Add borgmatic-wrapper script

usr/local/jilits/borgmatic-wrapper.sh

@@ -0,0 +1,148 @@
+#!/usr/bin/env bash
+
+# Performs borgmatic backups and checks, given that
+# enough time has elapsed since the last one performed.
+# cerberus, 2022-02-03-1
+
+set -o pipefail
+
+[ -f /opt/borg/bin/borg ] && borg=/opt/borg/bin/borg || borg="$(command -v borg)"
+[ -f /opt/borg/bin/borgmatic ] && borgmatic=/opt/borg/bin/borgmatic || borgmatic="$(command -v borgmatic)"
+
+export LOG_FILE="/var/log/borgmatic-wrapper.log"
+export STATE_DIR="/var/tmp/borgmatic-wrapper"
+LIB_DIR="${LIB_DIR:-/usr/local/jilits}"
+
+script_name="$(basename -- "$0")"
+max_minutes_since_last_backup=""
+max_minutes_since_last_check=720
+
+. "$LIB_DIR/libverbosity.sh" || exit 127
+. "$LIB_DIR/libcommon.sh" || exit 127
+. "$LIB_DIR/libdatatype.sh" || exit 127
+. "$LIB_DIR/libdatetime.sh" || exit 127
+. "$LIB_DIR/libstate.sh" || exit 127
+
+eggsit() {
+    rc=$?
+    [ $rc -eq 0 ] && echlog "Script exiting ($rc)..."
+    [ $rc -ne 0 ] && errlog "Script exiting ($rc)..."
+    exit $rc
+}
+trap "eggsit" EXIT
+
+get_last_backup_ts() {
+    local ts state_ttl="$((6 * 60 * 60))"
+    ts="$(get_state CachedLastBackupTimestamp)"
+
+    if [ -n "$ts" ]; then
+        echo "$ts"
+        return 0
+    fi
+
+    ts="$(sudo "$borgmatic" list --last 1 --successful --json | jq -r '.[0].archives[0].start')"
+    set_state CachedLastBackupTimestamp "$ts" "$state_ttl"
+    echo "$ts"
+}
+
+minutes_since_last_backup() {
+    local ue
+    ue="$(dt_to_ue "$(get_last_backup_ts)")"
+    echo "$((($(current_ue) - ue) / 60))"
+}
+
+remote_is_online() {
+    local host port
+    host="$(cut -d: -f1 <<<"$1")"
+    port="$(cut -d: -f2 <<<"$1")"
+    nc -zvw1 "${host:?Missing remote host}" "${port:?Missing remote port}" | tee -a "$LOG_FILE" >/dev/null
+}
+
+perform_backup() {
+    echlog "Running backup."
+
+    rm_state CachedLastBackupTimestamp
+    rm_state LastBackupPrettyTimestamp
+
+    "$borgmatic" create --files --stats --verbosity 2 --syslog-verbosity -1 2>&1 | tee -a "$LOG_FILE" || return 1
+    set_state LastBackupPrettyTimestamp "$(dt_to_pretty "$(get_last_backup_ts)")" "$((4 * 60 * 60))"
+
+    "$borgmatic" prune --files --stats --verbosity 2 --syslog-verbosity -1 2>&1 | tee -a "$LOG_FILE" || return 2
+}
+
+perform_check() {
+    echlog "Running check."
+
+    rm_state LastCheckUnixEpoch
