I'd like a bit of help refactoring a couple of bash scripts

README.md

Backup Script

What is this?

These two files are what I use to create regular backups on our websites. They create a sql dump of the database, and then a tarball of the directory structure.

Specific Help required

This is all fine, but I want to find a way that a message will be sent to slack if one of the other commands (or the whole script) fails. EG - tar failed because filesystem run out of space; or mysqldump failed because wrong password? or simply 'couldn't find folder!?, etc!

I'd really appreciate any pointers, or help in simplifing the script too!

Get in touch

• Either in the comments below
• Twitter @fredbradley
• DevChat team on Slack (http://devolio-devchat.slack.com) - where I am @fredbradley

backup.sh

#!/bin/sh

############################################################################
## 			So - there is one `backup.sh` for each site on the server.        ##
##      The content is largely the same, just a change of variables to    ##
##      ensure things are saved in the write places with the right names! ##
############################################################################

## REQUESTS FOR SPECIFIC HELP
# This is all fine, but I want to find a way that a message will be sent to slack if one of the other commands (or the whole script) fails. 
# EG - `tar` failed because filesystem run out of space; or `mysqldump` failed because wrong password? or simply 'couldn't find folder!?, etc!


## Load in Functions File (See above file in GIST)
source "/root/backup_functions_frb/functions.sh"

# Color Variables 
RED='\033[0;31m'
GREEN='\033[0;32m'
NC='\033[0m' # No Color

# 1. SET VARIABLES
	SITE_NAME="www.mydomain.org"
	
  DATABASE_NAME="freds_test_db"
	
  # Notice this variable gets picked up in `functions.sh`
  SLACK_NAME="BACKUP TEST USER"
  
  # Get the path directory to 'here'. (No need to add in more changing variables so long as file/directory structure always the same)
	PATH_DIRECTORY="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
  
  # Although called "BACKUPTIME" this is effectivly the file name.
	BACKUPTIME="$SITE_NAME-$(date +"%Y-%m-%d")"
  
  # Each site has an 'auto_backups' folder as part of it's structure
	BACKUP_DIRECTORY="$PATH_DIRECTORY/auto_backups"

  # Tell Slack that we're starting
	slackWrite "Starting backup script: 'backup.sh'"
	
  # Tell shell output that we're starting
	echo -e "${GREEN}Starting MySQL Backups...${NC}"
	slackWrite "Starting MySQL Dump"

# 2. DO LATEST MYSQL
	mysqldump $DATABASE_NAME > $PATH_DIRECTORY/latest-dump_$DATABASE_NAME.sql

	echo -e "${GREEN}Placed the latest backup in the file system...${NC}"
	slackWrite "Dumped latest MySQL in filesystem"

# 3. DO MYSQLDUMP
	echo -e "${GREEN}Now backing up to backups folder... ${NC}"
	mysqldump $DATABASE_NAME > $BACKUP_DIRECTORY/$BACKUPTIME.sql
	echo -e "${GREEN}Starting GZIP${NC}"

	gzip $BACKUP_DIRECTORY/$BACKUPTIME.sql

	echo -e "${GREEN}Completed MySQL Backup${NC}"

# 4. DO FILE BACKUP
	echo -e "${GREEN}Starting Filesystem Backup... sit back this takes a while...${NC}"
	slackWrite "Starting Filesystem Backup..."

	tar -zcvf $BACKUP_DIRECTORY/$BACKUPTIME.tar -C $PATH_DIRECTORY doc_root/ wp-config.php
	
	echo -e "${GREEN}Starting GZIP${NC}"

	gzip $BACKUP_DIRECTORY/$BACKUPTIME.tar
	
	echo -e "${GREEN}Completed Filesystem backup Backup${NC}"
	slackWrite "Completed Filesystem Backup"

# 5. FIND AND DELETE OLD FILES more than 7 days
	echo -e "${GREEN}Checking if I need to delete any old backups...${NC}"
	slackWrite "Checking if I need to delete any old backups..."

	array=($(find $BACKUP_DIRECTORY -type f -mtime +6))
	for i in ${array[@]};
	
	    do
			name=$(basename "$i")
			echo -e "${RED}Deleted $i backup ${NC}"
			slackWrite "Deleted $name"

			rm $i

	done;
	
	echo -e "${GREEN}All 100% Done${NC}"

	slackWrite "<!here> Completed: 'backup.sh'"

functions.sh

#!/bin/sh

# A function that will post a CURL request to Slack
function slacker {
	# Usage: slacker <channel> <username> <message>

	webhookuri='< OMITTED FORM PUBLIC GIST >'
	
	# Get Channel Name
	channel=$1
	if [[ $channel == "" ]]
	then
		echo "No channel specified"
		exit 1
	fi

	shift

	# Get Username you want to be displayed as
	username=$1
	if [[ $username == "" ]]
	then
		echo "No Username specified"
		exit 1
	fi

	shift

	# Get Text
	text=$*

	if [[ $text == "" ]]
	then
		echo "No text specified"
		exit 1
	fi

	escapedText=$(echo $text | sed 's/"/\"/g' | sed "s/'/\'/g" )

  json="{\"username\": \"$username\", \"channel\": \"#$channel\", \"text\": \"$escapedText\"}"

	curl --silent --data "payload=$json" "$webhookuri"
  #TODO: Is there a way to stop the script (when run in terminal) to surpress the "ok" resposne that this CURL recieves? 
  # (I thought that's what `--silent` did!)
}

# A shorthand helper function that users the main `slacker` function written above.
# $SLACK_NAME is a variable pulled in from `backup.sh`. 
function slackWrite {
        # Usage: slackWrite <message>

        text=$*
        slacker website-app-logs "$SLACK_NAME" $text
}

# Function deprecated due to a superior method used above. 
# Will be removed in a future version.
function quickslack {
	# Usage: quickslack <message>

	text=$*
	slacker website-project cranlive $text
}