#!/usr/bin/env bash
# {{ ansible_managed }}
# Backup script for {{ item.src|default('stdin') }}
# Use this file to create a Backup and prune existing data with one execution.

pid="/var/run/restic_backup_{{  item.name | regex_replace('\'', '\'\\\'\'') }}.pid"
trap "rm -f $pid" SIGSEGV
trap "rm -f $pid" SIGINT

if [ -e $pid ]; then
  echo "Another version of this restic backup script is already running!"
   {% if item.mail_on_error is defined and item.mail_on_error == true %}
    mail -s "starting restic backup failed on {{ ansible_hostname }}" {{ item.mail_address }}  <<< "Another restic backup process is already running. We canceled starting a new restic backup script running at {{ ansible_hostname }} at $(date -u '+%Y-%m-%d %H:%M:%S').
      {%- if item.src is defined -%}
        {{ ' ' }}We tried to backup '{{ item.src }}'.
      {%- endif -%}
      {{ ' ' }}Please repair the restic-{{ item.name | replace(' ', '') }} job."
    {% endif %}
   exit # pid file exists, another instance is running, so now we politely exit
else
    echo $$ > $pid # pid file doesn't exit, create one and go on
fi
# your normal workflow here...


{% if item.disable_logging is defined and item.disable_logging %}
{% set backup_result_log, backup_output_log = "/dev/null", "/dev/null" %}
{% set forget_result_log, forget_output_log = "/dev/null", "/dev/null" %}
{% else %}
{% if (item.log_to_journald is defined and item.log_to_journald) %}
{% set backup_result_log, backup_output_log = "| systemd-cat -t " + item.name, "2>&1 | systemd-cat -t " + item.name %}
{% set forget_result_log, forget_output_log = "| systemd-cat -t " + item.name, "2>&1 | systemd-cat -t " + item.name %}
{% else %}
{% set backup_result_log, backup_output_log = ">> " + restic_log_dir + "/" + item.name + "-backup-result.log", " 2>&1 | tee " + restic_log_dir + "/" + item.name + "-backup-output.log" %}
{% set forget_result_log, forget_output_log = ">> " + restic_log_dir + "/" + item.name + "-forget-result.log", " 2>&1 | tee " + restic_log_dir + "/" + item.name + "-forget-output.log" %}
{% endif %}
{% endif %}

{% if restic__cache_config | bool -%}
  export XDG_CACHE_HOME={{ restic__cache_dir }}
{% endif %}

{% if restic__limit_cpu_usage | bool -%}
# Maximum number of CPUs used by restic is limited to {{ restic__max_cpus }}
export GOMAXPROCS={{ restic__max_cpus }}
{% endif %}

export RESTIC_REPOSITORY={{ restic_repos[item.repo].location }}
export RESTIC_PASSWORD='{{ restic_repos[item.repo].password | regex_replace('\'', '\'\\\'\'') }}'
BACKUP_NAME={{ item.name }}
{% if restic_repos[item.repo].aws_access_key is defined %}
export AWS_ACCESS_KEY_ID={{ restic_repos[item.repo].aws_access_key }}
{% endif %}
{% if restic_repos[item.repo].aws_secret_access_key is defined %}
export AWS_SECRET_ACCESS_KEY='{{ restic_repos[item.repo].aws_secret_access_key | regex_replace('\'', '\'\\\'\'') }}'
{% endif %}
{% if restic_repos[item.repo].aws_default_region is defined %}
export AWS_DEFAULT_REGION={{ restic_repos[item.repo].aws_default_region }}
{% endif %}
{% if restic_repos[item.repo].azure_account_name is defined %}
export AZURE_ACCOUNT_NAME={{ restic_repos[item.repo].azure_account_name }}
{% endif %}
{% if restic_repos[item.repo].azure_account_key is defined %}
export AZURE_ACCOUNT_KEY={{ restic_repos[item.repo].azure_account_key }}
{% endif %}
{% if restic_repos[item.repo].azure_account_sas is defined %}
export AZURE_ACCOUNT_SAS='{{ restic_repos[item.repo].azure_account_sas }}'
{% endif %}
{% if restic_repos[item.repo].azure_endpoint_suffix is defined %}
export AZURE_ENDPOINT_SUFFIX={{ restic_repos[item.repo].azure_endpoint_suffix }}
{% endif %}
{% if restic_repos[item.repo].b2_account_id is defined %}
export B2_ACCOUNT_ID={{ restic_repos[item.repo].b2_account_id }}
{% endif %}
{% if restic_repos[item.repo].b2_account_key is defined %}
export B2_ACCOUNT_KEY={{ restic_repos[item.repo].b2_account_key }}
{% endif %}
{% if item.src is defined  and item.src is string %}
BACKUP_SOURCE={{ item.src }}
{% endif %}
{% if item.src is defined  and item.src.__class__.__name__ =='list' %}
BACKUP_SOURCE='{{ item.src| join(' ') }}'
{% endif %}

