Python Table Manners- Cut the Cookie Gracefully @ Euro Python 2020

### Goals
I expect the audiences to gain knowledge of the tools I mention and the primary usage of them. The tools will cover various aspects of software engineering (e.g., dependencies, testing, security, etc.). Also, I'll purpose how I combine all these tools in my development workflow as a sample for how the audiences can integrate these tools into their workflow.

### Outline for 30 minutes
* Dependency Management (4 min)
* Testing - Don't let your customer debug for you (4 min)
* Style Check and auto-fix (4 min)
* Task Management - No more repetitive typing (3 min)
* pre-commit - Prevent committing bad code into codebase (3 min)
* commitizen-tool - How good commit message can help (4 min)
* Security (3 min)
* Cookiecutter - Wrap up all the tools (3 min)
* Q & A (2 min)

### Outline for 45 minutes
* Dependency Management (5 min)
* Testing - Don't let your customer debug for you (5 min)
* Style Check and auto-fix (5 min)
* Task Management - No more repetitive typing (5 min)
* pre-commit - Prevent committing bad code into codebase (5 min)
* commitizen-tool - How good commit message can help (5 min)
* Security (5 min)
* Continuous Integration - Assemble all the trivial steps (5 min)
* Cookiecutter - Wrap up all the tools (3 min)
* Q & A (2 min)

Transcript

1. @clleew
   Python Table Manners:
   Cut the Cookie Gracefully
   
   A Guideline Toward Cleaner Code
   

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2. @clleew
   $ cat speaker.py
   __name__ = "Wei Lee / 李唯"
   __position__ = [
   "Software Engineer @ Rakuten Slice",
   "Volunteer @ PyCon Taiwan",
   "Maintainer of commitizen-tools",
   ]
   __twitter__ = " @clleew"
   __github__ = " Lee-W"
   __blog__ = " http://lee-w.github.io"
   

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3. @clleew
   Outline
   • Clean up the table - Dependency Management
   • Put the correct tablewares - Testing
   • Use the tablewares elegantly - Coding Style
   • Mnemonic phrase - Task management
   • Say please! - Check before git operation
   • Speak formally - Cultivate a git commit convention
   • Safety matters - Security Issues
   • Where's the Cookie? - Project template
   

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4. @clleew
   Dependency Management
   Clean up the table
   

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5. @clleew
   How we used to start
   a Python project
   

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6. @clleew
   Sometimes we just forgot to…
   • ... activate / deactivate virtual environment
   • ... add package into requirements.txt
   

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7. @clleew
   Pipenv
   Python Dev Workflow for Humans
   • manage virtual environment + package
   → update at once
   → No more manual sync up!
   • generate hashes from packages
   → ensure getting the same packages next time
   

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8. @clleew
   Initial Virtual Environment
   

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9. @clleew
   Empty Pipfile
   [[source]]
   name = "pypi"
   url = "https://pypi.org/simple"
   verify_ssl = true
   [dev-packages]
   [packages]
   [requires]
   python_version = "3.7"
   

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10. @clleew
    Install Package
    

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11. @clleew
    Pipfile with “requests”
    [[source]]
    name = "pypi"
    url = "https://pypi.org/simple"
    verify_ssl = true
    [dev-packages]
    [packages]
    requests = "*"
    [requires]
    python_version = "3.7"
    [packages]
    requests = "*"
    

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12. @clleew
    "requests": {
    "hashes": [
    "sha256:11e007a8a2aa0323f5a921e9e6a2d7e4e67d9877e85773fba9ba6419025cbeb4",
    "sha256:9cf5292fcd0f598c671cfc1e0d7d1a7f13bb8085e9a590f48c010551dc6c4b31"
    ],
    "index": "pypi",
    "version": "==2.22.0"
    },
    {
    ......
    "default": {
    ......
    "requests": {
    "hashes": [
    "sha256:11e007a8a2aa0323f5a921e9e6a2d7e4e67d9877e85773fba9ba6419025cbeb4",
    "sha256:9cf5292fcd0f598c671cfc1e0d7d1a7f13bb8085e9a590f48c010551dc6c4b31"
    ],
    "index": "pypi",
    "version": "==2.22.0"
    },
    "urllib3": {
    "hashes": [
    "sha256:3de946ffbed6e6746608990594d08faac602528ac7015ac28d33cee6a45b7398",
    "sha256:9a107b99a5393caf59c7aa3c1249c16e6879447533d0887f4336dde834c7be86"
    ],
    "version": "==1.25.6"
    }
    },
    ......
    }
    Pipfile.lock with “requests”
    

