Rollback and teardown in bash

Simple rollback

#!/bin/bash

. /path/to/rollback

# create relevant functions:
#   - rollback to initiate rollback
#   - rb to add rollback commands
createRollback rollback rb

# do something

trap rollback INT TERM EXIT

	# create a random file
	touch example

	# remove the file if something fails
	rb rm example

	# create a random file
	touch example2

	# remove the file if something fails
	rb rm example2

	# try removing a file, but do not fail if it does not exist
	rm nonexistent || true

	# this will fail
	rm nonexistent

	# nothing here gets executed
	# the files example and example2 will get removed

trap - INT TERM EXIT

# do something if everything is successful, in this example never gets executed

Teardown

Teardown works just like rollback:

#!/bin/bash

. /path/to/rollback

# create relevant functions:
#   - rollback to initiate rollback
#   - rb to add rollback commands
#   - teardown to initiate teardown
#   - td to add teardown commands
#   - rt to add a command to both the rollback and teardown stack
#   - saveTeardown to save the teardown stack into a file
createRollback rollback rb teardown td rt saveTeardown

# do something

removeFile()
{
	rm example
}

trap rollback INT TERM EXIT

	touch example

	# you can also use functions
	rt removeFile

	# quote anything that should not be evaluated
	td 'rm nonexistent || true'

	# ...

trap - INT TERM EXIT

# do something

# run the teardown commands to remove the files
teardown

# alternatively you could save the commands into a file for later execution:
# saveTeardown script.teardown

Failures

In case of a failure in one of the rollback or teardown commands execution will stop and all commands from all created rollback and teardown stacks will be printed to stderr.

The saved teardown script will just stop.