Add ticker script

tick

@@ -0,0 +1,165 @@
+#! /bin/bash
+#
+# tick
+# A program to get the price of a symbol from Binance
+# Copyright (C) 2021 Vintage Salt <rehashedsalt@cock.li>
+#
+# Distributed under terms of the MIT license.
+#
+set -e
+
+# Read-only set-once variables
+declare -r _name="$(basename -- "$0")"
+# Options
+declare -i _opthelp
+declare -i _optverbose
+declare -i _optcolor
+declare _optsymbol
+# Working variables
+declare -a _args
+declare _return
+
+# Helper functions
+log() {
+	# Print a line to the terminal if _optverbose is greater than $2
+	# $2 defaults to 0
+	# loglevel 0: Daily-use messages
+	# loglevel 1: Detailed but not quite debugging
+	# loglevel 2: Definitely debugging
+	[ -z "$1" ] && return 1
+	if (( _optverbose >= ${2:-0} )); then
+		printf "%s\\n" "$1"
+	fi
+}
+warn() {
+	# Print a yellow line to the terminal, respecting _optverbose
+	[ -z "$1" ] && return 1
+	if (( _optverbose >= ${2:-0} )); then
+		if [ -t 1 ]; then
+			printf "\\e[33m%s\\e[0m\\n" "$1"
+		else
+			printf "WARN: %s\\n" "$1"
+		fi
+	fi
+}
+error() {
+	# Print a red line to the terminal, exit if $2 is specified
+	[ -z "$1" ] && return 1
+	if [ -t 2 ]; then
+		printf "\\e[31m%s\\e[0m\\n" "$1" 1>&2
+	else
+		printf "ERROR: %s\\n" "$1" 1>&2
+	fi
+	[ -z "$2" ] && return
+	exit "${2:-1}"
+}
+has() {
+	# Parse out all arguments and try to find them in path
+	# If an argument cannot be found, set _return and fail
+	for prog in "$@"; do
+		if ! command -v "$prog" > /dev/null 2>&1; then
+			_return="$prog"
+			return 1
+		fi
+	done
+	return 0
+}
+
+# Core program functions
+printhelp() {
+	cat << EOF
+Usage: $_name [OPTION]... SYMBOL
+Get the 24hr price change for a particular symbol from Binance
+
+  -c			Add color to the output
+  -d SYMBOL		Change the symbol displayed. Useful for comparisons against USDC
+			and other stablecoins
+  -h			Print this help text
+  -v			Print more status messages. Stacks
+
+Copyright (c) 2021 rehashedsalt@cock.li
+Licensed under the MIT license
+EOF
+}
+getprice() {
+	# Get the price of a coin from Binance
+	[ -z "$1" ] && return 1
+	symbol="$1"
+	result="$(curl -sL "https://api.binance.com/api/v3/ticker/24hr?symbol=$symbol")"
+	# Test to see if we got an error
+	if echo "$result" | jq '.code' -e > /dev/null 2>&1; then
+		code="$(echo "$result" | jq -re '.code')"
+		msg="$(echo "$result" | jq -re '.msg')"
+		error "Error $code: $msg" 51
+	fi
+	# Parse out the data
+	if [ -n "$_optsymbol" ]; then
+		symbol="$_optsymbol"
+	else
+		symbol="$(echo "$result" | jq -re '.symbol')"
+	fi
+	price="$(echo "$result" | jq -re '.priceChangePercent')"
+	if [ -n "$_optcolor" ]; then
+		if [[ "$price" == -* ]]; then
+			price="\e[31m$price\e[0m"
+		else
+			price="\e[32m$price\e[0m"
+		fi
+	fi
+	printf "$symbol $price\n"
+}
+
+# Main
+main() {
+	# Parse out arguments
+	while [ -n "$1" ]; do
+		# Parse out flags
+		while getopts ":cd:hv" opt; do
+			case $opt in
+				c)
+					_optcolor=1
+					;;
+				d)
+					_optsymbol="$OPTARG"
+					;;
+				h)
+					_opthelp=1
+					;;
+				v)
+					_optverbose+=1
+					;;
+				:)
+					error "Option requires argument: -$OPTARG" 2
+					;;
+				*)
+					error "Invalid option: -$OPTARG" 2
+					;;
+			esac
+		done
+		# Store arguments
+		shift $((OPTIND - 1))
+		if [ -n "$1" ]; then
+			_args+=("$1")
+			shift
+		fi
+		unset OPTIND
+	done
+	# Early hook for help
+	[ -n "$_opthelp" ] && printhelp && exit 0
+	# Validate critical options
+	if [ -z "${_args[*]}" ]; then
+		error "No symbol specified" 50
+	fi
+	# Validate core program dependencies
+	log "Validating dependencies" 2
+	if ! has basename curl jq; then
+		error "Failed to find program: $_return" 1
+	fi
+
+	# Do the do
+	getprice "${_args[0]}"
+	exit 0
+}
+
+main "$@"
+