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13. @clleew
    "requests": {
    "hashes": [
    "sha256:11e007a8a2aa0323f5a921e9e6a2d7e4e67d9877e85773fba9ba6419025cbeb4",
    "sha256:9cf5292fcd0f598c671cfc1e0d7d1a7f13bb8085e9a590f48c010551dc6c4b31"
    ],
    "index": "pypi",
    "version": "==2.22.0"
    },
    {
    ......
    "default": {
    ......
    "requests": {
    "hashes": [
    "sha256:11e007a8a2aa0323f5a921e9e6a2d7e4e67d9877e85773fba9ba6419025cbeb4",
    "sha256:9cf5292fcd0f598c671cfc1e0d7d1a7f13bb8085e9a590f48c010551dc6c4b31"
    ],
    "index": "pypi",
    "version": "==2.22.0"
    },
    "urllib3": {
    "hashes": [
    "sha256:3de946ffbed6e6746608990594d08faac602528ac7015ac28d33cee6a45b7398",
    "sha256:9a107b99a5393caf59c7aa3c1249c16e6879447533d0887f4336dde834c7be86"
    ],
    "version": "==1.25.6"
    }
    },
    ......
    }
    Pipfile.lock with “requests”
    You’re guaranteed to install the
    exact same package next time.
    

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14. @clleew
    

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15. @clleew
    Install package only in dev
    

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16. @clleew
    Pipfile with “pytest"
    [[source]]
    name = "pypi"
    url = "https://pypi.org/simple"
    verify_ssl = true
    [dev-packages]
    pytest = "*"
    [packages]
    requests = "*"
    [requires]
    python_version = "3.7"
    [dev-packages]
    pytest = "*"
    

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17. @clleew
    Run in virtual environment
    

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18. @clleew
    Some people might say
    that pipenv ...
    • ... does not update frequently.
    
    • ... locks slowly.
    
    • ... does not syncs up with install_requires in setup.py
    

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19. @clleew
    Poetry
    

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20. @clleew
    Poetry commands
    

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21. @clleew
    Testing
    Put the correct tablewares
    

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22. @clleew
    unittest
    Unit testing framework in Python Standard Library
    

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23. @clleew
    pytest
    

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24. @clleew
    Why pytest
    • More Pythonic
    
    • Compatible with old unittest tests
    
    • No more assert.+ (e.g., assertEqual, assertTrue, etc.)

    → just assert
    
    • Better test discovery
    
    • Advance features: mark, parameterize, etc.
    
    • Plenty of plugins
    

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25. @clleew
    Run pytest
    

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26. @clleew
    Run pytest
    

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27. @clleew
    always run python inside a virtual environment
    

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28. @clleew
    unittest style tests
    import unittest
    from atta.partner import sponsor
    class TestSponsor(unittest.TestCase):
    def setUp(self):
    sponsors = sponsor.get_all_sponsors('./data/packages.yaml',
    './data/sponsors.yaml')
    self.sponsors = sponsors
    ......
    def test_sponsor_number(self):
    self.assertEqual(len(self.sponsors), 1)
    .......
    

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29. @clleew
    unittest style tests
    import unittest
    from atta.partner import sponsor
    class TestSponsor(unittest.TestCase):
    def setUp(self):
    sponsors = sponsor.get_all_sponsors('./data/packages.yaml',
    './data/sponsors.yaml')
    self.sponsors = sponsors
    ......
    def test_sponsor_number(self):
    self.assertEqual(len(self.sponsors), 1)
    .......
    Prepare all the data needed in test cases
    

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30. @clleew
    unittest style tests
    import unittest
    from atta.partner import sponsor
    class TestSponsor(unittest.TestCase):
    def setUp(self):
    sponsors = sponsor.get_all_sponsors('./data/packages.yaml',
    './data/sponsors.yaml')
    self.sponsors = sponsors
    ......
    def test_sponsor_number(self):
    self.assertEqual(len(self.sponsors), 1)
    .......
    

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31. @clleew
    unittest style tests
    import unittest
    from atta.partner import sponsor
    class TestSponsor(unittest.TestCase):
    def setUp(self):
    sponsors = sponsor.get_all_sponsors('./data/packages.yaml',
    './data/sponsors.yaml')
    self.sponsors = sponsors
    ......
    def test_sponsor_number(self):
    self.assertEqual(len(self.sponsors), 1)
    .......
    

