django - docker-compose 不启动 postgres 图像

Question

我正在为一个 django 应用程序创建一个 docker-compose 配置，Dockerfile 构建成功，但是当我组合它们时，django 返回一个问题——无法连接到 posgres。

我运行docker-compose run web bash，发现redis和posgres都无法连接。

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

docker-compose up 时的错误信息:

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:

因为我设置了指向其他图像的链接，docker 链接了主机 172.17.0.67 上的 pg，我需要将 pg 主机设置为 docker 官方文档中未提及的那个地址。 (这个地址每次都会改变，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，它工作正常，只是我无法访问网页。

Answer 1

看起来您的应用程序正在 localhost 上寻找数据库。它应该在主机 db 上查找数据库(主机名将通过链接参数添加到 /etc/hosts)。