Although php offical image has provided docker-php-ext-installer to help user install php extension, we still need to build some extension by ourself, because it hasn't include all extensions,such like memcache.
I use https://github.com/websupport-sk/pecl-memcache/archive/php7.zip to build memcache for php7
#All enabled extensions:
[PHP Modules] Core ctype curl date dom fileinfo filter gd hash iconv json ldap libxml mbstring mcrypt memcache mysqli mysqlnd openssl pcre PDO pdo_mysql pdo_sqlite Phar posix readline Reflection session SimpleXML SPL sqlite3 standard tokenizer xml xmlreader xmlwriter zip zlib [Zend Modules]
##Other important information