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32. @clleew
    pytest style tests
    import pytest
    from report_generator.partner import sponsor
    class TestSponsor:
    @pytest.fixture(scope="class")
    def sponsors(self):
    return sponsor.get_all_sponsors("test/data/packages.yaml",
    “test/data/sponsors.yaml")
    ......
    def test_sponsor_number(self, sponsors):
    assert len(sponsors) == 1
    ......
    

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33. @clleew
    pytest style tests
    import pytest
    from report_generator.partner import sponsor
    class TestSponsor:
    @pytest.fixture(scope="class")
    def sponsors(self):
    return sponsor.get_all_sponsors("test/data/packages.yaml",
    “test/data/sponsors.yaml")
    ......
    def test_sponsor_number(self, sponsors):
    assert len(sponsors) == 1
    ......
    Prepare the data needed in separate fixtures
    

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34. @clleew
    pytest style tests
    import pytest
    from report_generator.partner import sponsor
    class TestSponsor:
    @pytest.fixture(scope="class")
    def sponsors(self):
    return sponsor.get_all_sponsors("test/data/packages.yaml",
    “test/data/sponsors.yaml")
    ......
    def test_sponsor_number(self, sponsors):
    assert len(sponsors) == 1
    ......
    

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35. @clleew
    pytest style tests
    import pytest
    from report_generator.partner import sponsor
    @pytest.fixture(scope="function")
    def sponsors():
    return sponsor.get_all_sponsors("test/data/packages.yaml",
    "test/data/sponsors.yaml")
    def test_sponsor_number(sponsors):
    assert len(sponsors) == 1
    

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36. @clleew
    pytest style tests
    import pytest
    from report_generator.partner import sponsor
    @pytest.fixture(scope="function")
    def sponsors():
    return sponsor.get_all_sponsors("test/data/packages.yaml",
    "test/data/sponsors.yaml")
    def test_sponsor_number(sponsors):
    assert len(sponsors) == 1
    

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37. @clleew
    Configuration - pytest.ini
    [pytest]
    addopts = --strict-markers
    norecursedirs = .* build dist CVS _darcs {arch} *.egg venv env
    virtualenv
    Configure through pyproject.toml will be when 6.0 released #7247
    

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38. @clleew
    Pytest - powerful plugins
    • pytest-mock: Replace objects that are hard to test with
    fake objects
    
    • pytest-cov: Generate test coverage report
    
    • pytest-xdist: Distributed testing
    
    • and etc.
    

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39. @clleew
    Coding Style
    Use the tablewares elegantly
    

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40. @clleew
    flake8
    • Enforcing style consistency across Python project
    
    • Check possible errors before running your program
    
    • Eliminate bad style
    

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41. @clleew
    import os
    os = "My Operating system"
    Example - bad_code.py
    

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42. @clleew
    import os
    os = "My Operating system"
    redefinition of imported library

    (possible error)
    Example - bad_code.py
    

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43. @clleew
    import os
    os = "My Operating system"
    additional space

    (bad coding style)
    redefinition of imported library

    (possible error)
    Example - bad_code.py
    

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44. @clleew
    Run flake8
    

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45. @clleew
    Configuration - setup.cfg
    [flake8]
    ignore =
    # F632: use ==/!= to compare str, bytes, and int literals
    F632,
    # W503: Line break occurred before a binary operator
    W503,
    # E501: Line too long
    E501,
    # E203: Whitespace before ':' (for black)
    E203
    exclude =
    .git,
    __pycache__,
    build,
    dist
    max-line-length = 88
    

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46. @clleew
    Pylint
    

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47. @clleew
    import os
    os = "My Operating system"
    additional space

    (bad coding style)
    redefinition of imported library

    (possible error)
    Example - bad_code.py
    

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48. @clleew
    Run pylint
    

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49. @clleew
    Run pylint with "-r" argument
    A bunch of reports that 

    you can compare 

    with your previous run
    

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50. Configuration - pyproject.toml
    [tool.pylint.messages_control]
    disable = [
    "bad-continuation",
    "missing-function-docstring",
    "missing-module-docstring",
    "invalid-name"
    ]
    [tool.pylint.format]
    max-line-length = 88
    

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51. @clleew
    mypy
    • Static type checker
    
