Bash scripts to pull, (optional) retag, save, load and push Docker images. Created to provide easy means to download an image, retag it to use a private registry and then save it to an external disk. In a offline or on-premise environment you can use the load and push script to load images and push them to a private registry.

docker-load-and-push.sh

#!/bin/bash

#### Functions ###
display_usage() { 
	echo "This script must be run with Docker capable privileges and you should login to your registry before pushing!" 
	echo -e "\nUsage:\n$0 <saved_image> [--push]\n" 
	echo -e " <saved_image>\t\t\tThe image file to load and push" 
	echo -e " [--push]\t\t\tPush to registry" 	
	echo -e "\nExample: $0 /mydir/ubuntu.tar --push "
} 

# Check params
if [  $# -le 0 ] 
then 
	display_usage
	exit 1
fi 

# Check Docker command executable exit code
docker images > /dev/null 2>&1; rc=$?;
if [[ $rc != 0 ]]; then 
	display_usage
	exit 1
fi

echo -e "\nLoading $1..." 

# Load image and save output
RESULT=$(docker load -i $1)

# Get image name and registry
IMAGE=${RESULT#*: }
REGISTRY=${IMAGE#*\/}

echo $RESULT 

# Push if flag provided
if [[ $* == *--push* ]]; then

	echo -e "\nPushing $IMAGE to $REGISTRY..." 
	docker push $IMAGE

	# Check result
	if [[ $rc != 0 ]]; then 
		echo -e "\nERROR: Push failed, are you logged in to $REGISTRY? (e.g. \$ docker login $REGISTRY)" 
		exit 1
	fi

fi

echo "Done!"
exit 0

docker-save-and-retag.sh

#!/bin/bash

#### Functions ###
display_usage() { 
	echo "This script must be run with Docker capable privileges!" 
	echo -e "\nUsage:\n$0 <image> <save_to_file> [retag_name] \n" 
	echo -e " <image>\t\t\tThe image to pull" 
	echo -e " <save_to_file>\t\t\tFilename to save the image to" 
	echo -e " [retag_name]\t\t\t(Optional) new name (tag) for image" 
	echo -e "\nExample: $0 mysql/mysql-server:latest /mydir/mysql.tar my.private.registry/mysql/mysql-server:latest"
} 

# Check params
if [  $# -le 1 ] 
then 
	display_usage
	exit 1
fi 

# Check Docker command executable exit code
docker images > /dev/null 2>&1; rc=$?;
if [[ $rc != 0 ]]; then 
	display_usage
	exit 1
fi

# Pull image
docker pull $1

# Set image name to save
IMAGE=$1

# Retag image if retag name give
if [ ! -z "$3" ]; then
	docker tag $1 $3
	echo "Retaged $1 to $3" 
	
	# Overwrite image to save
	IMAGE=$3
fi

# Save to output file
docker save -o $2 $IMAGE
echo "Saved $IMAGE to $2" 

# Untag image if retag name give
if [ ! -z "$3" ]; then
	docker rm $IMAGE
fi

echo "Done!"
exit 0