get more info'
    exit $E_BADARGS
fi

if [[ -z "$COLLECTIONS" ]]
    # Correct number of arguments passed to script?
then
    echo 'Usage: -c collections'
    echo 'please do mongorm.sh -h to get more info'
    exit $E_BADARGS
fi

mongojs_rm_function=`cat << EOF
db.getCollectionNames().forEach(function(c) {
    if(c.match("$COLLECTIONS")) {
                db.getCollection(c).drop();
                    }
                  });
EOF
`
echo $mongojs_rm_function>remove.js

mongo 127.0.0.1:27017/$DATABASE remove.js
rm -rf remove.js