    • Compile-time type checking

    → avoid possible runtime errors
    
    • Type annotation enhances readability

    → machine-checked documentation
    

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52. from typing import List
    def func(vals: List[str]):
    for val in vals:
    assert isinstance(val, str)
    func([1, 2, 3])
    Example - error_type.py
    List[str]
    [1, 2, 3]
    

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53. from typing import List
    def func(vals: List[str]):
    for val in vals:
    assert isinstance(val, str)
    func([1, 2, 3])
    Example - error_type.py
    List[str]
    [1, 2, 3]
    

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54. Run mypy
    

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55. Run mypy
    all the files with .py extension
    

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56. Run mypy
    ignore errors that libs that is not type annotated
    

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57. @clleew
    Configuration - setup.cfg
    [mypy]
    files = **/*.py
    ignore_missing_imports = true
    follow_imports = silent
    warn_redundant_casts = True
    warn_unused_ignores = True
    warn_unused_configs = True
    [mypy]
    files = **/*.py
    ignore_missing_imports = true
    

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58. @clleew
    Configuration - setup.cfg
    [mypy]
    files = **/*.py
    ignore_missing_imports = true
    follow_imports = silent
    warn_redundant_casts = True
    warn_unused_ignores = True
    warn_unused_configs = True
    [mypy]
    files = **/*.py
    ignore_missing_imports = true
    

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59. Run mypy with configuration
    

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60. @clleew
    One step forward
    Fix the style automatically
    

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61. Black
    

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62. Run Black
    

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63. How Black reformat
    

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64. How Black reformat
    

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65. Why Black?
    The black code style is not configurable.
    

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66. Why Black?
    The black code style is not configurable.
    No more arguing about which style is better
    

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67. –The Zen of Python, by Tim Peters
    “There should be one-- and preferably only
    one --obvious way to do it.”
    

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68. @clleew
    Configuration - pyproject.toml
    [tool.black]
    line-length = 88
    include = '\.pyi?$'
    exclude = '''
    /(
    \.eggs
    | \.git
    | \.hg
    | \.mypy_cache
    | \.tox
    | \.venv
    | _build
    | buck-out
    | build
    | dist
    )/
    '''
    

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69. Isort
    

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70. Example
    wrong_import_order.py
    import django
    import os
    import some_custom_package
    import flask
    import datetime
    ...
    

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71. According to PEP8
    • Imports should be grouped in the following order:
    1. Standard library imports.
    2. Related third party imports.
    3. Local application/library specific imports.
    • You should put a blank line between each group
    of imports.
    

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72. Run Isort
    

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73. Run Isort
    import datetime
    import os
    import django
    import flask
    import some_custom_package
    ...
    

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74. @clleew
    Configuration - pyproject.toml
    [tool.isort]
    line_length = 88
    multi_line_output = 3
    include_trailing_comma = true
    force_grid_wrap = 0
    use_parentheses = true
    

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75. Style formatting and linting
    

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77. @clleew
    Task Management
    Mnemonic phrase
    

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78. Invoke
    • Task execution tool that can manage your
    commands
    • It’s like a Makefile but in Python.
    

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79. Invoke in practice (rg-cli)
    

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80. Before invoke in rg-cli
    

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81. Before invoke in rg-cli
    

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82. After invoke in rg-cli
    

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83. List all commands
    

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84. How ? - tasks.py
    from invoke import task
    VENV_PREFIX = "pipenv run"
    ......
    @task
    def install(cmd):
    """Install script in pipenv environment"""
    cmd.run(f"{VENV_PREFIX} python setup.py install")
    

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85. How ? - tasks.py
    from invoke import task
    VENV_PREFIX = "pipenv run"
    ......
    @task
    def install(cmd):
    """Install script in pipenv environment"""
    cmd.run(f"{VENV_PREFIX} python setup.py install")
    

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86. How ? - tasks.py
    from invoke import task
    VENV_PREFIX = "pipenv run"
    ......
    @task
    def install(cmd):
    """Install script in pipenv environment"""
    cmd.run(f"{VENV_PREFIX} python setup.py install")
    

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87. Modulize - Namespace
    

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88. Autocomplete
    

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89. Autocomplete
    

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90. Autocomplete
    

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91. Why not use Makefile?
    1.We’re Python developers!
    2.Some tasks might not be easy to handle through
    shell script.
    3.Combining Python and shell script
    

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92. @clleew
    Check before git operation
    Say please!
    

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93. @clleew
    pre-commit
    • Why?
    
