User input in Bash Scripting?

Question

How can I get the user input like below which I would like to use inside my shell script to build a case condition?

./iwant2reload-worker.sh --target=cluster --cluster-name=abc
./iwant2reload-worker.sh --target=workernode --workernode-name=xyz

for example : if user issue the first command it needs to run program a and if user issue the second command it needs to run program b.

Answer 1

#!/bin/bash

while [ "$1" != "" ]; do
    PARAM=`echo $1 | awk -F= '{print $1}'`
    VALUE=`echo $1 | awk -F= '{print $2}'`
    case $PARAM in
        --target)
            TARGET=$VALUE
            ;;

        --cluster-name)
            CLUSTER_NAME=$VALUE
            ;;

        --workernode-name)
            WORKNODE_NAME=$VALUE
            ;;

        *)
            echo "ERROR: unknown parameter \"$PARAM\""
            exit 1
            ;;
    esac
    shift
done

#==========================

 if [ ${TARGET} = "cluster" ]
    then
     echo "Run programm A for ${TARGET} & ${CLUSTER_NAME}"
 fi

 if [ ${TARGET} = "workernode" ]
    then
     echo "Run programm B for ${TARGET} & ${WORKNODE_NAME}"
 fi