Way to specify --no-deps option in requirements.txt?

What’s the problem this feature will solve? I was trying to dockerize my python application that uses aioredis package. I specified the requirement in requirements.txt as:

...
aioredis==1.3.0

And my Dockerfile looks like:

FROM python:3.8-alpine
WORKDIR /app
COPY requirements.txt .
RUN pip install -r requirements.txt
COPY . .
CMD ["python", "main.py"]

But then I get this error when building the image:

...
    Running setup.py install for hiredis: started
    Running setup.py install for hiredis: finished with status 'error'
    ERROR: Command errored out with exit status 1:
     command: /usr/local/bin/python -u -c 'import sys, setuptools, tokenize; sys.argv[0] = '"'"'/tmp/pip-install-yr8xwxtb/hiredis/setup.py'"'"'; __file__='"'"'/tmp/pip-install-yr8xwxtb/hiredis/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' install --record /tmp/pip-record-zhb51yho/install-record.txt --single-version-externally-managed --compile
         cwd: /tmp/pip-install-yr8xwxtb/hiredis/
    Complete output (17 lines):
    running install
    running build
    running build_py
    creating build
    creating build/lib.linux-x86_64-3.8
    creating build/lib.linux-x86_64-3.8/hiredis
    copying hiredis/__init__.py -> build/lib.linux-x86_64-3.8/hiredis
    copying hiredis/version.py -> build/lib.linux-x86_64-3.8/hiredis
    running build_ext
    building 'hiredis.hiredis' extension
    creating build/temp.linux-x86_64-3.8
    creating build/temp.linux-x86_64-3.8/src
    creating build/temp.linux-x86_64-3.8/vendor
    creating build/temp.linux-x86_64-3.8/vendor/hiredis
    gcc -Wno-unused-result -Wsign-compare -DNDEBUG -g -fwrapv -O3 -Wall -DTHREAD_STACK_SIZE=0x100000 -fPIC -Ivendor -I/usr/local/include/python3.8 -c src/hiredis.c -o build/temp.linux-x86_64-3.8/src/hiredis.o
    unable to execute 'gcc': No such file or directory
    error: command 'gcc' failed with exit status 1
    ----------------------------------------
ERROR: Command errored out with exit status 1: /usr/local/bin/python -u -c 'import sys, setuptools, tokenize; sys.argv[0] = '"'"'/tmp/pip-install-yr8xwxtb/hiredis/setup.py'"'"'; __file__='"'"'/tmp/pip-install-yr8xwxtb/hiredis/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' install --record /tmp/pip-record-zhb51yho/install-record.txt --single-version-externally-managed --compile Check the logs for full command output.

So I think this is because inside the alpine based container, there is no gcc available and thus what I can do is to install gcc manually inside the container(using RUN) or install aioredis without hiredis dependency(using --no-deps pip option). I’d prefer latter one, but it seems impossible to achieve with current version of pip when using requirements.txt.

Describe the solution you’d like Add an option to specify --no-deps per requirement.

Alternative Solutions As I said above, there are two alternative solutions for now.

1. Install gcc inside the container:

   FROM python:3.8-alpine
   RUN apk update && apk add build-base  # added this line
   WORKDIR /app
   COPY requirements.txt .
   RUN pip install -r requirements.txt
   COPY . .
   CMD ["python", "main.py"]
   

   It works well, but I don’t want to install whole build-base packages just to install a single package in python.

2. Use --no-deps option in Dockerfile:

   FROM python:3.8-alpine
   WORKDIR /app
   COPY requirements.txt .
   RUN pip install -r requirements.txt  --no-deps  # added --no-deps option here
   COPY . .
   CMD ["python", "main.py"]
   

   But in this approach I have to specify full requirements list using pip freeze or something, rather than specifying package names by hand.

Additional context

[chrahunt]

Thank you for your understanding. Please don’t hesitate to share any other thoughts or issues. 😃

[hallazzang]

@chrahunt Thank you for response, I got your point and that suggestion would definitely work. I’ll close this issue.