Change pip Registry in Dockerfile

Default pip resigtry is desperately slow in China. That makes building python docker image a PITA. Luckily we can config Dockerfile with a different pip registry:

# Dockerfile
# Set environment variables
ENV PYTHONDONTWRITEBYTECODE 1
ENV PYTHONUNBUFFERED 1
...
# Upgrade pip then change pip registry
RUN pip install -i https://pypi.tuna.tsinghua.edu.cn/simple pip -U
RUN pip config set global.index-url https://pypi.tuna.tsinghua.edu.cn/simple
...
RUN pip install --no-cache-dir -r requirements.txt

--no-cache-dir will shrink the image size by disabling the cache. It's a good practice to use it for building docker images.



If changing ubuntu source is needed:

# Dockerfile
RUN sed -i s/archive.ubuntu.com/mirrors.aliyun.com/g /etc/apt/sources.list
&& sed -i s/security.ubuntu.com/mirrors.aliyun.com/g /etc/apt/sources.list
&& apt-get update && apt-get upgrade