Over the past couple of years, becoming comfortable with Linux has been one of the most valuable things I’ve done as a web developer and I’m always looking for ways to learn more. Diving in to shell scripting has been on the to-do list for a while now so here’s a case where I had an opportunity to automate a simple task with a couple of bash scripts.
I backup and restore WordPress installations pretty frequently. Sometimes it’s because I’m going to make some change that could dramatically affect the installation, like converting to a network install, and I want to make sure it’s backed up in case I break something; other times I’m moving an installation from one environment to another, Like if I wanted to move the production installation to a development server to test updates; and of course, sometimes you just need to create scheduled backups.
Backing up and restoring WordPress manually is a tedious process and if I find myself needing to do it in the middle of working on something, it can really throw my focus off so it seemed like the perfect task to automate.
So why not use an existing tool? There are a ton of WordPress backup solutions out there but none of them do exactly what I want them to do. When it comes to WordPress backups, nothing makes me as comfortable as a copy of the files and a mysqldump file of the database (as opposed to an XML import or some other option). For the sake of this shell scripting exercise that’s what I’ll be doing.
I need two scripts: one to back up WordPress and one to restore it. The backup files will go in a remote location, which in this case is an organizational CIFS share, and the restore script will need to allow a search-replace to be performed on the database as well as the wp-config file in case a back-up is being restored across domains. For the search replace functionality, I’m going to use WP-CLI, a command line interface for WordPress.
To move the backups off the server, we’ll use automount to mount the cifs share to a directory any time we try to access that location. This way our script won’t have to handle the mount, it can just place the files in a directory that’s symlinked to the automount location.
For abstraction, I’ve added the following environment variables to ~/.bashrc:
#Environment Variables for WordPress backup and restore #HOSTNAME should already be defined Ex:sitedevl export WORDPRESS_DATABASE_NAME=wordpressdbname export WORDPRESS_DATABASE_USER=wordpressdbuser export WORDPRESS_HOME_DIRECTORY=/var/www/wordpress/public export WORDPRESS_BACKUP_DIRECTORY=~/wpbackups export WORDPRESS_SQL_FILE_NAME=wordpress.sql
And I don’t want any passwords in my script so the mysql and mysqldump credentials will go in ~/.my.cnf
[mysqldump] user=wordpressdbuser password=wordpressdbpassword [mysql] user=wordpressdbuser password=wordpressdbpassword
For the restore script, I’ll also need to install WP-CLI by placing it in ~/bin, renaming it to wp and changing permissions to 755.
Once we have all of that set up, the scripts just need to be placed in ~/bin and permissions need to be set to 755.
wpdump
#!/bin/sh
#Backs up WordPress
#File structure
# wpbackups
# |_year-month-day
# |_sql
# |_dumpfile.sql
# |_html
# |_wordpress files...
#mysqldump vars stored in ~my.conf
#permissions may be required to create directories
#set -e
#The following environment variables should be defined in ~./bashrc
#export WORDPRESS_DATABASE_NAME=wordpressdbname
#export WORDPRESS_DATABASE_USER=wordpressdbuser
#export WORDPRESS_HOME_DIRECTORY=/var/www/wordpress/public
#export WORDPRESS_BACKUP_DIRECTORY=~/wpbackups
#export WORDPRESS_SQL_FILE_NAME=wordpress.sql
WORDPRESS_TIMESTAMPED_BACKUP_DIRECTORY=${WORDPRESS_BACKUP_DIRECTORY}/${HOSTNAME}-`date +"%F-%H-%M"`
WORDPRESS_SQL_DIRECTORY=${WORDPRESS_TIMESTAMPED_BACKUP_DIRECTORY}/sql/
WORDPRESS_FILE_DIRECTORY=${WORDPRESS_TIMESTAMPED_BACKUP_DIRECTORY}/html/
#testing
SUCCESS="completed successfully"
FAILURE="failed"
red='\033[0;31m'
green='\033[0;32m'
nc='\033[0m'
Test() {
if [[ $? == 0 ]]; then
echo -e "${green}$1 ${SUCCESS}${nc}"
else
echo -e "${red}$1 ${FAILURE} Exiting! ${nc}"
exit
fi
}
echo -e "${green}Backing Up WordPress!${nc}"
#Create wpbackup directory if there isnt one
mkdir -p ${WORDPRESS_BACKUP_DIRECTORY};
#Check for existing directory
