Using getopt(s) to run specific parts of script when parameter is passed at runtime

Question

I've written a long bash script for configuring an SSH daemom, etc on android. Problem is, it has gotten too long & at times other users or I may only want to configure certain aspects of what the script has to offer. Instead of having to go through entire script each time it is ran I would like to add options that dictate what will be ran but still be able to run script as whole when nothing is specified.

Something like:

myscript -d -o -p

Or

myscript -dop    

The script can be found here. I think its too long to be posted here.

Basically it's broke up into 5 blocks like this:

#!/system/xbin/bash

echo "---SECTION-ONE---"

read
if test then  

while true
do

I looked up using getopts and can't quite wrap my head around it just yet without an example that matches with what I'm doing. Thats why I'm posting here ;) As always thanks for any inpout.

Answer 1

You can break down the different bodies of the script into functions that can be called when an option is present.

#!/bin/bash

printing_stuff (){
    echo "---SECTION-ONE---"
}

test_input (){
    read -p "Enter something: " input
    if [[ $input == something ]]; then
        echo "test successful"
        # do some stuff
    fi
}

body_loop (){
    while true; do
        echo "this is the loop"
        # some stuff
        break
    done
}

if [[ $@ ]]; then
    while getopts "dop" opt; do
        case $opt in
            d)
                printing_stuff
                ;;
            o)
                test_input
                ;;
            p)
                body_loop
                ;;
            \?)
                ;;
        esac
    done
else
    printing_stuff
    test_input
    body_loop
fi

The [[ $@ ]] test is done to only run the getopts loop if arguments to the script exist, otherwise run everything.