Running Bash Script as root with non root script section

I have a bash script that needs to run as root to accomplish a task in this case it is to make the validator take a snapshot of the Helium blockchain.

I have edited the /etc/sudoers file to allow me to run this script as root. This works fine.

useraccount   ALL=(ALL:ALL) NOPASSWD:/home/useraccount/validator_data/snapshotmaker.sh

The command in the script is as follows:

sudo docker exec validator miner snapshot take /var/data/$dtt

after this, the command generates a file like this '30-10-2021T233752.bin'.

My next step is to take this file and copy it to IPFS so I can share it. The command to do this is:

ipfs files cp /ipfs/$(ipfs add -Q $localfile) $ip

At the moment I get the following error:

Error: no IPFS repo found in /root/.ipfs. please run: 'ipfs init'

This is because it is trying to run it as root when the configuration is in my useraccount.

I have tried to switch accounts in the middle of the script but it seems to kill it.

So my question is how to run the IPFS command as my original user from within the root script.

My Bash Scrip:

#!/bin/bash

dt=$(date '+%d-%m-%YT%H%M%S');
dtt="${dt}.bin"
a='/var/data/'
c="${a}${dt}.bin"

echo "${c}"

sudo docker exec validator miner snapshot take /var/data/$dtt


localfile="/home/useraccount/validator_data/${dt}.bin"
echo "LocalFile: ${localfile}"

ip=" /Helium/Snapshots/2021/${dt}.bin"
echo "IPFS Location: ${ip}"

sleep 2

if [ -f "$localfile" ]; then
        echo "$localfile exists."
        sudo chown useraccount $localfile
        whoami
        su - useraccount
        whoami
        ipfs files cp /ipfs/$(ipfs add -Q $localfile) $ip
        #ipfs files cp /ipfs/$(ipfs add -Q <local-file>) "/Helium/Snapshots/2021/<dest-name>"
else 
    echo "$localfile does not exist."
fi

The output is as follows:

/var/data/31-10-2021T005728.bin
ok
LocalFile: /home/useraccount/validator_data/31-10-2021T005728.bin
IPFS Location:  /Helium/Snapshots/2021/31-10-2021T005728.bin
/home/useraccount/validator_data/31-10-2021T005728.bin exists.
root

And then it dies. If I remove the su line then I get the root issue as mentioned at the top of this post.

Hoping someone can help.

First, you need to create a sudo configuration for your script, in this example, we place it in /etc/sudoers.d with permission 440:

Cmnd_Alias CMDS = /opt/bin/docker_example.sh
User_Alias CMDUSERS = bac0n
CMDUSERS ALL=(ALL) NOPASSWD: CMDS
Defaults!CMDS !requiretty

We name the script docker_example.sh, as shown in the sudo example:

#!/bin/bash

# Exit immediately on non-zero exit status.
set -e

((EUID != 0)) && {
    echo This script should run as root.
    exit 1
}

[[ ${SUDO_USER+ } ]] && \
user_account=$SUDO_USER || user_account=$(id -nu)

printf -v bin_file \
'%(%d-%m-%YT%H%M%S)T.%s' -1 bin

local_file=$HOME/validator_data/$bin_file
 ipfs_file=/Helium/Snapshots/2021/$bin_file

printf '
Bin File: %s
Local File: %s
IPFS File: %s
' "$bin_file" "$local_file" "$ipfs_file"

docker exec validator miner snapshot take "/var/data/$bin_file"
sleep 2

[[ -f $local_file ]] || {
    echo File does not exist: "$local_file"
    exit 1
}

chown $user_account "$local_file"

#
# su $user_account -c 'echo whoami: $1, su: $(id -nu)' _ $(id -nu)
#
su $user_account -c 'ipfs files cp "/ipfs/$(ipfs add -Q "$1")" "$2"' _ "$local_file" "$ipfs_file"

Now you should be able to add this script with sudo to crontab, and it should run with NOPASSWD.

$ sudo crontab -u bac0n -e
# min hour dom month dow command
* * * * * sudo /opt/bin/docker_example.sh > /dev/null 2>&1

So my question is how to run the IPFS command as my original user from within the root script.

sudo su - useraccount -c COMMAND