mirror of
https://github.com/ets-labs/python-dependency-injector.git
synced 2024-11-22 17:47:02 +03:00
72 lines
2.3 KiB
Python
72 lines
2.3 KiB
Python
"""`di.ExternalDependency` providers example."""
|
|
|
|
import sqlite3
|
|
import contextlib
|
|
import dependency_injector as di
|
|
|
|
|
|
class UserService(object):
|
|
"""Example class UserService.
|
|
|
|
UserService has dependency on DBAPI 2.0 database connection.
|
|
"""
|
|
|
|
def __init__(self, database):
|
|
"""Initializer.
|
|
|
|
Database dependency need to be injected via init arg.
|
|
"""
|
|
self.database = database
|
|
self.database.row_factory = sqlite3.dbapi2.Row
|
|
|
|
def init_database(self):
|
|
"""Initialize database, if it has not been initialized yet."""
|
|
with contextlib.closing(self.database.cursor()) as cursor:
|
|
cursor.execute("""
|
|
CREATE TABLE IF NOT EXISTS users(
|
|
id INTEGER PRIMARY KEY AUTOINCREMENT,
|
|
name VARCHAR(32)
|
|
)
|
|
""")
|
|
|
|
def create(self, name):
|
|
"""Create user with provided name and return his id."""
|
|
with contextlib.closing(self.database.cursor()) as cursor:
|
|
cursor.execute('INSERT INTO users(name) VALUES (?)', (name,))
|
|
return cursor.lastrowid
|
|
|
|
def get_by_id(self, id):
|
|
"""Return user info by user id."""
|
|
with contextlib.closing(self.database.cursor()) as cursor:
|
|
cursor.execute('SELECT id, name FROM users WHERE id=?', (id,))
|
|
return cursor.fetchone()
|
|
|
|
|
|
# Database and UserService providers:
|
|
database = di.ExternalDependency(instance_of=sqlite3.dbapi2.Connection)
|
|
users_service_factory = di.Factory(UserService,
|
|
database=database)
|
|
|
|
# Out of library's scope.
|
|
#
|
|
# Setting database provider:
|
|
database.provided_by(di.Singleton(sqlite3.dbapi2.Connection,
|
|
database=':memory:',
|
|
timeout=30,
|
|
detect_types=True,
|
|
isolation_level='EXCLUSIVE'))
|
|
|
|
# Creating UserService instance:
|
|
users_service = users_service_factory()
|
|
|
|
# Initializing UserService database:
|
|
users_service.init_database()
|
|
|
|
# Creating test user and retrieving full information about him:
|
|
test_user_id = users_service.create(name='test_user')
|
|
test_user = users_service.get_by_id(test_user_id)
|
|
|
|
# Making some asserts:
|
|
assert test_user['id'] == 1
|
|
assert test_user['name'] == 'test_user'
|