view pm2 log files through the bunyan log viewer

logview

#!/usr/bin/env bash

shopt -s extglob
set -o errtrace
#set -o errexit
set +o noclobber

# Defaults {{{
NOOP=
VERBOSE=${VERBOSE:0}
LOGVIEW_OPTS=%{LOGVIEW_OPTS:=}

FOLLOW=--nostream
TAIL=15
LOGPAGER=0
LOGCOLOR=--color
LOGTIME=-L
LOGFORMAT="--output short"
LOGLEVEL=${LOGLEVEL:=}
LOGFILTER=
# Defaults }}}

# DO NOT MODIFY ANYTHING AFTER THIS LINE ###############################################################

# General variables
SUBSYSTEM=
VERSION=1.0.0

# tracing and messages {{{
function trace()   { [[ $VERBOSE == 2 ]] && echo -e "Trace: $@" >&2; }
function verbose() { [[ $VERBOSE == 1 ]] && echo -e "$@"; }
function warn()    { echo -e "\033[33mWarning: $@\033[0m"; }
function error()   { echo -e "\033[1;31mError: $@\033[0m" >&2; }
function die()     { error "$1" ; exit ${2:-1} ; }
function die_on_error() { local status=$?; [[ $status != 0 ]] && die "$@, Error: $status" $status || return 0; }
# }}}

# Arguments {{{

function usage() { # {{{2
  echo "$(basename $0) [options] [subsystem|pm2 id]"
  echo "  View and Interpret logs for the given subsystem"
  echo "  Subsystems can be: config, line or line_connector, pnp or pnp_provider,"
  echo "                     pureconnect or pureconnect_connector."
  echo "  Subsystems can also be mentioned by their pm2 id."
  echo "  "
  echo "  Options below can also be set in the environment variable LOGVIEW_OPTS. Example:"
  echo "  export LOGVIEW_OPTS=\"--follow --more --local --short\""
  echo "  "
  echo "  Options are:"
  echo " --condition CONDITION, --filter CONDITION, -c CONDITION"
  echo "   Runs each log message through the condition and"
  echo "   only show those that return truish. E.g.:"
  echo "     -c 'this.pid == 123'"
  echo "     -c 'this.level == DEBUG'"
  echo "     -c 'this.msg.indexOf("boom") != -1'"
  echo "   \"CONDITION\" must be legal JS code. \`this\` holds the log record."
  echo "   The TRACE, DEBUG, ... FATAL values are defined to help with "
  echo "   comparing \`this.level\`."
  echo " --level LEVEL"
  echo "   Shows only messages at or above the specified level."
  echo "   \"LEVEL\" can be a level name or a numeric value."
  echo " --color"
  echo "   Colorizes the output (Default)."
  echo " --no-color"
  echo "   Does not colorize the output."
  echo " --follow, --tail, -f  "
  echo "   Follows the log file like \`tail -f\`."
  echo " --no-follow, --no-stream, --nostream"
  echo "   Does not follow the log file."
  echo " --lines LINES"
  echo "   Shows the last \"LINES\" lines of the log."
  echo " --pager, --more  "
  echo "   Pauses at the end of every page."
  echo "   Pipes output into \$PAGER, less, or more"
  echo " --no-pager, --no-more  "
  echo "   Does not Pause at the end of every page."
  echo " --local, --localtime, -L"
  echo "   Shows timestamps to the local time of this machine (Default)."
  echo " --utc"
  echo "   Shows timestamps in UTC"
  echo " --long"
  echo "   shows more information for each log entry."
  echo " --short"
  echo "   shows less information for each log entry (Default)."

  echo " --help  "
  echo "   Prints some help on the output."
  echo " --quiet  "
  echo "   Runs the script as silently as possible."
  echo " --noop, --dry-run, --dryrun  "
  echo "   Does not run any command that would change the state of the OS."
  echo "   Used with \`-v -v\` (yes, -v twice), it will show the actual "
  echo "   command it would execute."
  echo " --verbose  "
  echo "   Runs the script verbosely."
  echo " --version, -V  "
  echo "   Shows the version of this application."
  echo " --yes, --assumeyes, -y  "
  echo "   Answers yes to any questions automatically."
} # 2}}}

function parse_args() { # {{{2
  local status=0

  while (( "$#" )); do
    trace "Parsing option: $1"
    # Replace --parm=arg with --parm arg
    [[ $1 == --*=* ]] && set -- "${1%%=*}" "${1#*=}" "${@:2}"
    case $1 in
      # GENERAL Stuff
      -c|--condition|--filter)
        [[ -z $2 || ${2:0:1} == '-' ]] && die "Argument for option $1 is missing"
        LOGFILTER="-c '$2'"
        shift
        ;;
      --color)
        LOGCOLOR="--color"
        ;;
      --no-color|--no_color)
        LOGCOLOR="--no-color"
        ;;
      -f|--follow|--tail)
        FOLLOW=
        ;;
      --lines)
        [[ -z $2 || ${2:0:1} == '-' ]] && die "Argument for option $1 is missing"
        TAIL=$2
        shift
        ;;
      --no-follow|--no-stream|--nostream)
        FOLLOW="--nostream"
        ;;
      --pager|--more)
        LOGPAGER=1
        ;;
      --no-pager|--no-more)
        LOGPAGER=0
        ;;
      -L|--local|--localtime|--local_time|--local-time)
        LOGTIME=-L
        ;;
      --utc|--UTC)
        LOGTIME=
        ;;
      -l|--level)
        [[ -z $2 || ${2:0:1} == '-' ]] && die "Argument for option $1 is missing"
        LOGLEVEL="--level $2"
        shift
        ;;
      --long)
        LOGFORMAT="--output long"
        ;;
      --short)
        LOGFORMAT="--output short"
        ;;

      # Standard options
      -h|-\?|--help)
       usage
       exit 0
       ;;
      --noop|--dry_run|--dry-run)
        warn "This program will execute in dry mode, your system will not be modified"
        NOOP=:
        ;;
      --quiet)
        VERBOSE=0
        ;;
      -v|--verbose)
        VERBOSE=$((VERBOSE + 1))
        ;;
      --version|-V)
        echo "$(basename $0) version $VERSION"
        exit 0
        ;;
      -?*) # Invalid options
        warn "Unknown option $1 will be ignored"
        ;;
      --) # Force end of options
        shift
        break
        ;;
      *)  # End of options
        ARGS+=( "$1" )
        break
        ;;
    esac
    shift
  done

  # Set all positional arguments back in the proper order
  eval set -- "${ARGS[@]}"

  # Validations
  trace "$# Positional arguments: $@"
  [[ $# < 1 ]] && die "Missing subsystem name or id"
  SUBSYSTEM=$1

  return 0
} # 2}}}

# }}}

function main() { # {{{
  parse_args "$@" ; status=$? && [[ $status != 0 ]] && die "Failed to parse command line, error: $status" $status

  # Seems like --pager does not work with bunyan, so let's DIY!!!
  if [[ $LOGPAGER == 1 ]]; then
    if command -v less; then
      LOGPAGER=${PAGER:-less}
    else
      LOGPAGER=${PAGER:-more}
    fi
    trace "pm2 logs --raw --lines=$TAIL $FOLLOW $SUBSYSTEM | bunyan $LOGCOLOR $LOGTIME $LOGLEVEL $LOGFILER $LOGFORMAT | $LOGPAGER"
    $NOOP pm2 logs --raw --lines=$TAIL $FOLLOW $SUBSYSTEM | bunyan $LOGCOLOR $LOGTIME $LOGLEVEL $LOGFILER $LOGFORMAT | $LOGPAGER
  else
    trace "pm2 logs --raw --lines=$TAIL $FOLLOW $SUBSYSTEM | bunyan $LOGCOLOR $LOGTIME $LOGLEVEL $LOGFILER $LOGFORMAT"
    $NOOP pm2 logs --raw --lines=$TAIL $FOLLOW $SUBSYSTEM | bunyan $LOGCOLOR $LOGTIME $LOGLEVEL $LOGFILER $LOGFORMAT
  fi
  die_on_error "Failed to view log $SUBSYSTEM"

  exit 0
} # }}}

main "$@"