Medium multiply

A small demo library for a Medium publication about publishing libraries.

Installation

pip install projectname

if we upload the package to PyPI. Otherwise, we can install it from a local directory:

pip install -e .

The flag -e stands for editable, which means that if we make changes to the code, we don’t need to reinstall the package. This is for the dev process. For prod, we can just install the package without the -e flag.

Essence

The current Python logic is still valid. To create a Python library, we need to be aware of some additional knowledge.

1. Create an empty file called setup.py. This is one of the most important files when creating a Python library! Additionally, we need pyproject.toml file to specify how we build the library. And we use the build library and python -m build to build the library.
2. Create an empty file called README.md. This is the place where you can write markdown to describe the contents of your library for other users.
3. Create a folder called mypythonlib, or whatever you want your Python library to be called when you pip install it. (The name should be unique on pip if you want to publish it later.) How to check the uniqueness? Just search for the name on pip. If it’s not there, you’re good to go.
4. Create an empty file inside mypythonlib that is called __init__.py. Basically, any folder that has an __init__.py file in it, will be included in the library when we build it. Most of the time, you can leave the __init__.py files empty. Upon import, the code within __init__.py gets executed, so it should contain only the minimal amount of code that is needed to be able to run your project. For now, we will leave them as is.
5. Create functional code in the folder where __init__.py is located.
6. Finally, create a folder tests in your root folder. Inside, create an empty init.py file. Add some empty file as you want. If we wish to compile the code into a library, we have to make sure the code is robust. And the test is necessary. If you want to use the test, just install pytest and pytest-runner. Then, run python setup.py pytest to run the all the tests in the tests folder.

After build, I have a dist folder, and we have a package with .whl and .tar.gz files. We can install the package with pip install mypythonlib-0.0.1-py3-none-any.whl or pip install mypythonlib-0.0.1.tar.gz.