#!/bin/bash
# {{ ansible_managed }}
# Daily Kopia backup of {{ kopia_backup.hostname }} into the bucket {{ kopia_backup.bucket }} on {{ kopia_backup.endpoint }}.
set -uo pipefail
export KOPIA_CHECK_FOR_UPDATES=false
failed=0
sources=()
{% if kopia_backup.pre_command %}

{{ kopia_backup.pre_command }} || { echo "pre_command failed" >&2; failed=1; }
{% endif %}
{% if kopia_backup.etcd_snapshot %}

# Only the latest etcd snapshot; the live etcd dir is not consistent on disk and older snapshots only add churn
etcd=/var/backups/etcd
latest=$(ls -t /var/lib/rancher/k3s/server/db/snapshots/etcd-snapshot-* 2>/dev/null | head -1)
if [ -n "$latest" ]; then
  install -d -m700 "$etcd"
  rm -f "$etcd/etcd-snapshot"
  ln "$latest" "$etcd/etcd-snapshot" 2>/dev/null || cp -p "$latest" "$etcd/etcd-snapshot" || failed=1
fi
{% endif %}
{% if kopia_backup.dumps %}

dumps=/var/backups/dumps
install -d -m700 "$dumps"
dump() { # file, container, command run inside the container
  if docker exec "$2" sh -c "$3" > "$dumps/$1.tmp"; then
    mv "$dumps/$1.tmp" "$dumps/$1"
  else
    echo "dump of $1 failed" >&2; rm -f "$dumps/$1.tmp"; failed=1
  fi
}
{% for d in kopia_backup.dumps %}
dump {{ d.file | quote }} {{ d.container | quote }} {{ d.command | quote }}
{% endfor %}
{% endif %}
{% set ignores = kopia_backup.ignore | dict2items | rejectattr('value', 'none') | list %}
{% if ignores %}

# Ignore rules of a source, replaced as a whole (--clear-ignore runs after --add-ignore within one call).
# Kopia sorts the rules, so negations (!) cannot be relied on to come after the rule they override.
ignore() {
  local path=$1; shift
  kopia policy set "$path" --clear-ignore >/dev/null 2>&1 &&
    kopia policy set "$path" "${@/#/--add-ignore=}" >/dev/null 2>&1 ||
    { echo "setting the ignore rules of $path failed" >&2; failed=1; }
}
{% for i in ignores %}
ignore {{ i.key | quote }} {{ i.value | map('quote') | join(' ') }}
{% endfor %}
{% endif %}

for p in {{ kopia_backup.sources | map('quote') | join(' ') }}{{ ' "$etcd"' if kopia_backup.etcd_snapshot }}{{ ' "$dumps"' if kopia_backup.dumps }}; do
  [ -d "$p" ] && sources+=("$p")
done
kopia snapshot create "${sources[@]}" || failed=1
exit $failed