    • Sometimes we still forget to run the check commands.
    
    • Prevent committing bad code into codebase
    
    • How?
    
    • pre-commit runs these commands before we do git
    operations (e.g., git push, git commit)
    

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94. @clleew
    Config (customized hooks)
    .pre-commit-config.yaml
    repos:
    - repo: local
    hooks:
    - id: style-reformat
    name: style-reformat
    stages: [commit]
    language: system
    pass_filenames: false
    entry: inv style.reformat
    types: [python]
    - id: style-check
    name: style-check
    stages: [push]
    language: system
    pass_filenames: false
    entry: inv style
    types: [python]
    ......
    

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95. @clleew
    Config (customized hooks)
    .pre-commit-config.yaml
    repos:
    - repo: local
    hooks:
    - id: style-reformat
    name: style-reformat
    stages: [commit]
    language: system
    pass_filenames: false
    entry: inv style.reformat
    types: [python]
    - id: style-check
    name: style-check
    stages: [push]
    language: system
    pass_filenames: false
    entry: inv style
    types: [python]
    ......
    entry: inv style.reformat
    - id: style-reformat
    stages: [commit]
    

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96. @clleew
    Config (customized hooks)
    .pre-commit-config.yaml
    repos:
    - repo: local
    hooks:
    - id: style-reformat
    name: style-reformat
    stages: [commit]
    language: system
    pass_filenames: false
    entry: inv style.reformat
    types: [python]
    - id: style-check
    name: style-check
    stages: [push]
    language: system
    pass_filenames: false
    entry: inv style
    types: [python]
    ......
    stages: [push]
    - id: style-check
    

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97. @clleew
    Config (existing hooks)
    .pre-commit-config.yaml
    ......
    - repo: https://github.com/pre-commit/pre-commit-hooks
    rev: v3.1.0
    hooks:
    - id: end-of-file-fixer
    - id: trailing-whitespace
    args: [--markdown-linebreak-ext=md]
    

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98. @clleew
    Setup pre-commit
    

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99. @clleew
    Run pre-commit
    

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100. @clleew
     Run pre-commit
     

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101. @clleew
     Cultivate
     a git commit convention
     Speak formally
     

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102. View Slide

103. Hard to find to the right version
     

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104. commitizen-tools
     

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105. Commit - cz commit
     

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106. Commit - cz commit
     

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107. Commit - cz commit
     

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108. Commit - cz commit
     

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109. Commit - cz commit
     

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110. Commit - cz commit
     

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111. Commit - cz commit
     

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112. Standardized git commits
     

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113. Standardized git commits
     

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114. Other Commitizen features
     • pre-commit hook prevents you from not using
     commitizen
     • customizable commit rules
     • auto bump project version (SemVar)
     • auto generate changelog (Keep a Changelog)
     

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115. Let’s Sprint!
     

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116. Let’s Sprint!
     

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117. @clleew
     Security Issues
     Safety matters
     

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120. Safety
     Dependency Checking
     

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121. Check vulnerability
     in current environment
     

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122. Check vulnerability
     in current environment
     

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123. But if you use pipenv …
     

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124. But if you use pipenv …
     

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125. How does Safety work?
     • Search the vulnerability in CVS
     (Common Vulnerabilities and Exposures)
     • Free DB: update monthly
     • Paid DB: update realtime
     

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126. Bandit
     Static Analysis
     

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127. Check Common Security
     Issue in Python Code
     

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128. Check Common Security
     Issue in Python Code
     

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129. Check Common Security
     Issue in Python Code
     

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130. Check Common Security
     Issue in Python Code
     

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131. Check Common Security
     Issue in Python Code
     

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132. Not all the warnings
     should be fixed
     • Add exclude into your bandit configuration
     • Add # nosec after the end of the code to skip
     the warning
     

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133. @clleew
     

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134. @clleew
     Project template
     Where's the Cookie?
     

