Noob-level shell script allowing dumping a pgsql database running on an openshift pod in a file.

oc-postgre-backup.sh

#!/bin/sh

# oc-postgre-backup
# creates a backup file for a postgre database running on an openshift pod
# ------------------
# requires:
# - oc  - openshift client, allowing connecting to the postgre pod
# - pg_dump - part of the postgresql package, allowing creating the dump file from the database
# ------------------
# arguments:
# - url - url of the openshift instance
# - token - authentication token to use for connecting to openshift
# - namespace - openshift namespace in which the database pod is running
# - pod - pod name in which the postgre database is running (not actual name, it'll be grepped)
# - username - username to be used for connecting to the database
# - dbname - name of the database to backup
# - oc - (optional) path to the oc binary
# - proxyHost - (optional) host of the proxy to use
# - proxyPort - (optional) port of the proxy to use
# - noProxy - (optional) list of non proxy hosts
# - verbose - (optional) writes more logs
# - help - (optional) displays help information about the program
# - debug - (optional) displays values retrieved from all parameters
# ------------------
# Execution example:
# ./oc-postgre-backup --url openshift_url --token your_token --namespace your_namespace --pod postgre --username your_username --dbname your_db --oc /home/user/tools/oc --proxyHost http://someProxy --proxyPort 1234 --noProxy localhost,127.0.0.1 --verbose --help --debug
# ------------------
# Author: [email protected]
# Version: 0.1

# ------------------
# Helper functions
# ------------------

log() {
	if [[ -n $VERBOSE ]]; then
		echo "$1"
	fi
}

# ------------------
# Welcome!
# ------------------

echo "[oc-postgre-backup] - Hello!"
echo "Parsing all arguments... (use --debug to check the arguments used)"

# ------------------
# Arguments Parsing
# ------------------

REMAINING=()

while [[ $# -gt 0 ]]
do
key="$1"

case $key in
    --url)
    URL="$2"
    shift # past argument
    shift # past value
    ;;
    --token)
    TOKEN="$2"
    shift # past argument
    shift # past value
    ;;
    --namespace)
    NAMESPACE="$2"
    shift # past argument
    shift # past value
    ;;
	--pod)
    POD="$2"
    shift # past argument
    shift # past value
    ;;
    --username)
    USERNAME="$2"
    shift # past argument
    shift # past value
    ;;
    --dbname)
    DBNAME="$2"
    shift # past argument
    shift # past value
    ;;
    --oc)
    OC="$2"
    shift # past argument
    shift # past value
    ;;
    --proxyHost)
    PROXYHOST="$2"
    shift # past argument
    shift # past value
    ;;
    --proxyPort)
    PROXYPORT="$2"
    shift # past argument
    shift # past value
    ;;
    --noProxy)
    NOPROXY="$2"
    shift # past argument
    shift # past value
    ;;
    --verbose)
    VERBOSE=true
    shift # past argument
    ;;
	--help)
    HELP=true
    shift # past argument
    ;;
    --debug)
    DEBUG=true
    shift # past argument
    ;;
    *)    # unknown option
    REMAINING+=("$1") # save it in an array for later
    shift # past argument
    ;;
esac
done
set -- "${REMAINING[@]}" # restore positional parameters

# ------------------
# Displaying debug information if needed
# ------------------

if [[ -n $DEBUG ]]; then

	echo "------------------"
	echo "oc-postgre-backup [DEBUG]"
	echo "------------------"
	echo "URL		= ${URL}"
	echo "TOKEN		= ${TOKEN}"
	echo "NAMESPACE	= ${NAMESPACE}"
	echo "POD		= ${POD}"
	echo "USERNAME	= ${USERNAME}"
	echo "DBNAME  	= ${DBNAME}"
	echo "OC		= ${OC}"
	echo "PROXYHOST	= ${PROXYHOST}"
	echo "PROXYPORT	= ${PROXYPORT}"
	echo "NOPROXY 	= ${NOPROXY}"
	echo "VERBOSE 	= ${VERBOSE}"
	echo "HELP		= ${HELP}"
	echo "DEBUG		= ${DEBUG}"
	echo "------------------"

fi

# ------------------
# Validating mandatory parameters are provided
# ------------------

log "Checking if [url] parameter was provided..."
if ! test -n "$URL"; then
  echo "ERROR! [url] parameter is mandatory!"
  exit
fi
log "[url] is found!"

log "Checking if [token] parameter was provided..."
if ! test -n "$TOKEN"; then
  echo "ERROR! [token] parameter is mandatory!"
  exit
fi
log "[token] is found!"

log "Checking if [namespace] parameter was provided..."
if ! test -n "$NAMESPACE"; then
  echo "ERROR! [namespace] parameter is mandatory!"
  exit
fi
log "[namespace] is found!"

log "Checking if [pod] parameter was provided..."
if ! test -n "$POD"; then
  echo "ERROR! [pod] parameter is mandatory!"
  exit
fi
log "[pod] is found!"

log "Checking if [username] parameter was provided..."
if ! test -n "$USERNAME"; then
  echo "ERROR! [username] parameter is mandatory!"
  exit
fi
log "[username] is found!"

log "Checking if [dbname] parameter was provided..."
if ! test -n "$DBNAME"; then
  echo "ERROR! [dbname] parameter is mandatory!"
  exit
fi
log "[dbname] is found!"

