Question

我一直在尝试在docker容器中创建一个烧瓶应用程序。该应用程序在通过Flask开发服务器运行时非常有效，包括从网络上的其他计算机访问网页。

我一直在尝试为应用构建一个Docker容器。问题是我无法访问任何网页。我得到500个错误。

我的一些设置：

run.py

#!flask_v1/bin/python3
from app import app
app.run(debug=True, host='0.0.0.0')

其中flask_v1是virtualenv目录。

dockerfile

FROM python:3.4
COPY . /site
workdir /site
RUN pip install -r requirements.txt
ENV NAME sitename
CMD ["python", "./run.py"]

我从此版本中删除了 EXPOSE 5000 ，但是它出现了同样的问题。它最初被置于点线下。

requirements.txt

click==6.7
CouchDB==1.1
docutils==0.14
Flask==0.12.2
Flask-CouchDB==0.2.1
flask-dynamo==0.1.2
Flask-Login==0.4.0
Flask-WTF==0.14.2
itsdangerous==0.24
Jinja2==2.9.6
jmespath==0.9.3
MarkupSafe==1.0
python-dateutil==2.6.1
PyYAML==3.12
s3transfer==0.1.11
six==1.11.0
Werkzeug==0.12.2
WTForms==2.1

然后我运行build命令，如下所示（dockername替换为实际名称）：

docker build -t dockername .

构建完成，我按如下方式运行图像：

docker run -p 5000:5000 dockername

尝试连接到localhost：5000 / index（应用程序的'home'），或者只是localhost：5000，或127.0.0.1:5000/index，或[host_ip]：5000 / index，或者[container_ip]：5000 / index all产生了同样的错误：

Traceback (most recent call last):
  File "/usr/local/lib/python3.4/site-packages/flask/app.py", line 1997, in __call__
    return self.wsgi_app(environ, start_response)
  File "/usr/local/lib/python3.4/site-packages/flask/app.py", line 1985, in wsgi_app
    response = self.handle_exception(e)
  File "/usr/local/lib/python3.4/site-packages/flask/app.py", line 1540, in handle_exception
    reraise(exc_type, exc_value, tb)
  File "/usr/local/lib/python3.4/site-packages/flask/_compat.py", line 33, in reraise
    raise value
  File "/usr/local/lib/python3.4/site-packages/flask/app.py", line 1982, in wsgi_app
    response = self.full_dispatch_request()
  File "/usr/local/lib/python3.4/site-packages/flask/app.py", line 1614, in full_dispatch_request
    rv = self.handle_user_exception(e)
  File "/usr/local/lib/python3.4/site-packages/flask/app.py", line 1517, in handle_user_exception
    reraise(exc_type, exc_value, tb)
  File "/usr/local/lib/python3.4/site-packages/flask/_compat.py", line 33, in reraise
    raise value
  File "/usr/local/lib/python3.4/site-packages/flask/app.py", line 1610, in full_dispatch_request
    rv = self.preprocess_request()
  File "/usr/local/lib/python3.4/site-packages/flask/app.py", line 1831, in preprocess_request
    rv = func()
  File "/usr/local/lib/python3.4/site-packages/flaskext/couchdb.py", line 154, in request_start
    self.sync(current_app)
  File "/usr/local/lib/python3.4/site-packages/flaskext/couchdb.py", line 131, in sync
    if db_name not in server:
  File "/usr/local/lib/python3.4/site-packages/couchdb/client.py", line 96, in __contains__
    self.resource.head(name)
  File "/usr/local/lib/python3.4/site-packages/couchdb/http.py", line 549, in head
    return self._request('HEAD', path, headers=headers, **params)
  File "/usr/local/lib/python3.4/site-packages/couchdb/http.py", line 581, in _request
    credentials=self.credentials)
  File "/usr/local/lib/python3.4/site-packages/couchdb/http.py", line 289, in request
    conn = self.connection_pool.get(url)
  File "/usr/local/lib/python3.4/site-packages/couchdb/http.py", line 507, in get
    conn.connect()
  File "/usr/local/lib/python3.4/http/client.py", line 871, in connect
    self.timeout, self.source_address)
  File "/usr/local/lib/python3.4/socket.py", line 516, in create_connection
    raise err
  File "/usr/local/lib/python3.4/socket.py", line 507, in create_connection
    sock.connect(sa)
OSError: [Errno 99] Cannot assign requested address

在阅读了与此类似的其他一些stackoverflow问题后，我使用-d选项运行容器，并按如下方式访问容器：

docker exec -ti <container name> bash

进入内部后，使用curl和wget我尝试访问localhost：5000 / index。 Wget只丢了500个错误。 Curl返回Werkzeug页面（参见上面的错误转储），包括所有html格式。目录结构看起来很好

我知道我必须配置错误的东西。我只是看不出它是什么。该应用程序在Docker外部运行，在Docker中不会运行一次。我无法从容器内部访问页面告诉我一些关于设置的事情是不对的，但是我要么缺乏知道如何，要么拥有“木树林”时刻。请帮助一位亲戚。

Answer 1

如果查看错误，首先是应用程序异常。这意味着您在主机和容器内的绑定都可以正常工作。它与暴露的端口无关。

如果我们再看一下异常堆栈跟踪

File "/usr/local/lib/python3.4/site-packages/couchdb/http.py", line 289, in request
    conn = self.connection_pool.get(url)
  File "/usr/local/lib/python3.4/site-packages/couchdb/http.py", line 507, in get
    conn.connect()
  File "/usr/local/lib/python3.4/http/client.py", line 871, in connect
    self.timeout, self.source_address)

您正在连接到沙发数据库，并且该地址不正确，这就是抛出错误的原因。错误OSError: [Errno 99] Cannot assign requested address有点误导，但这是因为您无法连接到可能配置错误或根本无法运行的Couch DB服务

无法到达docker容器中的烧瓶app

run.py

dockerfile

requirements.txt

1 个答案: