Conda将一个环境导入到另一个环境

Question

Consider the situation where you're importing a Python submodule with dependencies into a project with its own dependencies. Say that the submodule has its environment.yml file and the project itself has an environment.yml file.

Is there a way to create an environment incorporating both of these environment specifications, and if so, how would you go about doing this? (Or is there a better/more preferred way to handle this situation?)

Answer 1

I'm guessing you're the one developing both the submodule and the project since the dependencies are still in the environment.yml files.

Option 1: Update Project Environment using Submodule's environment.yml

This unfortunately might be your only option if your submodule has dependencies on conda packages.

# First create the project environment
$ conda env create --force -f project_environment.yml

# Then update with submodule dependencies
$ conda env update -n project-env-name --file submodule_environment.yml

This is less than ideal since the basic expectation is that your imported libraries come with their own dependencies.

Option 2: Put dependencies into respective requirements.txt files

This is applicable only if the submodule dependencies can be installed from PyPi via pip . First put the dependencies of the project and submodule into their respective requirements.txt files.

Then restructure the environment.yml files to look the following:

submodule_environment.yml

name: submodule-env-name
channels:
  - defaults
dependencies:
- python=3.6.3             # no conda dependencies
- pip:
    - -r requirements.txt  # <--- submodule dependencies

project_environment.yml

name: project-env-name
channels:
  - defaults
dependencies:
- python=3.6.3
- pip:
    - -r requirements.txt                    # <--- project dependencies
    - -r project/submodule/requirements.txt  # <--- submodule dependencies

In this way you can ignore the submodule_environment.yml file altogether and then create the project environment with a single command.

$ conda env create --force -f project_environment.yml

This approach will not work if your submodule has dependencies on conda packages. If it does then Option 1 is your best option.

Option 3: Package the Submodule (Ideal)

Assuming the submodule has no conda dependencies then it would be ideal to just make a separate package out of the submodule. Create a setup.py and put all the dependencies into the install_requires field. Here's a template of how the setup.py file should look like.

Once it's packaged, you can do the following:

• Install it locally using:
  • pip install .
• Upload to github or bitbucket and install it using:
  • pip install git+https://github.com/username/submodule.git --upgrade
• Upload to github or bitbucket and add the following to requirements.txt or environment.yml under pip :
  • git+https://github.com/username/submodule.git#egg=submodule