# ------------------
# Validating thirdparties are installed
# ------------------

log "Validating thirdparties are installed..."
log "Searching for pg_dump..."
if ! command -v pg_dump &> /dev/null
then
    echo "[pg_dump] is required, please install it."
    exit
fi
log "[pg_dump] found!"
log "Searching for oc..."
if [[ -n $OC ]]; then
	log "Searching for custom oc installation..."
	if ! command -v $OC &> /dev/null
	then
    	echo "[${OC}] can't be found, please check the parameter you provided."
    	exit
	else
		OCBINARY=$OC
	fi
else
	log "Searching for oc..."
	if ! command -v oc &> /dev/null
	then
    	echo "[oc] is required, please install it."
    	exit
	else
		OCBINARY=oc
	fi
fi
log "[oc] found!"
log "Using ${OCBINARY}."

# ------------------
# Configuring proxy
# ------------------

log "Checking if proxy needs to be configured..."
if [[ -n $PROXYHOST ]]; then

	log "Configuring proxy with provided information..."
	log "Storing backup of actual proxy configuration..."

	BAK_PROXY=$PROXY
	BAK_HTTP_PROXY=$HTTP_PROXY
	BAK_HTTPS_PROXY=$HTTPS_PROXY
	BAK_NO_PROXY=$NO_PROXY

	log "Backup of [${BAK_PROXY} / ${BAK_HTTP_PROXY} / ${BAK_HTTPS_PROXY} / ${BAK_NO_PROXY}] done."

	log "Setting up provided proxy configuration..."
	export PROXY="${PROXYHOST}:${PROXYPORT}"
    export HTTP_PROXY=$PROXY
	export HTTPS_PROXY=$PROXY
    export proxy=$PROXY
    export http_proxy=$PROXY
    export https_proxy=$PROXY
	if [[ -n $NOPROXY ]]; then
		export NO_PROXY=$NOPROXY
        export no_proxy=$NO_PROXY
	fi
	log "Proxy configured!"
    log "PROXY = ${PROXY}"
    log "NO_PROXY = ${NO_PROXY}"
fi

# ------------------
# Searching for database pod
# ------------------

log "Connecting to openshift cluster..."
$OCBINARY login https://$URL --insecure-skip-tls-verify --token=$TOKEN > /dev/null
log "Connected!"
log "Connecting to namespace..."
$OCBINARY project "${NAMESPACE}" > /dev/null
log "Connected!"

log "Identifying pod name from provided pattern (${POD})"
PODNAME=`$OCBINARY get pods -o custom-columns=POD:.metadata.name --no-headers | grep "${POD}"`
log "Found pod running the database: ${PODNAME}!"

# ------------------
# Setting up port-forwarding
# ------------------

log "Setting up port-forwarding to the database..."
$OCBINARY port-forward $PODNAME 15432:5432 > /dev/null &
OCPID=`pidof $OCBINARY`
log "Port forwarding now running at [${OCPID}]"
sleep 5 # waiting a bit for port-forwarding to be effective. it is mandatory.

# ------------------
# Dumping the database to a file
# ------------------

FILENAME="dump_$(date +%Y%m%d_%H%M%S).sql"
log "Dumping the database content in [${FILENAME}]..."
pg_dump --host=localhost --port=15432 --username=$USERNAME --dbname=$DBNAME --format=p --file=./$FILENAME > /dev/null
DUMP_STATUS=$?
if [ $DUMP_STATUS -ne "0" ]; then
  echo "ERROR! [pg_dump] exited with code [${DUMP_STATUS}]."
fi
log "Done!"

# ------------------
# Killing the port-forwarding before leaving
# ------------------

log "Killing port-forwarding before leaving..."
kill $OCPID
log "Killed!"

# ------------------
# Restoring proxy configuration if needed
# ------------------

if [[ -n $BAK_PROXY ]]; then
	log "Restoring proxy configuration back to normal"
	export PROXY=$BAK_PROXY
	export HTTP_PROXY=$BAK_HTTP_PROXY
	export HTTPS_PROXY=$BAK_HTTPS_PROXY
	export NO_PROXY=$BAK_NO_PROXY
    export proxy=$PROXY
    export http_proxy=$HTTP_PROXY
    export https_proxy=$HTTPS_PROXY
    export no_proxy=$NO_PROXY
	log "Proxy restored!"
fi

# ------------------
# Restoring proxy configuration if needed
# ------------------

echo "[oc-postgre-backup] - My job is done!"
exit $DUMP_STATUS # We use the return of pg_dump as exit code to indicate an error if dump is not successful.