{% if item.lvm is defined %}
# Set up functions for LVM.

function mount_opt_map {
    mount_type="$1"
    case "$mount_type" in
        xfs)
            echo "noatime,nouuid"
            ;;
        ext4)
            echo "noatime"
            ;;
        *)
            echo "noatime"
    esac
}

function prepare_vol {
    local path="$1"
    [ -d "$path" ] || path="$(dirname "$path")"
    if [ "$path" == '/' ] ; then
        mkdir -p /rootfs;
        newpath='/rootfs';
    else
        newpath="$path";
    fi

    {
        local source="$(findmnt -J -T ${path} | jq -r '.filesystems[0].source')"
        local target="$(findmnt -J -T ${path} | jq -r '.filesystems[0].target')"
        subdir=${path##$target}
        echo "Creating snapshot ..."
        lvcreate -y -L "${size:-10G}" -s -n "${source}_snap" "${source}"

        local tmpdir="$(mktemp -d)"
        local fs="$(lsblk -J --fs "$source" | jq -r '.blockdevices[0]|.fstype')"
        echo "Identified fstype: $fs; using opts $(mount_opt_map "$fs") ..."
        mount -t "$fs" \
              -o "$(mount_opt_map "$fs")" \
              --make-private \
              "${source}_snap" "${tmpdir}"

        mount --bind --make-private "${tmpdir}/${subdir}" "${newpath}"
    }
}

function cleanup_vol {
    local path="$1"
    [ -d "$path" ] || path="$(dirname "$path")"
    if [ "$path" == '/' ] ; then
        newpath='/rootfs';
    else
        newpath="$path";
    fi

    {
        local source="$(findmnt -v -J -T "${newpath}" | jq -r '.filesystems[]|.source' | grep '_snap$')"

        if ! grep -q '_snap$' <<< $source; then
            echo "Snapshot for ${path} could not be found (found: ${source}). Exiting!" && return 1;
        fi

        echo "Cleaning up mount ..."
        umount "${newpath}"

        echo "Cleaning up snapshot ..."
        umount "${source}"
        lvremove -y "${source}";
    }
}
{% endif %}

set -uxo pipefail
{#
  Define Tags
#}
{% macro tags(tags) -%}
  {% if tags is defined and (tags|length>0) %}{% for tag in tags %} --tag {{ tag }}{% endfor %}{% endif %}
{%- endmacro %}
{#
  Define Keeped Tags
#}
{% macro keep_tags(tags) -%}
  {% if tags is defined and (tags|length>0) %}{% for tag in tags %} --keep-tag {{ tag }}{% endfor %}{% endif %}
{%- endmacro %}
{#
  Define Hostname
#}
{% macro hostname(h) -%}
  {% if h is defined %} --hostname {{ h }}{% endif %}
{%- endmacro %}
{#
  Define stdin filename
#}
{% macro stdin_filename(n) -%}
  {% if n is defined %} --stdin-filename {{ n }}{% endif %}
{%- endmacro %}
{#
  Define paths
#}
{% macro paths(repo) -%}
{% if repo.src is defined and repo.src != None and (repo.src is not string)  %}{%for path in repo.src %} --path {{ path }}{% endfor %}{%elif repo.src is string %}--path {{repo.src}} {% else %} --path {{ repo.stdin_filename }}{% endif %}
{%- endmacro %}
{#
  Define retention pattern
#}
{% macro retention_pattern(repo) -%}
  {% if repo.keep_last is defined and repo.keep_last != None %}--keep-last {{ item.keep_last }}{% endif %} \
  {% if repo.keep_hourly is defined and repo.keep_hourly != None %}--keep-hourly {{ item.keep_hourly }}{% endif %} \
  {% if repo.keep_daily is defined and repo.keep_daily != None %}--keep-daily {{ item.keep_daily }}{% endif %} \
  {% if repo.keep_weekly is defined and repo.keep_weekly != None %}--keep-weekly {{ item.keep_weekly }}{% endif %} \
  {% if repo.keep_monthly is defined and repo.keep_monthly != None %}--keep-monthly {{ item.keep_monthly }}{% endif %} \
  {% if repo.keep_yearly is defined and repo.keep_yearly != None %}--keep-yearly {{ item.keep_yearly }}{% endif %} \
  {% if repo.keep_within is defined and repo.keep_within != None %}--keep-within {{ item.keep_within }}{% endif %} \
  {% if repo.keep_tag is defined and (repo.keep_tag|length>0) %}{{ keep_tags(repo.keep_tag) }}{% endif %}
{%- endmacro %}

