Download and insert salt string inside wordpress wp-config.php with Bash

Question

How can I insert the content of the variable $SALT in a specific point (line or string) of a file like wp-contet.php from wordpress using Bash script?

Answer 1

I was challenged with the same issue. Here is the script I wrote to replace the salts and keys from ones downloaded from WordPress. You can use it at any time to replace them if/when needed. I run it as sudo, and the script tests for that. If you use an account that can download to the directory and make updates to the wp-config.php file, then you can delete that part of the script.

#!/bin/sh
# update-WordPress-Salts: Updates WordPress Salts
# written by Wayne Woodward 2017

if [ $# -lt 1 ]; then
    echo "Usage: update-WordPress-Salts directory"
    exit
fi

if [ "$(whoami)" != "root" ]; then
  echo "Please run as root (sudo)"
  exit
fi

WPPATH=$1

# Update the salts in the config file

# Download salts from WordPress and save them locally
curl http://api.wordpress.org/secret-key/1.1/salt/ > /var/www/$WPPATH/wp-keys.txt

# Iterate through each "Saltname" and append 1 to it
# For a couple names that may match twice like "AUTH_KEY" adds extra 1s to the end
# But that is OK as when this deletes the lines, it uses the same matching pattern
# (Smarter people may fix this)
for SALTNAME in AUTH_KEY SECURE_AUTH_KEY LOGGED_IN_KEY NONCE_KEY AUTH_SALT SECURE_AUTH_SALT LOGGED_IN_SALT NONCE_SALT
do
   sed -i -e "s/$SALTNAME/${SALTNAME}1/g" /var/www/$WPPATH/wp-config.php
done

# Find the line that has the updated AUTH_KEY1 name
# This is so we can insert the file in the same area
line=$(sed -n '/AUTH_KEY1/{=;q}' /var/www/$WPPATH/wp-config.php)

# Insert the file from the WordPress API that we saved into the configuration
sed -i -e "${line}r /var/www/$WPPATH/wp-keys.txt" /var/www/$WPPATH/wp-config.php

# Itererate through the old keys and remove them from the file
for SALTNAME in AUTH_KEY SECURE_AUTH_KEY LOGGED_IN_KEY NONCE_KEY AUTH_SALT SECURE_AUTH_SALT LOGGED_IN_SALT NONCE_SALT
do
   sed -i -e "/${SALTNAME}1/d" /var/www/$WPPATH/wp-config.php
done

# Delete the file downloaded from Wordpress
rm /var/www/$WPPATH/wp-keys.txt