docker-compose 不启动 postgres 图像

Question

我正在为 Django 应用程序创建 docker-compose 配置，Dockerfile 构建成功，但是当我组合它们时，django return 出现问题 -- 无法连接到 posgres。

我运行docker-compose run web bash,发现redis和posgres都连接不上

我的docker-compose.yml文件：

db:
  image: postgres:9.1
  environment:
    - POSTGRES_PASSWORD=mysecretpassword

redis:
    image: redis:2.8

web:
  links:
    - db
    - redis
  build: .
  volumes:
    - .:/workspace
  ports:
    - "8000:8000“
  command: python /workspace/BreadTripServer/webapps/manage.py runserver 0.0.0.0:8000 --settings=configs.local_default

我这样做时的错误信息 docker-compose up:

sudo docker-compose up
Recreating breadtrip_db_1...
Recreating breadtrip_redis_1...
Recreating breadtrip_web_1...
Attaching to breadtrip_redis_1, breadtrip_web_1
redis_1 | [1] 06 May 06:07:30.469 # Warning: no config file specified, using the default config. In order to specify a config file use redis-server /path/to/redis.conf

... 

redis_1 | [1] 06 May 06:07:30.490 # Server started, Redis version 2.8.19
redis_1 | [1] 06 May 06:07:30.490 # WARNING overcommit_memory is set to 0! Background save may fail under low memory condition. To fix this issue add 'vm.overcommit_memory = 1' to /etc/sysctl.conf and then reboot or run the command 'sysctl vm.overcommit_memory=1' for this to take effect.
redis_1 | [1] 06 May 06:07:30.490 # WARNING you have Transparent Huge Pages (THP) support enabled in your kernel. This will create latency and memory usage issues with Redis. To fix this issue run the command 'echo never > /sys/kernel/mm/transparent_hugepage/enabled' as root, and add it to your /etc/rc.local in order to retain the setting after a reboot. Redis must be restarted after THP is disabled.
redis_1 | [1] 06 May 06:07:30.491 # WARNING: The TCP backlog setting of 511 cannot be enforced because /proc/sys/net/core/somaxconn is set to the lower value of 128.
redis_1 | [1] 06 May 06:07:30.491 * DB loaded from disk: 0.000 seconds
redis_1 | [1] 06 May 06:07:30.491 * The server is now ready to accept connections on port 6379
web_1   | Traceback (most recent call last):
web_1   |   File "/workspace/BreadTripServer/webapps/manage.py", line 14, in <module>
web_1   |     execute_manager(settings)
web_1   |   File "/usr/local/lib/python2.7/dist-packages/django/core/management/__init__.py", line 438, in execute_manager
web_1   |     utility.execute()
web_1   |   File "/usr/local/lib/python2.7/dist-packages/django/core/management/__init__.py", line 379, in execute
web_1   |     self.fetch_command(subcommand).run_from_argv(self.argv)
web_1   |   File "/usr/local/lib/python2.7/dist-packages/django/core/management/base.py", line 191, in run_from_argv
web_1   |     self.execute(*args, **options.__dict__)
web_1   |   File "/usr/local/lib/python2.7/dist-packages/django/core/management/base.py", line 209, in execute
web_1   |     translation.activate('en-us')
web_1   |   File "/usr/local/lib/python2.7/dist-packages/django/utils/translation/__init__.py", line 100, in activate
web_1   |     return _trans.activate(language)
web_1   |   File "/usr/local/lib/python2.7/dist-packages/django/utils/translation/trans_real.py", line 202, in activate
web_1   |     _active.value = translation(language)
web_1   |   File "/usr/local/lib/python2.7/dist-packages/django/utils/translation/trans_real.py", line 185, in translation
web_1   |     default_translation = _fetch(settings.LANGUAGE_CODE)
web_1   |   File "/usr/local/lib/python2.7/dist-packages/django/utils/translation/trans_real.py", line 162, in _fetch
web_1   |     app = import_module(appname)
web_1   |   File "/usr/local/lib/python2.7/dist-packages/django/utils/importlib.py", line 35, in import_module
web_1   |     __import__(name)
web_1   |   File "/workspace/BreadTripServer/webapps/lib/haystack/__init__.py", line 83, in <module>
web_1   |     backend = load_backend(settings.HAYSTACK_SEARCH_ENGINE)
web_1   |   File "/workspace/BreadTripServer/webapps/lib/haystack/__init__.py", line 57, in load_backend
web_1   |     return importlib.import_module('haystack.backends.%s_backend' % backend_name)
web_1   |   File "/usr/local/lib/python2.7/dist-packages/django/utils/importlib.py", line 35, in import_module
web_1   |     __import__(name)
web_1   |   File "/workspace/BreadTripServer/webapps/lib/haystack/backends/__init__.py", line 6, in <module>
web_1   |     from django.db.models import Q
web_1   |   File "/usr/local/lib/python2.7/dist-packages/django/db/__init__.py", line 78, in <module>
web_1   |     connection = connections[DEFAULT_DB_ALIAS]
web_1   |   File "/usr/local/lib/python2.7/dist-packages/django/db/utils.py", line 94, in __getitem__
web_1   |     conn = backend.DatabaseWrapper(db, alias)
web_1   |   File "/usr/local/lib/python2.7/dist-packages/django/contrib/gis/db/backends/postgis/base.py", line 11, in __init__
web_1   |     self.ops = PostGISOperations(self)
web_1   |   File "/usr/local/lib/python2.7/dist-packages/django/contrib/gis/db/backends/postgis/operations.py", line 91, in __init__
web_1   |     vtup = self.postgis_version_tuple()
web_1   |   File "/usr/local/lib/python2.7/dist-packages/django/contrib/gis/db/backends/postgis/operations.py", line 445, in postgis_version_tuple
web_1   |     version = self.postgis_lib_version()
web_1   |   File "/usr/local/lib/python2.7/dist-packages/django/contrib/gis/db/backends/postgis/operations.py", line 425, in postgis_lib_version
web_1   |     return self._get_postgis_func('postgis_lib_version')
web_1   |   File "/usr/local/lib/python2.7/dist-packages/django/contrib/gis/db/backends/postgis/operations.py", line 406, in _get_postgis_func
web_1   |     cursor = self.connection._cursor()
web_1   |   File "/usr/local/lib/python2.7/dist-packages/django/db/backends/postgresql_psycopg2/base.py", line 140, in _cursor
web_1   |     self.connection = Database.connect(**conn_params)
web_1   |   File "/usr/local/lib/python2.7/dist-packages/psycopg2/__init__.py", line 179, in connect
web_1   |     connection_factory=connection_factory, async=async)
web_1   | psycopg2.OperationalError: could not connect to server: Connection refused
web_1   |   Is the server running on host "localhost" (::1) and accepting
web_1   |   TCP/IP connections on port 5432?
web_1   | could not connect to server: Connection refused
web_1   |   Is the server running on host "localhost" (127.0.0.1) and accepting
web_1   |   TCP/IP connections on port 5432?
web_1   | 
breadtrip_web_1 exited with code 1