+
+    "$borgmatic" check --progress --verbosity 2 --syslog-verbosity -1 2>&1 | tee -a "$LOG_FILE" || return 1
+    set_state LastCheckUnixEpoch "$(current_ue)" "$((24 * 60 * 60))"
+}
+
+function usage() {
+    echo "Usage: $script_name [OPTIONS]"
+    echo
+    echo "Options:"
+    echo "  -h              Display help."
+    echo "  -b [MINUTES]    Max minutes since last backup. "
+    echo "  -c [MINUTES]    Max minutes since last check."
+    echo "  -r [HOST:PORT]  Ensure remote is online before running actions."
+}
+
+while getopts ":b:c:r:h" arg; do
+    case $arg in
+    b) max_minutes_since_last_backup=$OPTARG ;;
+    c) max_minutes_since_last_check=$OPTARG ;;
+    r) remote_host_port=$OPTARG ;;
+    h)
+        usage
+        exit 0
+        ;;
+    :)
+        echo "$script_name: Must supply a value with -$OPTARG." >&2
+        usage
+        exit 1
+        ;;
+    ?)
+        echo "Invalid option: -${OPTARG}."
+        echo
+        usage
+        exit 2
+        ;;
+    esac
+done
+
+rotlog 10000000
+
+if ! is_int "$max_minutes_since_last_backup"; then
+    usage
+    echlog
+    echxit "ERROR: Invalid or unset value for argument -b: '$max_minutes_since_last_backup'" 2
+fi
+
+if ! im_root; then
+    echxit "ERROR: This script must be run as root" 1
+elif ! command -v jq >/dev/null; then
+    echxit "ERROR: jq not installed" 3
+elif pgrep -f "$borg" >/dev/null; then
+    echxit "ERROR: Borg seems to be active already" 11
+elif [ -n "$remote_host_port" ]; then
+    if ! remote_is_online "$remote_host_port"; then
+        echxit "ERROR: Unable to reach $remote_host_port" 12
+    fi
+fi
+
+echlog "The last backup was carried out $(minutes_since_last_backup) minutes ago (>=$max_minutes_since_last_backup)."
+if [[ "$(minutes_since_last_backup)" -ge "$max_minutes_since_last_backup" ]]; then
+    perform_backup || echxit "ERROR: Backup returned errors" 21
+fi
+
+last_check_unixepoch="$(get_state LastCheckUnixEpoch)" || last_check_unixepoch=0
+minutes_since_last_check="$((($(current_ue) - last_check_unixepoch) / 60))"
+echo "The last check was carried out $minutes_since_last_check minutes ago (>=$max_minutes_since_last_check)." | tee -a "$LOG_FILE"
+
+if [[ "$minutes_since_last_check" -ge "$max_minutes_since_last_check" ]]; then
+    perform_check || echxit "ERROR: Check returned errors" 21
+fi
+
+echo "Script finished."

