Helper script to check availability of a set of Gnosis RPC endpoints

check-gnosis-chain-head.sh

#!/usr/bin/env bash

# exit on errors, undefined variables, ensure errors in pipes are not hidden
set -Eeuo pipefail

do_curl() {
	local endpoint="${1}"
	local start end timing
	start="$(date +%s%3N)"

	curl \
		-s \
		-m 10000 \
		-H "Content-Type: application/json" \
		-X POST \
		--data '{"method":"eth_blockNumber","params":[],"id":113,"jsonrpc":"2.0"}' \
		"${endpoint}" | \
	jq -r '.result' 2>/dev/null || echo ""

  end="$(date +%s%3N)"
	timing=$((end-start))

	echo >&2 "Checking ${endpoint} took ${timing} milliseconds"
}

hex_to_number() {
	local input="${1:-}"

	if [ -z "${input}" ]; then
		echo "FAILED"
	else
		printf '%d' $((16#${input#0x}))
	fi
}

declare response_main response_pp response_ankr

echo ""

response_main="$(do_curl "https://rpc.gnosischain.com/")"
response_pp="$(do_curl "https://provider-proxy.hoprnet.workers.dev/xdai_mainnet")"
response_ankr="$(do_curl "https://rpc.ankr.com/gnosis")"

echo ""
echo "Gnosis Chain Latest Block #"
echo "---------------------------"
echo -e "Main:\t\t   $(hex_to_number ${response_main})"
echo -e "Ankr:\t\t   $(hex_to_number ${response_ankr})"
echo -e "Provider Proxy:\t   $(hex_to_number ${response_pp})"
echo ""