{% macro exclude(exclude) %}
    {% if exclude.exclude_caches is defined and exclude.exclude_caches == true %}
        --exclude-caches \
    {% endif %}
    {% if exclude.exclude is defined %}
        {% for path in exclude.exclude %}
            --exclude {{ path }} \
        {% endfor %}
    {% endif %}
    {% if exclude.iexclude is defined %}
        {% for path in exclude.iexclude %}
            --iexclude {{ path }} \
        {% endfor %}
    {% endif %}
    {% if exclude.exclude_file is defined %}
        {% for path in exclude.exclude_file %}
            --exclude-file {{ path }} \
        {% endfor %}
    {% endif %}
    {% if exclude.exclude_if_present is defined %}
        {% for path in exclude.exclude_if_present %}
            --exclude-if-present {{ path }} \
        {% endfor %}
    {% endif %}
{% endmacro %}
{#
  Define backup commands
#}
if [[ -z ${CRON+x} ]]; then
  MODE_TAG="--tag manual"
else
  MODE_TAG="--tag cron"
fi

{% if item.stdin is defined and item.stdin == true %}
  {{ item.stdin_cmd }} | {{ restic_install_path }}/restic backup \
    --stdin $MODE_TAG \
    {{ tags(item.tags) }} \
    {{ stdin_filename(item.stdin_filename) }} \
    {% if item.exclude is defined %}{{ exclude(item.exclude) }}{% endif %} \
    $@ \
{% else %}
{
  {% if item.lvm is defined %}prepare_vol $BACKUP_SOURCE &&{% endif %}
  {{ restic_install_path }}/restic backup {% if item.lvm is defined and item.src == '/' %}/rootfs{% endif %}$BACKUP_SOURCE $MODE_TAG \
    {{ tags(item.tags) }} \
    {% if item.exclude is defined %}{{ exclude(item.exclude) }}{% endif %} \
    $@
} \
{% endif %} {{ backup_output_log }}

case $? in
    0)
        echo "$(date -u '+%Y-%m-%d %H:%M:%S') OK" {{ backup_result_log }}
        ;;
    3)
        echo "$(date -u '+%Y-%m-%d %H:%M:%S') WARNING" {{ backup_result_log }}
        ;;
    *)
        echo "$(date -u '+%Y-%m-%d %H:%M:%S') ERROR" {{ backup_result_log }}
    {% if item.mail_on_error is defined and item.mail_on_error == true %}
    mail -s "restic backup failed on {{ ansible_hostname }}" {{ item.mail_address }}  <<< "Something went wrong while running restic backup script running at {{ ansible_hostname }} at $(date -u '+%Y-%m-%d %H:%M:%S').
      {%- if item.src is defined -%}
        {{ ' ' }}We tried to backup '{{ item.src }}'.
      {%- endif -%}
      {{ ' ' }}Please repair the restic-{{ item.name | replace(' ', '') }} job."
{% endif %}
esac

{% if item.lvm is defined %}
    cleanup_vol $BACKUP_SOURCE
{% endif %}


{#
  Define stdin forget commands
#}
{{ restic_install_path }}/restic forget {{ paths(item) }} {{ retention_pattern(item) }} {% if item.prune is defined and item.prune == true %}--prune{% endif %} {{ forget_output_log }}
if [[ $? -eq 0 ]]
then
    echo "$(date -u '+%Y-%m-%d %H:%M:%S') OK" {{ forget_result_log }}
    {% if item.monitoring_call is defined %}
    {{ item.monitoring_call }}
    {% endif %}
else
    echo "$(date -u '+%Y-%m-%d %H:%M:%S') ERROR" {{ forget_result_log }}
    {% if item.mail_on_error is defined and item.mail_on_error == true %}
    mail -s "restic backup failed on {{ ansible_hostname }}" {{ item.mail_address }}  <<< "Something went wrong while running restic backup script running at {{ ansible_hostname }} at $(date -u '+%Y-%m-%d %H:%M:%S').
      {%- if item.src is defined -%}
        {{ ' ' }}We tried to backup '{{ item.src }}'.
      {%- endif -%}
      {{ ' ' }}Please repair the restic-{{ item.name | replace(' ', '') }} job."
    {% endif %}
fi
rm -f $pid # remove pid file just before exiting
exit