auto-deprecator 2020.1.3

Python decorator and command to automate deprecating components

Auto deprecator

Python decorator and command to automate deprecating components

• Free software: MIT license

• Documentation: https://auto-deprecator.readthedocs.io.

How does it work?

We believe that deprecating a component in your library should work in the following ways

1. Alert the users the deprecation time

When the user calls the methods or initializes the objects which will be deprecated in the next version or on an expected date, the user should receive the warning of the future deprecation but get the return in success.

from auto_deprecator import deprecate

@deprecate(expiry='2.0.0')
def old_hello_world():
    return print("Hello world!")

>>> old_hello_world()
Hello world!
DeprecationWarning: The function "old_hello_world" will be deprecated on version 2.0.0

2. Test as if deprecated

Before the component is deprecated, unit / integration testing should be run to ensure the deprecation does not break the existing flow. Pass in the environment variables in the testing to simulate that the version is deployed.

(bash) hello-world-app
Hello world!
DeprecationWarning: The function "old_hello_world" will be deprecated in version 2.0.0

(bash) DEPRECATED_VERSION=2.0.0 hello-world-app
Traceback (most recent call last):
 ...
RuntimeError: The function "old_hello_world" is deprecated in version 2.0.0

3. Automatic deprecation before release

Deprecating the functions is no longer a manual work. Every time before release, run the command auto-deprecate to remove the functions deprecated in the coming version.

(bash) auto-deprecate hello_world.py --version 2.0.0
(bash) git diff

diff --git a/hello_world.py b/hello_world.py
index 201e546..ec41365 100644
--- a/hello_world.py
+++ b/hello_world.py
@@ -1,8 +1,2 @@
-from auto_deprecator import deprecate
-
 def hello_world():
     return print("Hello world!")
-
-@deprecate(expiry='2.0.0')
-def old_hello_world():
-    return print("Hello world!")

Installation

The library can be easily installed with pip

pip install auto-deprecator

Alternative Installation

If the auto-deprecator is included and the functions are well deprecated (following the whole cycle mentioned above), your software does not need auto-deprecator anymore. For developers who are not comfortable to include a library not always in use as a dependency, they can just clone the source code into your project instead.

For example, your Python project contains a module called “utils” to maintain all the utility functions.

.
├── setup.py
└── test_py_project
    ├── cli.py
    ├── __init__.py
    ├── test_py_project.py
    └── utils
        └── __init__.py

With the bash command “curl”,

curl -L https://github.com/gavincyi/auto-deprecator/tarball/master | tar xz -C <target_directory> --wildcards "*/auto_deprecator" --strip-components=1

the source code of auto-deprecator can be cloned into the target directory, i.e. “test_py_project/utils” in the example

touch test_py_project/utils/__init__.py
curl -L https://github.com/gavincyi/auto-deprecator/tarball/master | tar xz -C test_py_project/utils --wildcards "*/auto_deprecator" --strip-components=1

Features

Provide hints to users

Provide the parameter “relocate”, the warning / error message will inform the user about the relocated method.

@deprecate(expiry='2.1.0', current='2.0.0', relocate='new_compute_method')
def compute_method():
    return 'hello world'

>>> old_hello_world()
Hello world!
DeprecationWarning: The function "old_hello_world" will be deprecated on version 2.0.0..
                    Please use method / function "new_compute_method".

History

2010.1.0, 2010.1.1, 2010.1.2 (2020-01-21)

• Support alerting the users the deprecate version

• Support testing with environment variables

• Support automatically deprecate the expiry source code