docker-compose.yml for using Memcached via PHP 7.1

structure

Docker/
  ├ docker-compose.yml
  └ phpapache/
    └ Dockerfile
    └ html/
      └ index.php

docker-compose.yml

version: '3'
services:
  web:
    container_name: myserver
    build:
      context: ./phpapache
    volumes:
      - ./phpapache/html:/var/www/html
    tty: true
    ports:
      - "80:80"

  memcached:
    container_name: mymemcached
    image: memcached:latest
    ports:
      - "11211:11211"

phpapache/Dockerfile

FROM php:7.1-apache
RUN apt-get update \
    && apt-get install -y libmemcached-dev zlib1g-dev \
    && pecl install memcached-3.0.4 \
    && docker-php-ext-enable memcached
CMD ["/usr/sbin/apache2ctl", "-D", "FOREGROUND"]

html/index.php

<?php                                                                                                                                                                                          
$mc = new Memcached();                                                             
$mc->addServer("mymemcached", 11211);                                              
$mc->add("key1", "value1");                                                        
$mc->add("key2", "value2");                                                        
$mc->add("key3", "value3");                                                        

echo "key1 : " . $mc->get("key1") . "\n";                                          
echo "key2 : " . $mc->get("key2") . "\n";                                          
echo "key3 : " . $mc->get("key3") . "\n";   

$ docker-composer up --build

Then access to http://localhost