Question

我需要在Docker中实现一个简单的python应用程序。我按照说明操作：https://docs.docker.com/get-started/part2/#dockerfile

我运行这样的构建命令：

sudo docker build -t sender .

我的requirements.txt看起来如下：

 pika==0.11.2

Dockerfile包含以下内容（上述教程中的代码）

# Use an official Python runtime as a parent image
FROM python:3

# Set the working directory to /app
WORKDIR /app

# Copy the current directory contents into the container at /app
ADD . /app

# Install any needed packages specified in requirements.txt
RUN pip install --trusted-host pypi.python.org -r requirements.txt

# Make port 80 available to the world outside this container
EXPOSE 80

# Define environment variable
ENV NAME World

# Run app.py when the container launches
CMD ["python", "app.py"]

当我运行它时，pip无法安装pika：

 sudo docker build -t sender .
Sending build context to Docker daemon  4.096kB
Step 1/7 : FROM python:3
 ---> 336d482502ab
Step 2/7 : WORKDIR /app
 ---> Using cache
 ---> 9b0ffaad3d8c
Step 3/7 : ADD . /app
 ---> Using cache
 ---> 42aa7eb4ab74
Step 4/7 : RUN pip install --trusted-host pypi.python.org -r requirements.txt
 ---> Running in 24a3943a217b
Collecting pika==0.11.2 (from -r requirements.txt (line 1))
  Retrying (Retry(total=4, connect=None, read=None, redirect=None)) after connection broken by 'NewConnectionError('<pip._vendor.requests.packages.urllib3.connection.VerifiedHTTPSConnection object at 0x7f9911830668>: Failed to establish a new connection: [Errno -3] Temporary failure in name resolution',)': /simple/pika/

我试图安装numpy而不是pika，它有同样的问题。然后我用Google搜索并了解问题出在防火墙上。

首先我尝试像那样运行（https://github.com/docker/compose/issues/2111）：

 sudo docker build --build-arg HTTP_PROXY=$HTTP_PROXY -t sender .

然后我试图关闭代理：

sudo ufw disable

此外，我试图从Dockerfile中删除requirements.txt并用pip install pika替换它。

没有任何帮助。

Answer 1

解决此问题的直接方法是使用主机网络模式进行构建。这将使容器在构建时使用主机newtorking堆栈：

docker build --network=host ...

Answer 2

您确定docker正在使用正确的DNS服务器吗？尝试使用以下参数运行docker：--dns 8.8.8.8。

对于docker build，使用以下内容将文件resolv.conf添加到Dockerfile的目录中

nameserver 8.8.8.8
nameserver 8.8.4.4

然后将Dockerfile更改为

# Use an official Python runtime as a parent image
FROM python:3

# Set the working directory to /app
WORKDIR /app

# Copy resolv.conf
ADD resolv.conf /etc/resolv.conf

# Copy the current directory contents into the container at /app
ADD . /app

# Install any needed packages specified in requirements.txt
RUN pip install --trusted-host pypi.python.org -r requirements.txt

# Make port 80 available to the world outside this container
EXPOSE 80

# Define environment variable
ENV NAME World

# Run app.py when the container launches
CMD ["python", "app.py"]

在Docker中安装Python库

2 个答案: