Poor man's Telegram notifier

telegram.sh

#!/bin/bash
# Bash Import/Source script
# Prints/Sends start/error/end messages

set -o pipefail
set -o errtrace

# Have below variables set
TELEGRAM_BOT_TOKEN=''
TELEGRAM_CHAT_ID=''

script_name=`basename "$0"`

notify() {
    local    -r message_text="${@:1}"
    echo "$message_text"
    curl --silent "https://api.telegram.org/bot${TELEGRAM_BOT_TOKEN}/sendMessage?chat_id=${TELEGRAM_CHAT_ID}&text=${message_text}" 2>&1 > /dev/null
}

report_error() {
    declare  -a  return_codes=("${PIPESTATUS[@]}")
    local    -r  array_length="$((${#return_codes[@]}-1))"
    local    -r  return_code="${return_codes[array_length]}"
    local    -r  error_message="ERROR in ${script_name} at line ${BASH_LINENO[0]} command ${BASH_COMMAND} with exit code ${return_code}"
    notify $error_message
    exit 99
}

report_end() {
    local    -r  end_message="$script_name ended."
    notify  $end_message
}

notify "$script_name started."

trap report_error ERR
trap report_end EXIT

zample.sh

#!/bin/bash

. telegram.sh

echo `date --utc`
bash -c 'echo oops; exit 111'
echo `date --utc`
exit 0

# What we get on Telegram:
#  zample.sh started.
#  ERROR in zample.sh at line 6 command bash -c 'echo oops; exit 111' with exit code 111
#  zample.sh ended.