usr/local/jilits/libcommon.sh

@@ -0,0 +1,5 @@
+#!/bin/bash
+
+im_root() {
+    [ "$EUID" -eq 0 ] || return 1
+}

usr/local/jilits/libdatatype.sh

@@ -0,0 +1,9 @@
+#!/bin/bash
+
+is_int() {
+    [[ $1 =~ ^[0-9]+$ ]] || return 1
+}
+
+is_float() {
+    [[ $1 =~ ^[0-9]+(\.[0-9]+)*$ ]] || return 1
+}

usr/local/jilits/libdatetime.sh

@@ -0,0 +1,13 @@
+#!/bin/bash
+
+current_ue() {
+    date +%s
+}
+
+dt_to_ue() {
+    date --date="${1:?Datetime not set}" +%s
+}
+
+dt_to_pretty() {
+    date --date="${1:?Datetime not set}" +"%Y-%m-%d %H:%M:%S"
+}

usr/local/jilits/libstate.sh

@@ -0,0 +1,102 @@
+#!/bin/bash
+
+# Make sure the state directory exists and create it if not
+ensure_state_dir() {
+    local state_dir="${STATE_DIR:?}"
+
+    if ! [ -d "$(dirname "$state_dir")" ]; then
+        errlog "ERROR: Parent directory of STATE_DIR '$state_dir' doesn't exist."
+        return 1
+    elif ! [ -d "$state_dir" ]; then
+        if ! mkdir "$state_dir"; then
+            errlog "ERROR: Failed to create STATE_DIR '$state_dir'."
+            return 2
+        fi
+    fi
+}
+
+# Get the configured TTL for a state key
+get_state_ttl() {
+    local state_file="${1:?Missing state file}"
+    local ttl_file="$state_file.ttl"
+    local state_ttl
+
+    state_ttl="$(cat "$ttl_file" 2>/dev/null)"
+
+    if ! is_int "$state_ttl"; then
+        errlog "WARN: Invalid value '$state_ttl' in '$ttl_file'. Assuming value 0."
+        state_ttl=0
+    fi
+
+    echo "$state_ttl"
+}
+
+# Get the age of a state key
+get_state_age() {
+    local state_file="${1:?Missing state file}"
+    local state_mod
+
+    state_mod="$(stat -c%Y "$state_file")"
+    echo "$(($(current_ue) - state_mod))"
+}
+
+# Check if a state has expired
+state_is_expired() {
+    local state_file="${1:?Missing state file}"
+    local state_ttl state_mod
+
+    state_ttl="$(get_state_ttl "$state_file")"
+    [ "$state_ttl" -eq 0 ] && return 1
+    [ "$(get_state_age "$state_file")" -gt "$state_ttl" ] && return 0
+}
+
+# Remove a state
+rm_state() {
+    local key="${1:?Missing key}"
+    local state_file="$STATE_DIR/$key"
+    local ttl_file="$state_file.ttl"
+    rm "$state_file" "$ttl_file"
+}
+
+# Check if a state key name is valid
+state_key_is_valid() {
+    local key="${1:?Missing key}" regex="^([0-9]|[a-z]|[A-Z]|-)*$"
+
+    if ! [[ "$key" =~ $regex ]]; then
+        errlog "ERROR: Key '$key' doesn't match regex '$regex'."
+        return 1
+    fi
+}
+
+# Write a value to a state key and optionally set a TTL
+set_state() {
+    local key="${1:?Missing key}" value="$2" ttl="${3:-0}"
+    local state_file="$STATE_DIR/$key"
+    local ttl_file="$state_file.ttl"
+
+    state_key_is_valid "$key" || return 1
+    ensure_state_dir || return 2
+
+    echo "$value" >"$state_file"
+    echo "$ttl" >"$ttl_file"
+}
+
+# Read a value from a state key
+get_state() {
+    local key="${1:?Missing key}"
+    local state_file="$STATE_DIR/$key"
+
+    state_key_is_valid "$key" || return 1
+    ensure_state_dir || return 2
+
+    if ! [ -f "$state_file" ]; then
+        errlog "WARN: State file doesn't exist: '$state_file'"
+        return 3
+    elif state_is_expired "$state_file"; then
+        errlog "WARN: State file has expired: '$state_file'"
+        rm_state "$key"
+        return 4
+    fi
+
+    cat "$state_file"
+}

usr/local/jilits/libverbosity.sh

@@ -0,0 +1,62 @@
+#!/bin/bash
+
+# Write to log
+wrlog() {
+    echo "$1" >>"${LOG_FILE:?}"
+}
+
+# Write to stdout/stderr and log
+echlog() {
+    local dt
+    dt="$(date +"%Y-%m-%dT%H:%M:%S")"
+
+    if [ -z "$1" ] && [ -z "$2" ]; then
+        echo ""
+        wrlog ""
+    elif [ -n "$1" ]; then
+        echo "$dt $1"
+        wrlog "$dt $1"
+    elif [ -n "$2" ]; then
+        echo "$dt $2" 1>&2
+        wrlog "$dt $2"
+    fi
+}
+
+# Write to stderr
+errlog() {
+    echlog "" "$1"
+}
+
+# Rotate the log file
+# TODO: Implement support for multiple rollovers and bz2 compression
+rotlog() {
+    local filesize maxsize="${1:-10000000}"
+
+    if ! [ -f "$LOG_FILE" ]; then
+        echlog "File doesn't exist: '$LOG_FILE'"
+        return 0
+    fi
+
+    filesize="$(stat -c%s "$LOG_FILE")"
+
+    if ((filesize > maxsize)); then
+        echlog "Rotating log ($filesize > $maxsize)"
+        [ -f "$LOG_FILE.0" ] && rm "$LOG_FILE.0"
+        mv "$LOG_FILE" "$LOG_FILE.0"
+    fi
+}
+
+# Echo $1 and exit with code $2
+echxit() {
+    if [ "$2" -eq 0 ]; then
+        echlog "$1"
+        exit "$2"
+    elif [ "$2" -gt 0 ]; then
+        errlog "$1"
+        exit "$2"
+    fi
+
+    errlog "$1"
+    errlog "Invalid exit code specified to echxit"
+    exit 255
+}