autoload-module 1.3.1

Python Autoload Module

autoload_module

This library will give you comfortable Python metaprogramming.
The following is a plain example.

• Directory

project/
 ├ example.py
 └ validator/
   ├ validator_a.py
   ├ validator_b.py
   └ validator_c.py

• example.py

from autoload.module_loader import ModuleLoader

input = "foo bar baz"
loader = ModuleLoader()

# Automatically import modules and return class objects
validator_classes = loader.load_classes("validator")
try:
    # initialize and execute method
    [clazz().validate(input) for clazz in validator_classes]
except:
    print("input is invalid!!")

Install

pip install autoload-module

Usage

Constructor

ModuleLoader([base_path])

The ModuleLoader can be generated with no parameters. In that case, the instance has the absolute path where it was initialized.

• Directory

/usr/local/src/project/
  ├ example.py
  └ validator/
    ├ validator_a.py
    ├ validator_b.py
    └ validator_c.py

• example.py

from autoload.module_loader import ModuleLoader

# The instance has '/usr/local/src/project/'
loader = ModuleLoader()

# load modules in the directory; '/usr/local/src/project/validator/'
validator_classes = loader.load_classes("validator")

If you want to change the base path, you must generate the ModuleLoader with an absolute path parameter.

loader = ModuleLoader('/user/local/src/custom')

Methods

load_classes

load_classes(pkg_name, [excludes, recursive])

This method read the Python package and return the tuple of class objects.

• Directory

pkg/
 ├ example.py
 ├ __init__.py
 ├ config.yaml
 └ main/
     ├ validator_a.py
     ├ validator_b.py
     ├ validator_c.py
     └ sub/
        ├ validator_d.py
        └ validator_e.py

• validator_a.py

class ValidatorA:
    def validate(self):
        print("validateA!!")

• example.py

loader = ModuleLoader()

# Automatically read modules without '__init__.py', not py file, and this file.
# return the tuple of ValidateA, ValidatorB, and ValidatorC class objects
validator_classes = loader.load_classes("main")

# initialize and execute method
[clazz().validate() for clazz in validator_classes]
# -> validateA!!
# -> validateB!!
# -> validateC!!

You can also load only specific modules using excludes variable or load_config decorator as below.

# Pattern1: 'excludes'
# 'excludes' is a iterable object like tuple, list.
# You must specify module names in 'excludes'.
validator_classes = loader.load_classes("main", ["validator_a"])

[clazz().validate() for clazz in validator_classes]
# -> validateB!!
# -> validateC!!

# Pattern2: 'load_config'
from autoload.decorator import load_config

@load_config(load=False)
class ValidatorA:
  def validate(self):
    print("validateA!!")

validator_classes = loader.load_classes("main")

[clazz().validate() for clazz in validator_classes]
# -> validateB!!
# -> validateC!!

This function will check directory structure recursively if you specify recursive=True.

# 'recursive=False' is default.
# In this case, the loader will also check 'pkg/main/sub/'.
validator_classes = loader.load_classes("main", recursive=True)

[clazz().validate() for clazz in validator_classes]
# -> validateA!!
# -> validateB!!
# -> validateC!!
# -> validateD!!
# -> validateE!!

You can specify pkg_name as below.

loader.load_classes("main/validator_a.py")
loader.load_classes("main.validator_a")
loader.load_classes("./main/validator_a")
loader.load_classes(".main.validator_a")
loader.load_classes("main.sub.validator_d")
loader.load_classes("./main/sub/validator_d")
loader.load_classes("../otherpkg")
loader.load_classes("..otherpkg")

load_functions

load_functions(pkg_name, [excludes, recursive])

This method read the Python package and return the tuple of functions. The usage is the same as load_classes.

NOTE

• To search class or function, You must match the name of file, and the one of class or function. For example, if you named the file test_module.py, you must name the class TestModule or the function test_module. When you want to customize their name, use @load_config decorator.
  • validator_a.py

  from autoload.decorator import load_config
  
  @load_config()
  class CustomValidator:
      def validate(self):
          print("validateA!!")
  

• You can also control the order of loaded class objects using @load_config decorator.
  • validator_a.py

  from autoload.decorator import load_config
  
  # sort in ascending order
  @load_config(order=1)
  class ValidatorA:
      def validate(self):
          print("validateA!!")
  

load_class

load_class(file_name)

This method read the Python file and return the class object.

• Directory

project/
  ├ example.py
  └ validator.py

• validator.py

class Validator:
    def validate(self):
        print("validate!!")

• example.py

loader = ModuleLoader()
clazz = loader.load_class("validator")
clazz().validate()
# -> validate!!

How to specify file_name is the same as that of load_classes.

load_function

load_function(file_name)

This method read the Python file and return a function object. The usage is the same as load_class.

License

Released under the MIT license.