db-dump.sh

#!/bin/sh
#
# Exports a database to a file and uploads it to Google Drive.

# Bail out if there are any errors.
set -e

dir=$(dirname `readlink -f $0`)

# Ensure the gdrive utility is installed
command -v gdrive >/dev/null 2>&1 || { echo >&2 "gdrive (https://github.com/prasmussen/gdrive) command line utility is required but not installed. Aborting."; exit 1; }

if [ "$1" = 'config' ]; then
	overwrite="y"
	if [ -f "$dir/db-dump.conf"  ]; then
		read -p "Config file already exists, overwrite? (Y/n): " overwrite
		if [ "$overwrite" != "n" ]; then
			overwrite="y"
		fi
	fi

	if [ "$overwrite" = "y" ]; then
		echo "Generating config file..."
		read -p "Enter Database Name: " userdb_name
		read -p "Enter Google Drive Folder ID: " usergdrive_folder_id

		cp "$dir/db-dump.conf.dist" "$dir/db-dump.conf"
		sed -i "s/db_name=\"\"/db_name=\"$userdb_name\"/" "$dir/db-dump.conf"
		sed -i "s/gdrive_folder_id=\"\"/gdrive_folder_id=\"$usergdrive_folder_id\"/" "$dir/db-dump.conf"

		echo "Config file generated."
	else
		echo "Aborting."
	fi

	exit
fi

# Ensure we have a conf file
if ! [ -f "$dir/db-dump.conf" ]; then
	echo >&2 "Config file does not exist, run '$0 config' to generate it. Aborting."
	exit 1
fi

# Load config file
. "$dir/db-dump.conf"

# Allow config overrides per user
if [ -f "$HOME/.config/db-dump.conf" ]; then
	. "$HOME/.config/db-dump.conf"
fi

# If an argument is passed and it's a file source it as a config file
if [ "$1" != "" ] && [ -f "$1" ]; then
    . "$1"
    echo "Using '$1' as config file"
fi

# Make sure $db_name and $gdrive_folder_id aren't empty
if [ -z "$db_name" ]; then
	echo >&2 "db_name variable not set. Aborting."
	exit 1
fi

if [ -z "$gdrive_folder_id" ]; then
	echo >&2 "gdrive_folder_id variable not set. Aborting."
	exit 1
fi

# Make sure the local directory exists
mkdir -p "$dump_dir"

# Delete exports older than $retention_days
find "$dump_dir" -type f -name "*.sql.gz" -mtime +"$retention_days" -exec rm -f "{}" \;

# Compress any existing export files
find "$dump_dir" -type f -name "*.sql" | while read -r file; do
    gzip "$file"
    # Upload the .sql.gz file
    gdrive upload --no-progress --parent "$gdrive_folder_id" "$file.gz"

    # Delete the .sql file from Google Drive
    file_id=$(gdrive list --no-header --query "'$gdrive_folder_id' in parents and name = '$(basename "$file")'" | head -n1 | awk '{print $1}')
    if [ "$file_id" ]; then
        gdrive delete "$file_id"
    fi
done

# Dump the live database to a file
dump_file="$db_name-$(date +$date_format).sql"
path="$dump_dir/$dump_file"
mysqldump $mysql_opts "$db_name" > "$path"

# Upload the newly created file to Google Drive
gdrive upload --no-progress --parent "$gdrive_folder_id" "$path"

# Delete remote export files older than $retention_days
for file_id in $(gdrive list --no-header --query "'$gdrive_folder_id' in parents and modifiedTime <= '$(date --date="$retention_days days ago" --iso-8601="seconds")'" | awk '{print $1}'); do
    gdrive delete "$file_id"
done