replace-missing-repl

#!/usr/bin/env bash
#
# Usage:
#  replace-missing-repl
#
# This program fixes a set of data objects that a have a replica missing its
# physical file. It does this by copying a known good replica of a data object
# that has the same checksum. It reads the set of data object replica fixes from
# stdin. There is one fix per line with each fix having five tab-separated
# fields. A fix has the following form.
#
# <data obj>	<bad resc>	<bad repl>	<good resc>	<replacement repl>
#
# Here <data obj> is the absolute, logical path to the data object read from
# stdin; <bad resc> is the name of the storage resource hosting the bad replica;
# <bad repl> is the absolute, physical path to the bad replica; <good resc> is
# the name of the storage resource hosting the replacement replica; and
# <replacement repl> is a replica that has the same checksum as the bad replica.
#
# This script is intended to read the output if `missing-repl-replacements`.

set -o errexit -o nounset -o pipefail

declare StagedRepl

main() {
	StagedRepl="$(mktemp)"
	trap 'rm --force "$StagedRepl"' EXIT

	local needyObj needyResc missingRepl givingResc goodRepl
	while IFS=$'\t' read -r needyObj needyResc missingRepl givingResc goodRepl; do
		printf 'Recovering %s\n' "$needyObj"

		rm --force "$StagedRepl"

		local missingReplDir
		missingReplDir="$(dirname "$missingRepl")"

		if ! scp -q -P 1657 "$givingResc":"$(printf '%q' "$goodRepl")" "$StagedRepl"; then
			printf 'ERROR: Good replica not found at %s:%s\n' "$givingResc" "$goodRepl"
			continue
		fi

		# shellcheck disable=SC2029
		ssh -q -p 1657 "$needyResc" sudo --user=irods mkdir --parents "'$missingReplDir'" < /dev/null

		scp -q -P 1657 "$StagedRepl" "$needyResc":"$(printf '%q' "$missingRepl")"

		# shellcheck disable=SC2029
		ssh -q -p 1657 "$needyResc" chown irods.irods "'$missingRepl'" < /dev/null

		printf 'Recovered %s\n' "$needyObj"
	done
}

main "$@"