How to use virtualenv in makefile

Question

I want to perform several operations while working on a specified virtualenv.

For example command

make install

would be equivalent

Answer 1

You should use this, it's functional for me at moment.

report.ipynb : merged.ipynb
    ( bash -c "source ${HOME}/anaconda3/bin/activate py27; which -a python; \
        jupyter nbconvert \
        --to notebook \
        --ExecutePreprocessor.kernel_name=python2 \
        --ExecutePreprocessor.timeout=3000 \
        --execute merged.ipynb \
        --output=$< $<" )

Answer 2

I have had luck with this.

install:
    source ./path/to/bin/activate; \
    pip install -r requirements.txt; \

Answer 3

In make you can run a shell as command. In this shell you can do everything you can do in a shell you started from comandline. Example:

install:
    ( \
       source path/to/virtualenv/bin/activate; \
       pip install -r requirements.txt; \
    )

Attention must be paid to the ;and the \.

Everything between the open and close brace will be done in a single instance of a shell.

Answer 4

Normally make runs every command in a recipe in a different subshell. However, setting .ONESHELL: will run all the commands in a recipe in the same subshell, allowing you to activate a virtualenv and then run commands inside it.

Note that .ONESHELL: applies to the whole Makefile, not just a single recipe. It may change behaviour of existing commands, details of possible errors in the full documentation. This will not let you activate a virtualenv for use outside the Makefile, since the commands are still run inside a subshell.

Reference documentation: https://www.gnu.org/software/make/manual/html_node/One-Shell.html

Example:

.ONESHELL:

.PHONY: install
install:
    source path/to/virtualenv/bin/activate
    pip install -r requirements.txt

Answer 5

Based on the answers above (thanks @Saurabh and @oneself!) I've written a reusable Makefile that takes care of creating virtual environment and keeping it updated: https://github.com/sio/Makefile.venv

It works by referencing correct executables within virtualenv and does not rely on the "activate" shell script. Here is an example:

test: venv
    $(VENV)/python -m unittest

include Makefile.venv

Differences between Windows and other operating systems are taken into account, Makefile.venv should work fine on any OS that provides Python and make.

Answer 6

I like using something that runs only when requirements.txt changes:

This assumes that source files are under project in your project's root directory and that tests are under project/test. (You should change project to match your actually project name.)

venv: venv/touchfile

venv/touchfile: requirements.txt
    test -d venv || virtualenv venv
    . venv/bin/activate; pip install -Ur requirements.txt
    touch venv/touchfile

test: venv
    . venv/bin/activate; nosetests project/test

clean:
    rm -rf venv
    find -iname "*.pyc" -delete

• Run make to install packages in requirements.txt.
• Run make test to run your tests (you can update this command if your tests are somewhere else).
• run make clean to delete all artifacts.