Logging helpers

helper.sh

# Where is this script on the system.
SCRIPT_PATH="$(dirname "${BASH_SOURCE[0]}")"
SCRIPT_DIR="$(realpath "${SCRIPT_PATH}")"
SCRIPT_LOG="${SCRIPT_DIR}/../../test-harness.log"

# There are subtle differences between macOS and Linux that need to be accounted for.
PLATFORM="$(uname -o)"

# Colours for easier reading.
COLOUR_GREY="$(tput setaf 248)"
COLOUR_BLUE="$(tput setaf 68)"
COLOUR_GREEN="$(tput setaf 118)"
COLOUR_END="$(tput setaf 248)"

# Log writes the passed string to the log file and standard out with timestamps.
function log() {
	_log_internal "${COLOUR_BLUE}${@}${COLOUR_END}"
}

# log_command executes the passed command, writing each log message from STDERR and
# STDOUT to the log file, with timestamps.
function log_command() {
	eval "$@" 2>&1 | while IFS= read -r line; do
		_log_internal "    ${COLOUR_GREEN}${line}${COLOUR_END}"
	done

	return $?
}

# _log_internal handles formatting and writing of passed log messages. This should only
# be called by other functions, and not the user.
function _log_internal() {
	date=$(date +"%Y-%m-%d %H:%M:%S" | tr -d '\n')

	# Ensure the correct flags are used for sed on macOS.
	SED="sed -e"
	if [ ${PLATFORM} == "Darwin" ]; then
		SED="sed -E"
	fi

	# The sed command is used here to strip any ANSI colour codes in the output but only
	# when writing to file.
	echo "${date} - ${@}" | tee >(${SED} $'s/\x1b\[[0-9;]*[mGKHF]//g' >> "${SCRIPT_LOG}")
}