更新：

因为我将 link 设置为其他图像，docker link 在主机 172.17.0.67 上编辑了 pg，我需要将 pg 主机设置为未提及的地址docker 的官方文档。（这个地址每次都会变，但是可以通过env获取）

现在，我遇到了另一个问题：

web_1   | Unknown command: 'runserver'
web_1   | Type 'manage.py help' for usage.
breadtrip_web_1 exited with code 1

如果我将命令 python /workspace/BreadTripServer/webapps/manage.py runserver 0.0.0.0:8000 --settings=configs.local_default 更改为 python /workspace/BreadTripServer/webapps/manage.py runserver，它可以正常工作，但我无法访问网页。

Answer 1

您的应用程序似乎正在 localhost 上查找数据库。它应该在主机 db 上寻找数据库（主机名将通过 link 参数添加到 /etc/hosts）。

Answer 2

在您的 BUILD 树中某处可能有一个名为 settings.py 的文件。您可以通过键入以下命令找到它：

find . -name settings.py

找到后，您需要编辑该文件。它看起来像这样：

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.postgresql_psycopg2', # Add 'postgresql_psycopg2', 'mysql', 'sqlite3' or 'oracle'.
        'NAME': 'mydb',                      # Or path to database file if using sqlite3.
        # The following settings are not used with sqlite3:
        'USER': 'myuser',
        'PASSWORD': 'password',
        'HOST': 'localhost',                      # Empty for localhost through domain sockets or           '127.0.0.1' for localhost through TCP.
        'PORT': '',                      # Set to empty string for default.
    }
}

看到 'localhost' 了吗？将其更改为 'db' （正如@Adrian 建议的那样），您将解决此问题。（好吧，你会继续下一个问题:-)）你应该把答案归功于 Adrian。

Answer 3

我遇到了这个问题，当我遇到这个 SO 答案时正在抓紧救命稻草：。

对我有用的解决方案是使用

终止所有 postgres 进程

sudo pkill postgres

Answer 4

我遇到了这个问题，这只是因为我使用的是 VPN。如果您正在使用类似 sshuttle 的功能，请将其关闭。

docker-compose 不启动 postgres 图像

docker-compose does not start postgres image

django

postgresql

docker

docker-compose