README.md

disl: super lightweight (only 35 lines) dependency injection (ioc) support for Python

A super simple and risk-free way to do dependency injection (ioc) in Python. The entire code base is only 35 lines (empty lines included). No need to use a complex 3rd-party framework or be concerned about the long-term viability of the library.

How to install

pip install disl

How to use

Suppose you have a module to read some products' info from a DB file, so the path to the DB file should be injected:

from disl import Inject

class ProductDb:
  def __init__(self):
    self.db_path=Inject()  # this variable will be set automatically
  
  def get_products(self):
    print(f"getting products from {self.db_path}")

In your main program, you link up the ProductDb object and the db_path:

from disl import Disl

di=Disl()  # this is the container
di.add_raw_bean("pdb", ProductDb()) # add the bean under the name "pdb"
di.add_raw_bean("db_path", "c:/Users/kent/test.db") # another bean
pdb=di.get_wired_bean("pdb")  # the db_path field in the pdb bean will be set
pdb.get_products()  # this pdb object is just the plain object you created

If the path to the DB is named "database_path" but your variable name is just "db_path", you can do it like this:

from disl import Inject

class ProductDb:
  def __init__(self):
    self.db_path=Inject("database_path") # specify the bean name
  
  def get_products(self):
    print(f"getting products from {self.db_path}")

from disl import Disl

di=Disl()
di.add_raw_bean("pdb", ProductDb())
di.add_raw_bean("database_path", "c:/Users/kent/test.db")
pdb=di.get_wired_bean("pdb")
pdb.get_products()