SeleniumBase/examples/presenter/py_virtual_envs.py

195 lines
8.0 KiB
Python

from seleniumbase import BaseCase
BaseCase.main(__name__, __file__)
class PythonVirtualEnvs(BaseCase):
def test_py_virtual_envs(self):
self.create_presentation(theme="serif", transition="slide")
self.add_slide(
"<h2>Python Virtual Environments:</h2><br />\n"
"<h2>What, Why, and How</h2><hr /><br />\n"
"<h3>Presented by <b>Michael Mintz</b></h3>\n"
"<p>Granite State Code Camp - Sat, Nov 14, 2020</p>"
)
self.add_slide(
"<p><b>About me:</b></p>\n"
"<ul>"
"<li>I created the <b>SeleniumBase</b> framework.</li>"
"<li>I'm currently the DevOps Lead at <b>iboss</b>.</li>"
"</ul>\n",
image="https://seleniumbase.io/other/iboss_booth.png",
)
self.add_slide(
"<p><b>Topics & tools covered by this presentation:</b></p>"
"<hr /><br />\n"
"<ul>"
"<li>Overview of Virtual Environments</li>"
"<li>Python package management</li>"
'<li>Python 3 "venv"</li>'
"<li>virtualenv / virtualenvwrapper</li>"
'<li>pip / "pip install"</li>'
"<li>requirements.txt files</li>"
"<li>setup.py files</li>"
"</ul>"
)
self.add_slide(
"<p><b>Topics & tools that are NOT covered here:</b></p><hr />\n"
"<br /><div><ul>"
'<li>"conda"</li>'
'<li>"pipenv"</li>'
'<li>"poetry"</li>'
'<li>"pipx"</li>'
"</ul></div><br />"
"<p>(Other Python package management tools)</p>"
)
self.add_slide(
"<p><b>What is a Python virtual environment?</b></p><hr /><br />\n"
"<p>A Python virtual environment is a partitioned directory"
" where a Python interpreter, libraries/packages, and scripts"
" can be installed and isolated from those installed in other"
" virtual environments or the global environment.</p>"
)
self.add_slide(
"<p><b>Why should we use Python virtual environments?</b>"
"</p><hr /><br />\n"
"<p>We should use Python virtual environments because different"
" Python projects can have conflicting Python dependencies that"
" cannot coexist in the same env.</p>"
)
self.add_slide(
"<p><b>Why? - continued</b></p><hr /><br />\n"
"<p>Example: Project A and Project B both depend on"
" different versions of the same Python library!</p>"
"<p>Therefore, installing the second project requirements"
" would overwrite the first one, causing it to break.</p>",
code=(
"# Project A requirement:\n"
"urllib3==1.25.3\n\n"
"# Project B requirement:\n"
"urllib3==1.26.2"
),
)
self.add_slide(
"<p><b>Why? - continued</b></p><hr /><br />\n"
"<p>It is also possible that Project A and Project B"
" require different versions of Python installed!</p>",
code=(
"# Project A requirement:\n"
"Python-3.8\n\n"
"# Project B requirement:\n"
"Python-2.7"
),
)
self.add_slide(
"<p><b>How do we create and use Python virtual envs?</b>"
"</p><hr /><br />\n"
"<div><b>There are tools/scripts we can use:</b></div><br />"
"<ul>"
'<li>The Python 3 "venv" command</li>'
"<li>virtualenv / virtualenvwrapper</li>"
"</ul>"
)
self.add_slide(
'<p><b>Python 3 "venv"</b></p><hr /><br />\n'
'"venv" creates virtual environments in the location where run'
" (generally with Python projects).",
code=(
"# Mac / Linux\n"
"python3 -m venv ENV_NAME\n"
"source ENV_NAME/bin/activate\n\n"
"# Windows\n"
"py -m venv ENV_NAME\n"
"call ENV_NAME\\Scripts\\activate\n\n"
'# (Type "deactivate" to leave a virtual environment.)'
),
)
self.add_slide(
'<p><b>"mkvirtualenv" (from virtualenvwrapper)</b></p><hr />\n'
'<br />"mkvirtualenv" creates virtual environments in one place'
" (generally in your home directory).",
code=(
"# Mac / Linux\n"
"python3 -m pip install virtualenvwrapper\n"
"export WORKON_HOME=$HOME/.virtualenvs\n"
"source `which virtualenvwrapper.sh`\n"
"mkvirtualenv ENV_NAME\n\n"
"# Windows\n"
"py -m pip install virtualenvwrapper-win\n"
"mkvirtualenv ENV_NAME\n\n"
'# (Type "deactivate" to leave a virtual environment.)'
),
)
self.add_slide(
"<p><b>List of commands from virtualenvwrapper</b></p>"
"<hr /><br />",
code=(
"# Create a virtual environment:\n"
"mkvirtualenv ENV_NAME\n\n"
"# Exit your virtual environment:\n"
"deactivate\n\n"
"# Re-enter a virtual environment:\n"
"workon ENV_NAME\n\n"
"# List all virtual environments:\n"
"workon\n\n"
"# Delete a virtual environment:\n"
"rmvirtualenv ENV_NAME"
),
)
self.add_slide(
"<p><b>Determining if you are in a virtual env</b></p>"
"<hr /><br />"
"<p>When activated, the name of your virtual env"
" will appear in parentheses on the left side of your"
" command prompt.</p>",
code=(
"# Example of how it may look on a Windows machine:\n"
"C:\\Users\\Michael\\github> mkvirtualenv my_env\n"
"(my_env) C:\\Users\\Michael\\github>"
),
)
self.add_slide(
'<p><b>Installing packages with "pip install"</b></p><hr /><br />'
"<p>Once you have created a Python virtual environment and are"
" inside, it is now safe to install packages from PyPI,"
" setup.py files, and/or requirements.txt files.</p>\n",
code=(
"# Install a package from PyPI:\n"
"pip install seleniumbase\n\n"
"# Install packages from a folder with setup.py:\n"
"pip install . # Normal installation\n"
"pip install -e . # Editable install\n\n"
"# Install packages from a requirements.txt file:\n"
"pip install -r requirements.txt\n"
),
)
self.add_slide(
'<p><b>Other useful "pip" commands</b></p><hr /><br />',
code=(
"# See which Python packages are installed:\n"
"pip list\n\n"
"# See which installed Python packages are outdated:\n"
"pip list --outdated\n\n"
"# Create a requirements file from installed packages:\n"
"pip freeze > my_requirements.txt"
),
)
self.add_slide(
"<br /><br /><h2><b>Live Demo Time!</b></h2><hr /><br />",
image="https://seleniumbase.io/other/python_3d_logo.png",
)
self.add_slide(
"<h2><b>The End. Questions?</b></h2><hr /><br />\n"
"<h3>Where to find me:</h3>"
"<ul>"
'<li><a href="https://github.com/mdmintz">'
"github.com/mdmintz</a></li>"
'<li><a href="https://github.com/seleniumbase/SeleniumBase">'
"github.com/seleniumbase/SeleniumBase</a></li>"
'<li><a href="https://seleniumbase.io/">'
"seleniumbase.io</a></li>"
"</ul>"
)
self.begin_presentation(
filename="py_virtual_envs.html", show_notes=False, interval=0
)