我正在学习 docker 。我想在我的应用程序中添加缓存功能,并因此使用memcached。以下是我的docker-compose.yml文件
version: "3"
services:
app:
build: .
volumes:
- .:/project
command: 'rails s -b 0.0.0.0 -p 3000'
container_name: 'test_rails'
ports:
- 3000:3000
depends_on:
- database
links:
- memcached
database:
image: postgres:latest
volumes:
- ./data:/var/lib/postgresql/data
environment:
POSTGRES_USER: docker-user
POSTGRES_PASSWORD: docker-password
POSTGRES_DB: docker-db
memcached:
build:
context: .
dockerfile: Dockerfile.memcached
command: 'tail -f /dev/null'
当我尝试使用以下代码从
memcached
容器连接到app
容器内的memcached服务器时require 'dalli'
options = { :namespace => "app_v1", :compress => true }
dc = Dalli::Client.new('localhost:11211', options)
然后我变得低于错误
WARN -- : localhost:11211 failed (count: 0) Errno::EADDRNOTAVAIL: Cannot assign requested address - connect(2) for "localhost" port 11211
Dalli::RingError: No server available
from /usr/local/bundle/gems/dalli-2.7.10/lib/dalli/ring.rb:46:in `server_for_key'
from /usr/local/bundle/gems/dalli-2.7.10/lib/dalli/client.rb:367:in `perform'
from /usr/local/bundle/gems/dalli-2.7.10/lib/dalli/client.rb:130:in `set'
from (irb):4
from /usr/local/bin/irb:11:in `<main>'
有人可以帮助我理解和解决此问题。
最佳答案
您无法使用本地主机从另一个服务访问一个docker服务,因为每个服务都有自己的IP地址,就像自己的小型vm一样。使用服务名称而不是localhost,docker将使用目标服务的ip地址解析它,
`dc = Dalli::Client.new('memcached:11211', options)`