#!/usr/bin/env bash set -euo pipefail VERSION="$1" # ensure dir cd -P -- "$(dirname -- "${BASH_SOURCE[0]}")/.." DOWNLOAD_URL='https://dgiot-dev-1306147891.cos.ap-nanjing.myqcloud.com' download() { wget ${DOWNLOAD_URL}/${VERSION}/rebar3 } # get the version number from the second line of the escript # because command `rebar3 -v` tries to load rebar.config # which is slow and may print some logs version() { head -n 2 ./rebar3 | tail -n 1 | tr ' ' '\n' | grep -E '^.+-emqx-.+' } if [ -f 'rebar3' ] && [ "$(version)" = "$VERSION" ]; then exit 0 fi download chmod +x ./rebar3