安装composer

wget http://curl.haxx.se/ca/cacert.pem

curl -sS https://getcomposer.org/installer | php -- --cafile=cacert.pem

安装protoc-gen-php

composer require "protocolbuffers/protoc-gen-php:dev-master"

如果网络差可以使用代理(* 转 http 代理）

proxychains4 composer require "protocolbuffers/protoc-gen-php:dev-master"