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135. @clleew
     We want these manners in all our Python projects ❗
     

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136. @clleew
     We want these manners in all our Python projects ❗
     But... we don't want to configure it everytime ❗
     

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137. @clleew
     Create a project template once
     and initialize projects through it
     

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138. @clleew
     Lee-W / cookiecutter-python-template
     

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139. @clleew
     

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140. @clleew
     

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141. @clleew
     

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142. @clleew
     

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143. @clleew
     

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144. @clleew
     How to make a template?
     cookiecutter.json
     

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145. @clleew
     How to make a template?
     cookiecutter.json
     

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146. @clleew
     Template structure
     Cookiecutter configuration
     Template (Use Jinja)
     

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147. @clleew
     An example in template
     {{cookiecutter.project_slug}}/tasks/env.py
     from invoke import task
     from tasks.common import VENV_PREFIX
     @task
     def init(ctx):
     """Install production dependencies"""
     {% if cookiecutter.dependency_management_tool == 'pipenv' -%}
     ctx.run("pipenv install --deploy")
     {%- elif cookiecutter.dependency_management_tool == 'poetry' -%}
     ctx.run("poetry install --no-dev")
     {%- endif %}
     {% if cookiecutter.dependency_management_tool == 'pipenv' -%}
     ctx.run("pipenv install --deploy")
     

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148. @clleew
     An example in template
     {{cookiecutter.project_slug}}/tasks/env.py
     from invoke import task
     from tasks.common import VENV_PREFIX
     @task
     def init(ctx):
     """Install production dependencies"""
     {% if cookiecutter.dependency_management_tool == 'pipenv' -%}
     ctx.run("pipenv install --deploy")
     {%- elif cookiecutter.dependency_management_tool == 'poetry' -%}
     ctx.run("poetry install --no-dev")
     {%- endif %}
     {% if cookiecutter.dependency_management_tool == 'pipenv' -%}
     ctx.run("pipenv install --deploy")
     

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149. @clleew
     An example in template
     {{cookiecutter.project_slug}}/tasks/env.py
     from invoke import task
     from tasks.common import VENV_PREFIX
     @task
     def init(ctx):
     """Install production dependencies"""
     {% if cookiecutter.dependency_management_tool == 'pipenv' -%}
     ctx.run("pipenv install --deploy")
     {%- elif cookiecutter.dependency_management_tool == 'poetry' -%}
     ctx.run("poetry install --no-dev")
     {%- endif %}
     {%- elif cookiecutter.dependency_management_tool == 'poetry' -%}
     ctx.run("poetry install --no-dev")
     {%- endif %}
     

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150. @clleew
     import os
     def remove_pipfile():
     os.remove("Pipfile")
     def main():
     if "{{ cookiecutter.dependency_management_tool }}" != "pipenv":
     remove_pipfile()
     if __name__ == "__main__":
     main()
     Run before/after project is generated
     hooks/post_gen_project.py
     

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151. @clleew
     Lee-W / cookiecutter-python-template
     

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152. @clleew
     

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153. Other Tools
     • Testing
     • Hypothesis
     • nox
     • Documentation
     • Mkdocs
     • Sphinx
     

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154. @clleew
     Related Talks
     • Dependency Management
     • Tzu-ping Chung - 這樣的開發環境沒問題嗎？ (PyCon TW 2018)
     • Kenneth Reitz - Pipenv: The Future of Python Dependency
     Management (PyCon US 2018)
     • Patrick Muehlbauer - Python Dependency Management (PyCon DE
     2018)
     • Test
     • Chun-Yu Tseng - 快快樂樂成為 Coding Ninja (by pytest) (PyCon APAC
     2015)
     • Florian Bruhin – Pytest: Rapid Simple Testing (Swiss Python Summit 16)
     

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155. @clleew
     Related Talks
     • Style Check
     • Kyle Knapp - Automating Code Quality (PyCon US 2018)
     • Łukasz Langa - Life Is Better Painted Black, or: How to Stop Worrying and Embrace Auto-Formatting
     (PyCon US 2019)
     • Raymond Hettinger - Beyond PEP 8 -- Best practices for beautiful intelligible code (PyCon 2015)
     • Static Typing
     • Dustin Ingram - Static Typing in Python (PyCon US 2020)
     • Task Managements
     • Thea Flowers - Break the Cycle: Three excellent Python tools to automate repetitive tasks (PyCon US
     2019)
     • Security
     • Terri Oda - Python Security Tools (PyCon US 2019)
     • Tennessee Leeuwenburg - Watch out for Safety Bandits! (PyCon AU 2018)
     

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156. @clleew
     References
     • pipenv
     
     • poetry
     
     • flake8
     
     • pylint
     
     • mypy
     
     • black
     
     • isort
     • invoke
     
     • pre-commit
     
     • commitizen-tools
     
     • safety
     
     • bandit
     
     • cookiecutter
     
     

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157. @clleew
     

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158. @clleew
     Let's chat on discord
     

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