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Remove Quotes From Strings

Here’s the command to remove quotes from a string in Bash by using the tr -d command. I’m using jq tool to extract the access key from a json file. Bash returns a string surrounded by quotes. To remove the quotes, just pipe the string to the tr -d command.

jq .AccessKey.AccessKeyId key.json

Result:

"ASDFSDFSDFASDFSDFSDFGHGDF"

Using tr -d.

jq .AccessKey.AccessKeyId key.json | tr -d \"

Result:

ASDFSDFSDFASDFSDFSDFGHGDF

Bash Variables

Here’s how to read Bash variables from another file.

Contents of config.sh

#!/bin/bash
var1='thisisvariableone'
var2='thisisvariabletwo'

Call config.sh from another script.

#!/bin/bash
source config.sh
echo var1
echo var2

This is extremely helpful if you have multiple scripts using a common variable. You just to update one file instead of multiple files. All the other scripts will read and pick up the same variables from a config file. You can use this to setup your global variables.

GCE Agent Bash

This is a Bash script to restart a service.

#!/bin/bash
 
SERVICE=google_osconfig_agent
AGENT=google-osconfig-agent
 
if (( $(ps -ef | grep -v grep | grep $SERVICE | wc -l) > 0 ))
then
    echo "$AGENT service running, everything is fine"
else
    echo "$AGENT is not running"
    echo "Restarting service"
    systemctl start $AGENT
    sleep 5s
    if (( $(ps -ef | grep -v grep | grep $SERVICE | wc -l) > 0 ))
    then
      sleep 2s
      echo "$AGENT service is now running"
    fi
fi