if [[ -d "$WORDPRESS_TIMESTAMPED_BACKUP_DIRECTORY" ]]; then
#Remove existing backup directory if there is one
echo "remove existing backup directory"
rm -Rf ${WORDPRESS_TIMESTAMPED_BACKUP_DIRECTORY};
#Test Remove Backup Directory
Test "remove exisiting backup directory"
fi
#Create Backup Directory
echo "create backup directory"
mkdir -p ${WORDPRESS_SQL_DIRECTORY};
#Test Create Backup Directory
Test "create backup directory:"
#Dump Database
echo "Dump Database"
mysqldump -u${WORDPRESS_DATABASE_USER} ${WORDPRESS_DATABASE_NAME} > ${WORDPRESS_SQL_DIRECTORY}${WORDPRESS_SQL_FILE_NAME};
#Test Dump Database
Test "Dump Database"
#Show the results
#echo "${WORDPRESS_SQL_FILE_NAME} was created:"
#ls -l ${WORDPRESS_SQL_DIRECTORY}${WORDPRESS_SQL_FILE_NAME}
#Copy Files
echo "Copy Files"
rsync -rv --exclude=*.log ${WORDPRESS_HOME_DIRECTORY} ${WORDPRESS_FILE_DIRECTORY};
#Test Copy Files
Test "Copy Files"
echo -e "${green}All Done!${nc}"
wprestore
#!/bin/sh
#restores WordPress
#-n skips backup before restoring
USAGE="usage: wprestore -b=[backupdirectory] -s=[searchstring] -r=[replacestring] -n"
#testing
SUCCESS="completed successfully"
FAILURE="failed"
#colors
red='\033[0;31m'
green='\033[0;32m'
nc='\033[0m'
#Function to test commands
Test() {
if [[ $? == 0 ]]; then
echo -e "${green}$1 ${SUCCESS}${nc}"
else
echo -e "${red}$1 ${FAILURE} Exiting! ${nc}"
exit
fi
}
# parse the options and define variables
while getopts 's:r:b:n' opt ; do
case $opt in
s) SEARCH=$OPTARG ;;
r) REPLACE=$OPTARG ;;
b) BACKUP_DATE=$OPTARG ;;
n) NO_BACKUP=1;;
esac
done
#check backup directory
if [ -z ${BACKUP_DATE} ]
then
echo -e "${red}No backup date specifiedn${USAGE}${nc}"
exit;
else
BACKUP=${WORDPRESS_BACKUP_DIRECTORY}/${BACKUP_DATE}
echo -e "${green}Restoring Backup: ${BACKUP}${nc}"
fi
#backup current state
if [ -z ${NO_BACKUP} ]
then
wpdump
else
echo "Skipping backup"
fi
#Delete WP Directory Contents
echo "Delete WP Directory Contents";
rm -rf ${WORDPRESS_HOME_DIRECTORY}/*;
Test "Delete WP Directory Contents";
#Copy backed up files to main directory
echo "Copy backed up files to main directory"
echo "Copying ${BACKUP}/html to ${WORDPRESS_HOME_DIRECTORY}"
cp -r ${BACKUP}/html/* ${WORDPRESS_HOME_DIRECTORY};
Test "Copy backed up files to main directory"
#Drop existing database
echo "Drop existing database"
mysql -u${WORDPRESS_DATABASE_USER} -e "DROP DATABASE IF EXISTS ${WORDPRESS_DATABASE_NAME}";
Test "Drop existing database"
#Create wordpress database
echo "Create WordPress database"
mysql -u${WORDPRESS_DATABASE_USER} -e "CREATE DATABASE IF NOT EXISTS ${WORDPRESS_DATABASE_NAME}";
Test "Create WordPress database"
#restore database
echo "Restore WordPress database"
mysql -u${WORDPRESS_DATABASE_USER} ${WORDPRESS_DATABASE_NAME} < ${BACKUP}/sql/wordpress.sql;
Test "Restore WordPress Database"
#Search and replace database with new names
#check search and replace strings
if [ -z ${SEARCH} ] || [ -z ${REPLACE} ]
then
echo "Search replace strings not defined"
else
#Search and Replace daatabase
echo -e "Replacing ${SEARCH} with ${REPLACE} in the database";
wp search-replace --network --url=${SEARCH} ${SEARCH} ${REPLACE} --precise;
Test "search-replace database"
#search and replace wpconfig file
echo "Search replace file"
sed -i 's/${SEARCH}/${REPLACE}/g' ${WORDPRESS_HOME_DIRECTORY}/wp-config.php;
fi
echo 'All done!'
I’ve already gotten some flak from friends that this is overkill. There’s always a better way to do everything, though, and this is a million times better than how I was doing this before. What was a ten minute manual process, now only takes a minute with a couple of commands.
This is actually the first time I’ve written a shell script that automates something I actually do often. It was also the first time I’ve been formally introduced to defining environment variables, setting up symlinks, using mount and automount, using sed to search and replace in a file from the command line, using colors in the shell, and a bunch of other cool stuff. So regardless of whether or not they’re perfect, I learned a ton.
I was fortunate enough to have a lot of people helping me out with this including my coworker, whose name may or may not start with a J, and several folks from the memtech community especially @speakingcode and @edyesed. Also thanks to @eterps for introducing me to WP-CLI.